Photoelectrochemical(PEC)energy conversion has emerged as a promising and efficient approach to sustainable energy harvesting and storage.By utilizing semiconductor photoelectrodes,PEC devices can harness solar energy...Photoelectrochemical(PEC)energy conversion has emerged as a promising and efficient approach to sustainable energy harvesting and storage.By utilizing semiconductor photoelectrodes,PEC devices can harness solar energy and drive electrochemical reactions such as water splitting or carbon dioxide(CO_(2))reduction to generate clean fuels and value-added chemicals.However,PEC energy conversion faces several challenges such as high overpotential,sluggish reaction kinetics,charge carrier recombination,and stability issues,which limit its practical implementation.Recently,significant research has been conducted to improve the overall conversion efficiency of PEC devices.One particularly promising approach is the use of cocatalysts,which involves introducing specific cocatalysts onto the photoelectrode surface to promote charge separation,improve reaction kinetics,and reduce the overpotential,thereby enhancing the overall performance of PEC energy conversion.This review provides a comprehensive overview of the recent developments in the earth-abundant cocatalysts for PEC water splitting and CO_(2) reduction.The main earth-abundant catalysts for the PEC water splitting include transition-metal dichalcogenide(TMD)-based materials,metal phosphides/carbides,and metal oxides/hydroxides.Meanwhile,PEC-CO_(2)RR was divided into C_(1) and C_(2+)based on the final product since various products could be produced,focusing on diverse earth-abundant materials-based cocatalysts.In addition,we provide and highlight key advancements achieved in the very recent reports on novel PEC system design engineering with cocatalysts.Finally,the current problems associated with PEC systems are discussed along with a suggested direction to overcome these obstacles.展开更多
Efficient photocatalytic reduction of CO_(2) to high-calorific-value CH4,an ideal target product,is a blueprint for C_(1)industry relevance and carbon neutrality,but it also faces great challenges.Herein,we demonstrat...Efficient photocatalytic reduction of CO_(2) to high-calorific-value CH4,an ideal target product,is a blueprint for C_(1)industry relevance and carbon neutrality,but it also faces great challenges.Herein,we demonstrate unprecedented hybrid SiC photocatalysts modified by Fe-based cocatalyst,which are prepared via a facile impregnation-reduction method,featuring an optimized local electronic structure.It exhibits a superior photocatalytic carbon-based products yield of 30.0μmol g^(−1) h^(−1) and achieves a record CH_(4) selectivity of up to 94.3%,which highlights the effectiveness of electron-rich Fe cocatalyst for boosting photocatalytic performance and selectivity.Specifically,the synergistic effects of directional migration of photogenerated electrons and strongπ-back bonding on low-valence Fe effectively strengthen the adsorption and activation of reactants and intermediates in the CO_(2)→CH_(4) pathway.This study inspires an effective strategy for enhancing the multielectron reduction capacity of semiconductor photocatalysts with low-cost Fe instead of noble metals as cocatalysts.展开更多
2D-layered graphitic carbon nitride(g-C_(3)N_(4))is regarded as a great prospect as a photocatalyst for H_(2)generation.However,g-C_(3)N_(4)’s photocatalytic hydrogen evolution(HER)activity is significantly restricte...2D-layered graphitic carbon nitride(g-C_(3)N_(4))is regarded as a great prospect as a photocatalyst for H_(2)generation.However,g-C_(3)N_(4)’s photocatalytic hydrogen evolution(HER)activity is significantly restricted by the recombination of photocarriers.We find that cobalt sulfide(CoS_(2))as a cocatalyst can promote g-C_(3)N_(4)nanosheets(NSs)to realize very efficient photocatalytic H_(2)generation.The prepared CoS_(2)/g-C_(3)N_(4)hybrids display highly boosted photocatalytic H_(2)generation performance and outstanding cycle stability.The optimized 7%-CoS_(2)/g-C_(3)N_(4)hybrids show a much improved photocatalytic H_(2)generation rate of 36.2μmol-1h-1,which is about 180 times as much as bare g-C_(3)N_(4)(0.2μmol-1h-1).In addition,the apparent quantum efficiency(AQE)of all the samples was computed under light atλ=370 nm,in which the AQE of 7%-CoS_(2)/g-C_(3)N_(4)hybrids is up to 5.72%.The experimental data and the DFT calculation suggest that the CoS_(2)/g-C_(3)N_(4)hybrid’s excellent HER activity is attributable to the lower overpotential and the smaller Co-H bond activation energy for HER.Accordingly,the CoS_(2)cocatalyst loading effectively boosts the photocatalytic performance of g-C_(3)N_(4)for H_(2)evolution.The project promotes fast development of high-efficiency photocatalysts and low-cost for photocatalytic H_(2)generation.展开更多
Taking copper doped ZnS(ZnS:Cu)nanocrystals as the main body of photocatalyst,the influence of different base transition metal ions(M^(2+)=Ni^(2+),Co^(2+),Fe^(2+)and Cd^(2+))on photocatalytic CO_(2)reduction in inorga...Taking copper doped ZnS(ZnS:Cu)nanocrystals as the main body of photocatalyst,the influence of different base transition metal ions(M^(2+)=Ni^(2+),Co^(2+),Fe^(2+)and Cd^(2+))on photocatalytic CO_(2)reduction in inorganic reaction system is investigated.Confined single-atom Ni^(2+),Co^(2+),and Cd^(2+)sites were created via cation-exchange process and enhanced CO_(2)reduction,while Fe^(2+)suppressed the photocatalytic activity for both water and CO_(2)reduction.The modified ZnS:Cu photocatalysts(M/ZnS:Cu)demonstrated tunable product selectivity,with Ni^(2+)and Co^(2+)showing high selectivity for syngas production and Cd^(2+)displaying remarkable formate selectivity.DFT calculations indicated favorable H adsorption free energy on Ni^(2+)and Co^(2+)sites,promoting the hydrogen evolution reaction.The selectivity of CO_(2)reduction products was found to be sensitive to the initial intermediate adsorption states.*COOH formed on Ni^(2+)and Co^(2+)while*OCHO formed on Cd^(2+),favoring the production of CO and HCOOH as the main products,respectively.This work provides valuable insights for developing efficient solar-to-fuel platforms with controlled CO_(2)reduction selectivity.展开更多
Photocatalytic water splitting by semiconductors is a promising technology to produce clean H_(2) fuel,but the efficiency is restrained seriously by the high overpotential of the H_(2)-evolution reaction together with...Photocatalytic water splitting by semiconductors is a promising technology to produce clean H_(2) fuel,but the efficiency is restrained seriously by the high overpotential of the H_(2)-evolution reaction together with the high recombination rate of photoinduced charges.To enhance H_(2) production,it is highly desirable yet challenging to explore an efficient reductive cocatalyst and place it precisely on the right sites of the photocatalyst surface to work the proton reduction reaction exclusively.Herein,the metalloid NixP cocatalyst is exactly positioned on the Z-scheme Cd_(0.5)Zn_(0.5)S/NiTiO_(3)(CZS/NTO)heterostructure through a facile photodeposition strategy,which renders the cocatalyst form solely at the electron-collecting locations.It is revealed that the directional transfer of photoexcited electrons from Cd_(0.5)Zn_(0.5)S to Ni_(x)P suppresses the quenching of charge carriers.Under visible light,the CZS/NTO hybrid loaded with the Ni_(x)P cocatalyst exhibits an optimal H_(2) yield rate of 1103μmol h^(-1)(i.e.,27.57 mmol h^(-1)g^(-1)),which is about twofold of pristine CZS/NTO and comparable to the counterpart deposited with the Pt cocatalyst.Besides,the high apparent quantum yield(AQY)of 56%is reached at 400 nm.Further,the mechanisms of the cocatalyst formation and the H2 generation reaction are discussed in detail.展开更多
Photocatalytic solar energy conversion to hydrogen is sustainable and attractive for addressing the global energy and environmental issue. Herein, a novel photocatalytic system (NiS/Ni3S4 cocatalysts modified mesoporo...Photocatalytic solar energy conversion to hydrogen is sustainable and attractive for addressing the global energy and environmental issue. Herein, a novel photocatalytic system (NiS/Ni3S4 cocatalysts modified mesoporous TiO2) with superior photocatalytic hydrogen evolution capability through the synergistic impact of NiS/Ni3S4 (NiSx) cocatalyst and efficient hole scavenger has been demonstrated. The photocatalytic hydrogen evolution of TiO2-NiSx hybrids with the different content of NiSx and upon different organic hole scavengers was both investigated. The hybrid of TiO2 decorated with 3%(mole ratio of Ni^2+) NiSx cocatalyst in methanol solution showed the optimal photocatalytic hydrogen evolution rate of 981.59 μmol h^-1 g^-1 which was about 20 times higher than that of bare mesoporous TiO2. Our results suggested that the boosted hydrogen production performance is attributed to both the improved photoinduced electrons migration between NiS and Ni3S4 in cocatalyst and the high hole captured efficiency by hole scavengers of methanol.展开更多
Cocatalysts play important roles in improving the activity and stability of most photocatalysts.It is of great significance to develop economical,efficient and stable cocatalysts.Herein,using Na2CoFe(CN)6 complex as p...Cocatalysts play important roles in improving the activity and stability of most photocatalysts.It is of great significance to develop economical,efficient and stable cocatalysts.Herein,using Na2CoFe(CN)6 complex as precursor,a novel noble-metal-free FeCo@NGC cocatalyst(nano-FeCo alloy@N-doped graphitized carbon) is fabricated by a simple pyrolysis method.Coupling with g-C3 N4, the optimal FeCo@NGC/g-C3N4 receives a boosted visible light driven photocatalytic H2 evolution rate of 42.2 μmol h-1, which is even higher than that of 1.0 wt% Pt modified g-C3N4 photocatalyst.Based on the results of density functional theory(DFT) calculations and practical experiment measurements,such outstanding photocatalytic performance of FeCo@NGC/g-C3N4 is mainly attributed to two aspects.One is the accelerated charge transfer behavior,induced by a photogene rated electrons secondary transfer performance on the surface of FeCo alloy nanoparticles.The other is related to the adjustment of H adsorption energy(approaching the standard hydrogen electrode potential) by the presence of external NGC thin layer.Both factors play key roles in the H2 evolution reaction.Such outstanding performance highlights an enormous potential of developing noble-metal-free bimetallic nano-alloy as inexpensive and efficient cocatalysts for solar applications.展开更多
Conversion of carbon dioxide(CO_(2))into valuable chemicals and renewable fuels via photocatalysis represents an eco-friendly route to achieve the goal of carbon neutralization.Although various types of semiconductor ...Conversion of carbon dioxide(CO_(2))into valuable chemicals and renewable fuels via photocatalysis represents an eco-friendly route to achieve the goal of carbon neutralization.Although various types of semiconductor materials have been intensively explored,some severe issues,such as rapid charge recombination and sluggish redox reaction kinetics,remain.In this regard,cocatalyst modifi cation by trapping charges and boosting surface reactions is one of the most effi cient strategies to improve the effi ciency of semiconductor photocatalysts.This review focuses on recent advances in CO_(2)photoreduction over costeff ective and earth-abundant cobalt(Co)-based cocatalysts,which are competitive candidates of noble metals for practical applications.First,the functions of Co-based cocatalysts for promoting photocatalytic CO_(2)reduction are briefl y discussed.Then,diff erent kinds of Co-based cocatalysts,including cobalt oxides and hydroxides,cobalt nitrides and phosphides,cobalt sulfi des and selenides,Co single-atom,and Co-based metal–organic frameworks(MOFs),are summarized.The underlying mechanisms of these Co-based cocatalysts for facilitating CO_(2)adsorption–activation,boosting charge separation,and modulating intermediate formation are discussed in detail based on experimental characterizations and density functional theory calculations.In addition,the suppression of the competing hydrogen evolution reaction using Co-based cocatalysts to promote the product selectivity of CO_(2)reduction is highlighted in some selected examples.Finally,the challenges and future perspectives on constructing more effi cient Co-based cocatalysts for practical applications are proposed.展开更多
Photodeposition is widely adopted for implanting metal/metal oxide cocatalysts on semiconductors.However,it is prerequisite that the photon energy should be sufficient to excite the host semiconductor.Here,we report a...Photodeposition is widely adopted for implanting metal/metal oxide cocatalysts on semiconductors.However,it is prerequisite that the photon energy should be sufficient to excite the host semiconductor.Here,we report a lower-energy irradiation powered deposition strategy for implanting CrO_(x) cocatalyst on TiO_(2).Excitingly,CrO_(x)-400 implanted under visible-light irradiation significantly promotes the CH4 evolution rate on TiO_(2)to 8.4μmolg·^(-1)h^(-1) with selectivity of98%from photocatalytic CO_(2)reduction,which is 15 times of that on CrO_(x)-200 implanted under UV-visible-light irradiation.Moreover,CrO_(x)-400 is identified to be composed of higher valence Cr species compared to CrO_(x)-200.This valence states regulation of Cr species is indicated to provide more active sites for CO_(2) adsorption/activation and to modulate the reaction mechanism from single Cr site to Cr-Cr dual sites,thus endowing the superior CH_(4)production.This work demonstrates an alternative strategy for constructing efficient metal oxides cocatalysts on wide bandgap semiconductor.展开更多
β-Ge3N4 loaded with nanoparticulate RuO2 as a cocatalyst is the first successful non-oxide photocatalyst for overall water splitting.To get an insight into the working mechanism of this particular photocatalytic syst...β-Ge3N4 loaded with nanoparticulate RuO2 as a cocatalyst is the first successful non-oxide photocatalyst for overall water splitting.To get an insight into the working mechanism of this particular photocatalytic system,we have calculated geometrical structures of low-index surfaces forβ-Ge3N4.Analysis of surface energies indicates that the most preferentially exposed surface is(100).The band gap of surface is narrower than that of bulk due to the dangling bonds.Dissociative water adsorption on(100)surface is thermodynamically favorable.The adsorption behavior of(RuO2)n(n=2,3,and 4)clusters on theβ-Ge3N4(100)surface has been explored.It is found that all the clusters bind to(100)surface strongly by forming interfacial bonds so that the adsorptions are exothermic processes.The calculation on density of states forβ-Ge3N4(100)surface loaded with(RuO2)nclusters reveals that photo-induced electrons tend to accumulate on(RuO2)nclusters and holes tend to stay inβ-Ge3N4.Based on the theoretical indication of Type-II staggered band alignment,we have proposed that in photocatalytic water splitting reaction,oxygen evolution reaction is inclined to occur on the surface ofβ-Ge3N4 while hydrogen evolution reaction is apt to occur on(RuO2)nclusters.In a word,loading RuO2 nanoparticles as a reduction cocatalyst benefits the charge separation inβ-Ge3N4.Furthermore,attaching(RuO2)nclusters ontoβ-Ge3N4(100)surface results in the redshift of absorption edge and the increase of absorption intensity.Our calculations have reasonably explained the experimental observation on the decomposition of water into H2 and O2 after loading RuO2 cocatalyst inβ-Ge3N4 photocatalyst.展开更多
Aluminoxanes containing both ethyl and iso-butyl groups were synthesized by thehydrolysis of Al(C2H3)3 (TEA)/Al(i-C4H9)3 (TIBA) mixtures. The aluminoxane made from theTEA/TIBA mixture of molar ratio 7:3 showed cocatal...Aluminoxanes containing both ethyl and iso-butyl groups were synthesized by thehydrolysis of Al(C2H3)3 (TEA)/Al(i-C4H9)3 (TIBA) mixtures. The aluminoxane made from theTEA/TIBA mixture of molar ratio 7:3 showed cocatalyst activity of about five times as those ofethylaluminoxane or isobutylaluminoxane for ethylene polymerization catalyzed by Cp2ZrCl2. Thealuminoxane was characterized and the possible reasons for its high activity were discussed.展开更多
Based on the deficiency of catalytic elements in methane sensors such as sintering,activity decrease and surface area reduction at high temperature, three differentnano vectors Ce-Zr-Al_2O_3, Ce-Al_2O_3, and Zr-Al_2O_...Based on the deficiency of catalytic elements in methane sensors such as sintering,activity decrease and surface area reduction at high temperature, three differentnano vectors Ce-Zr-Al_2O_3, Ce-Al_2O_3, and Zr-Al_2O_3 were prepared via sol-gel technique inthe experiment.BET surface area, catalytic activity and thermal stability were tested andcompared.It is found from the experiment that the Ce-doped Al_2O_3 vector possesseshigher catalytic activity than pure Al_2O_3 vector.Zr-doped Al_2O_3 vector can enhance thethermal stability of methane sensors.Ce-Zr-Al solid solution can be obtained by the presenceof Ce and Zr doped with Al_2O_3.The reaction activity and thermal stability of catalyticsensors were improved because of the unique synergy effect from Ce-Zr-O.Among themixed cocatalysts, Ce-Zr-O was reported to be an excellent cocatalyst material.The performanceof methane sensors can be improved significantly via the modification ofCe-Zr-Al_2O_3 vector.展开更多
Recently,Yu and co-workers deeply explore the potential impact of free electron transfer between co-catalysts and photocatalyst carriers on H_(2)evolution efficiency of active sites over MoS_(2+x).They pro-pose an ele...Recently,Yu and co-workers deeply explore the potential impact of free electron transfer between co-catalysts and photocatalyst carriers on H_(2)evolution efficiency of active sites over MoS_(2+x).They pro-pose an electron-reversal tactics to evade the unexpected electron transfer and synchronously regulate the above transfer in a beneficial orientation for weakening hydrogen adsorption on S sites.Herein,this highlight not only discusses and summarizes the essences of electron reversal and the optimized H ad-sorption/desorption mechanism,but also emphasizes the significance of femtosecond transient absorp-tion spectroscopy(fs-TAS)and in-situ irradiated X-ray photoelectron spectroscopy(ISI-XPS)for revealing charge transfer dynamics and processes.We anticipate that this highlight can disseminate a new per-spective on the roles of photocatalyst carriers in improving cocatalytic H_(2)-production kinetics.展开更多
Selective loading of spatially separated redox cocatalysts on direct Z-scheme heterojunctions holds great promise for advancing the efficiency of artificial photosynthesis,which however is limited to the photodepositi...Selective loading of spatially separated redox cocatalysts on direct Z-scheme heterojunctions holds great promise for advancing the efficiency of artificial photosynthesis,which however is limited to the photodeposition of noble metal cocatalysts and the fabrication of hollow double-shelled semiconductor heterojunctions.Moreover,the co-exposure of discrete cocatalyst and semiconductor increases the product diversity when both the exposed sites of which participate in CO_(2)photoreduction.Herein,we present a facile and versatile protocol to overcome these limitations via surface coating of Z-scheme heterojunctions with bifunctional noble-metal-free cocatalysts.With Cu_(2)O/Fe_(2)O_(3)(CF)as a model heterojunction and layered Ni(OH)_(2)as a model cocatalyst,it is found that Ni(OH)_(2)lying on the surfaces of Cu_(2)O and Fe_(2)O_(3)separately co-catalyzes the CO_(2)reduction and H_(2)O oxidation.Thorough experimental and theoretical investigation reveals that the Ni(OH)_(2)outer layer:(i)mitigates the charge recombination in CF and balances their transfer and consumption;(ii)reduces the rate-determining barriers for CO_(2)-to-CO and H_(2)O-to-O_(2)conversion,(iii)suppresses the side proton reduction occurring on CF,and(iv)protects the CF from component detachment.As expected,the redox reactions stoichiometrically proceed,and significantly enhanced photocatalytic activity,selectivity,and stability in CO generation are achieved by the stacked Cu_(2)O/Fe_(2)O_(3)@Ni(OH)_(2)in contrast to CF.This study demonstrates the significance of the synergy between bifunctional cocatalysts and Z-scheme heterojunctions for improving the efficacy of overall redox reactions,opening a fresh avenue for the rational design of artificial photosynthetic systems.展开更多
The visible-light-driven hydrogen evolution is extremely important,but the poor charge transfer capa-bility,a sluggish evolution rate of hydrogen,and severe photo-corrosion make photocatalytic hydrogen evolution impra...The visible-light-driven hydrogen evolution is extremely important,but the poor charge transfer capa-bility,a sluggish evolution rate of hydrogen,and severe photo-corrosion make photocatalytic hydrogen evolution impractical.In this study,we present 1D/2D ReS_(2)-CdS hybrid nanorods for photocatalytic hy-drogen evolution,comprised of a ReS_(2)nanosheet layer grown on CdS nanorods.We found that precise control of the contents of the ReS_(2)nanosheet layer allows for manipulating the electronic structure of Re in the ReS_(2)-CdS hybrid nanorods.The ReS_(2)-CdS hybrid nanorods with optimal ReS_(2)nanosheet layer content dramatically improve photocatalytic hydrogen evolution activity.Notably,photocatalytic hydro-gen evolution activity(64.93 mmol g^(−1)h^(−1))of ReS_(2)-CdS hybrid nanorods with ReS_(2)nanosheet layers(Re/Cd atomic ratio of 0.051)is approximately 136 times higher than that of pure CdS nanorods under visible light irradiation.Furthermore,intimated coupling of the ReS_(2)nanosheet layer with CdS nanorods reduced the surface trap-site of the CdS nanorods,resulting in enhanced photocatalytic stability.The de-tailed optical and electrical investigations demonstrate that the optimal ReS_(2)nanosheet layer contents in the ReS_(2)-CdS hybrid nanorods can provide improved charge transfer capability,catalytic activity,and light absorption efficiency.This study sheds light on the development of photocatalysts for highly efficient photocatalytic hydrogen evolution.展开更多
Metal halide perovskite(MHP)has become one of the most promising materials for photocatalytic CO_(2)reduction owing to the wide light absorption range,negative conduction band position and high reduction ability.Howev...Metal halide perovskite(MHP)has become one of the most promising materials for photocatalytic CO_(2)reduction owing to the wide light absorption range,negative conduction band position and high reduction ability.However,photoreduction of CO_(2)by MHP remains a challenge because of the slow charge separation and transfer.Herein,a cobalt single-atom modified nitrogen-doped graphene(Co-NG)cocatalyst is prepared for enhanced photocatalytic CO_(2)reduction of bismuth-based MHP Cs_(3)Bi_(2)Br_(9).The optimal Cs_(3)Bi_(2)Br_(9)/Co-NG composite exhibits the CO production rate of 123.16μmol g-1 h-1,which is 17.3 times higher than that of Cs_(3)Bi_(2)Br_(9).Moreover,the Cs_(3)Bi_(2)Br_(9)/Co-NG composite photocatalyst exhibits nearly 100%CO selectivity as well as impressive long-term stability.Charge carrier dynamic characterizations such as Kelvin probe force microscopy(KPFM),single-particle PL microscope and transient absorption(TA)spectroscopy demonstrate the vital role of Co-NG cocatalyst in accelerating the transfer and separation of photogenerated charges and improving photocatalytic performance.The reaction mechanism has been demonstrated by in situ diffuse reflectance infrared Fourier-transform spectroscopy measurement.In addition,in situ X-ray photoelectron spectroscopy test and theoretical calculation reveal the reaction reactive sites and reaction energy barriers,demonstrating that the introduction of Co-NG promotes the formation of~(*)COOH intermediate,providing sufficient evidence for the highly selective generation of CO.This work provides an effective single-atom-based cocatalyst modification strategy for photocatalytic CO_(2)reduction and is expected to shed light on other photocatalytic applications.展开更多
Molybdenum disulfide(Mo S_(2))has attracted great attention in hydrogen peroxide(H_(2)O_(2))activation as a Fenton-like catalyst and cocatalyst,but the distinct mechanism of generating^(·)OH remains unclear.In th...Molybdenum disulfide(Mo S_(2))has attracted great attention in hydrogen peroxide(H_(2)O_(2))activation as a Fenton-like catalyst and cocatalyst,but the distinct mechanism of generating^(·)OH remains unclear.In this paper,the metallic 1T phase and semiconducting 2H phase of Mo S_(2)nanosheets were prepared and applied in MoS_(2)/H_(2)O_(2)and MoS_(2)/Fe^(2+)/H_(2)O_(2)systems with and without light irradiation.Compared with2H-MoS_(2),1T-MoS_(2)exhibited superior removal rates in degrading organic pollutants in the two systems under light irradiation.However,the phase had little effect on activating H_(2)O_(2)in the Mo S_(2)/H_(2)O_(2)system under dark conditions.This is because it was difficult for the surface^(·)OH_(ads)generated in the Mo S_(2)/H_(2)O_(2)system to diffuse into solution,while the^(·)OH_(free)radicals were mainly responsible for degrading organic pollutants.When introducing light irradiation,external energy may accelerate the desorption of^(·)OH_(ads)into^(·)OH_(free.)Interestingly,the conversion between Mo^(4+)and Mo^(5+)triggered the decomposition of H_(2)O_(2)in the Fenton-like reaction,while the cycle of Mo^(4+)/Mo^(6+)promoted the regeneration of Fe^(3+)when employing 1T-MoS_(2)as a cocatalyst.Meanwhile,the 1T-MoS_(2)catalysts exhibited excellent stability and ability to degrade various organics in the two systems.This work offers deeper insight into the Mo S_(2)-based Fenton-like and cocatalytic mechanisms.展开更多
Photocatalysis, which performed under mild conditions by utilizing solar energy, has become a desirable technology to convert methane into highly valuable chemicals, such as methanol, ethane, and other hydrocarbons. H...Photocatalysis, which performed under mild conditions by utilizing solar energy, has become a desirable technology to convert methane into highly valuable chemicals, such as methanol, ethane, and other hydrocarbons. However, pristine photocatalysts still suffer from the low utilization efficiency of solar light and the high recombination rate of photogenerated charge carriers, which exhibit the low activity and selectivity for photocatalytic methane conversion. Loading cocatalysts on photocatalysts is an attractive strategy to manipulate the products' yield and selectivity of photocatalytic methane conversion due to the enhanced charge carrier separation efficiency, extended light absorption and promoted reactant adsorption/desorption kinetics. This review discusses the recent achievements of the cocatalysts for photocatalytic methane conversion reactions. Moreover, the challenges and perspectives for the development of efficient cocatalysts are presented. This review provides considerable guidelines for the design and construction of efficient cocatalysts for photocatalytic methane conversion reactions.展开更多
Aiming to develop a photocatalyst that can simultaneously produce valuable chemicals and clean H_(2) fuel for promoting the utilization efficiency of solar energy,herein,a sea-urchin-like CoP@Ni_(2)P binary nanojuncti...Aiming to develop a photocatalyst that can simultaneously produce valuable chemicals and clean H_(2) fuel for promoting the utilization efficiency of solar energy,herein,a sea-urchin-like CoP@Ni_(2)P binary nanojunction was employed as an efficient photothermal cocatalyst to couple with zero-dimensional CdZnS(CZS)solid solution for achieving superior coordinative redox reaction.The CoP@Ni_(2)P/CZS hybrid displayed a high solar-driven H_(2) generation rate of 40.92 mmol g^(–1) h^(–1) coupling with a benzaldehyde formation rate of 20.33 mmol g^(–1) h^(–1),which was 16.4 and 8.0 times higher than that of bare CZS.Furthermore,the CoP@Ni_(2)P/CZS hybrid also achieved a high photothermal H_(2) production under a broad light range from 420 to 720 nm,and the H_(2) production reached 44.48μmol g^(–1) h^(–1) under the 720 nm light illumination.The enhanced catalytic performance can be ascribed to that the CoP@Ni_(2)P nanojunction with photothermal effect can speed up the separation and transport of carriers,offer more catalytic active sites,and induce an increase in temperature to optimize reaction kinetics.This study may open a facile route to design novel binary metal phosphides with dual functions in photocatalysis for the full exploitation of solar energy.展开更多
Traditional bulk MoS_(2) as an effective H_(2)-evolution cocatalyst is mainly subjected to the weak hydrogen-adsorption ability of highporpotion saturated S,resulting in a slow interfacial H_(2)-evolution reaction.In ...Traditional bulk MoS_(2) as an effective H_(2)-evolution cocatalyst is mainly subjected to the weak hydrogen-adsorption ability of highporpotion saturated S,resulting in a slow interfacial H_(2)-evolution reaction.In this paper,an efficient strategy for enhancing hydrogen adsorption of saturated S by manipulating electron density through O atoms is proposed to boost photocatalytic performance of CdS.Simultaneously,amorphization of MoS_(2) can further increase the unsaturated active S sites.Herein,oxygencontained amorphous MoS_(x)(a-MoOS_(x))nanoparticles(10-30 nm)were tightly loaded on the CdS surface through a mild photoinduced deposition method by using(NH_(4))_(2)[MoO(S_(4))_(2)]solution as the precursor at room temperature.The photocatalytic H_(2)-evolution result showed that the a-MoOS_(x)/CdS performed the superior H_(2)-production activity(382μmol·h^(-1),apparent quantum efficiencies(AQE)=11.83%)with a lot of visual H_(2)bubbles,which was 54.6,2.5,and 5.1 times as high as that of CdS,MoS_(x)/CdS,and annealed a-MoOS_(x)/CdS,respectively.Characterizations and density functional theory(DFT)calculations revealed the mechanism of improved H_(2)-evolution activity is that the O heteroatom in amorphous MoOS_(x) can enhance the atomic H-adsorption ability by manipulating the electron density to form electron-deficient S^((2-δ)-)sites.This study provides a new idea to improve the efficiency and number of H_(2)-evolution active sites for developing efficient cocatalysts in the field of photocatalytic hydrogen evolution.展开更多
基金supported by the National Research Foundation of Korea (NRF)funded by the Korean government (2021R1A4A3027878,2022M3H4A1A01012712)。
文摘Photoelectrochemical(PEC)energy conversion has emerged as a promising and efficient approach to sustainable energy harvesting and storage.By utilizing semiconductor photoelectrodes,PEC devices can harness solar energy and drive electrochemical reactions such as water splitting or carbon dioxide(CO_(2))reduction to generate clean fuels and value-added chemicals.However,PEC energy conversion faces several challenges such as high overpotential,sluggish reaction kinetics,charge carrier recombination,and stability issues,which limit its practical implementation.Recently,significant research has been conducted to improve the overall conversion efficiency of PEC devices.One particularly promising approach is the use of cocatalysts,which involves introducing specific cocatalysts onto the photoelectrode surface to promote charge separation,improve reaction kinetics,and reduce the overpotential,thereby enhancing the overall performance of PEC energy conversion.This review provides a comprehensive overview of the recent developments in the earth-abundant cocatalysts for PEC water splitting and CO_(2) reduction.The main earth-abundant catalysts for the PEC water splitting include transition-metal dichalcogenide(TMD)-based materials,metal phosphides/carbides,and metal oxides/hydroxides.Meanwhile,PEC-CO_(2)RR was divided into C_(1) and C_(2+)based on the final product since various products could be produced,focusing on diverse earth-abundant materials-based cocatalysts.In addition,we provide and highlight key advancements achieved in the very recent reports on novel PEC system design engineering with cocatalysts.Finally,the current problems associated with PEC systems are discussed along with a suggested direction to overcome these obstacles.
基金supported by the National Natural Science Foundation of China(Grant No.22072022)the Natural Science Foundation of Fujian Province(2021L3003)the Science Foundation of Shandong Province(ZR2019BB065).
文摘Efficient photocatalytic reduction of CO_(2) to high-calorific-value CH4,an ideal target product,is a blueprint for C_(1)industry relevance and carbon neutrality,but it also faces great challenges.Herein,we demonstrate unprecedented hybrid SiC photocatalysts modified by Fe-based cocatalyst,which are prepared via a facile impregnation-reduction method,featuring an optimized local electronic structure.It exhibits a superior photocatalytic carbon-based products yield of 30.0μmol g^(−1) h^(−1) and achieves a record CH_(4) selectivity of up to 94.3%,which highlights the effectiveness of electron-rich Fe cocatalyst for boosting photocatalytic performance and selectivity.Specifically,the synergistic effects of directional migration of photogenerated electrons and strongπ-back bonding on low-valence Fe effectively strengthen the adsorption and activation of reactants and intermediates in the CO_(2)→CH_(4) pathway.This study inspires an effective strategy for enhancing the multielectron reduction capacity of semiconductor photocatalysts with low-cost Fe instead of noble metals as cocatalysts.
基金funding from the National Natural Science Foundation of China(No.51872173 and 51772176)Taishan Scholar Foundation of Shandong Province(No.tsqn201812068 and tspd20161006)+2 种基金Youth Innovation Technology Project of Higher School in Shandong Province(No.2019KJA013)Science and Technology Special Project of Qingdao City(No.20-3-4-3-nsh)the Opening Fund of State Key Laboratory of Heavy Oil Processing(No.SKLOP202002006)。
文摘2D-layered graphitic carbon nitride(g-C_(3)N_(4))is regarded as a great prospect as a photocatalyst for H_(2)generation.However,g-C_(3)N_(4)’s photocatalytic hydrogen evolution(HER)activity is significantly restricted by the recombination of photocarriers.We find that cobalt sulfide(CoS_(2))as a cocatalyst can promote g-C_(3)N_(4)nanosheets(NSs)to realize very efficient photocatalytic H_(2)generation.The prepared CoS_(2)/g-C_(3)N_(4)hybrids display highly boosted photocatalytic H_(2)generation performance and outstanding cycle stability.The optimized 7%-CoS_(2)/g-C_(3)N_(4)hybrids show a much improved photocatalytic H_(2)generation rate of 36.2μmol-1h-1,which is about 180 times as much as bare g-C_(3)N_(4)(0.2μmol-1h-1).In addition,the apparent quantum efficiency(AQE)of all the samples was computed under light atλ=370 nm,in which the AQE of 7%-CoS_(2)/g-C_(3)N_(4)hybrids is up to 5.72%.The experimental data and the DFT calculation suggest that the CoS_(2)/g-C_(3)N_(4)hybrid’s excellent HER activity is attributable to the lower overpotential and the smaller Co-H bond activation energy for HER.Accordingly,the CoS_(2)cocatalyst loading effectively boosts the photocatalytic performance of g-C_(3)N_(4)for H_(2)evolution.The project promotes fast development of high-efficiency photocatalysts and low-cost for photocatalytic H_(2)generation.
基金financial support from the Tangshan Talent Funding Project(A202202007)the National Natural Science Foundation of China(21703065)+3 种基金the Natural Science Foundation of Hebei Province(B2018209267)the World Premier International Research Center Initiative(WPI Initiative)on Materials Nanoarchitectonics(MANA),the MEXT(Japan)the Photoexcitonix Project in Hokkaido Universitythe JSPS KAKENHI(Grant Number JP18H02065)。
文摘Taking copper doped ZnS(ZnS:Cu)nanocrystals as the main body of photocatalyst,the influence of different base transition metal ions(M^(2+)=Ni^(2+),Co^(2+),Fe^(2+)and Cd^(2+))on photocatalytic CO_(2)reduction in inorganic reaction system is investigated.Confined single-atom Ni^(2+),Co^(2+),and Cd^(2+)sites were created via cation-exchange process and enhanced CO_(2)reduction,while Fe^(2+)suppressed the photocatalytic activity for both water and CO_(2)reduction.The modified ZnS:Cu photocatalysts(M/ZnS:Cu)demonstrated tunable product selectivity,with Ni^(2+)and Co^(2+)showing high selectivity for syngas production and Cd^(2+)displaying remarkable formate selectivity.DFT calculations indicated favorable H adsorption free energy on Ni^(2+)and Co^(2+)sites,promoting the hydrogen evolution reaction.The selectivity of CO_(2)reduction products was found to be sensitive to the initial intermediate adsorption states.*COOH formed on Ni^(2+)and Co^(2+)while*OCHO formed on Cd^(2+),favoring the production of CO and HCOOH as the main products,respectively.This work provides valuable insights for developing efficient solar-to-fuel platforms with controlled CO_(2)reduction selectivity.
基金supported by the National Key R&D Program of China(2021YFA1502100 and 2022YFE0114800)the National Natural Science Foundation of China(22372035,22302039 and 22311540011).
文摘Photocatalytic water splitting by semiconductors is a promising technology to produce clean H_(2) fuel,but the efficiency is restrained seriously by the high overpotential of the H_(2)-evolution reaction together with the high recombination rate of photoinduced charges.To enhance H_(2) production,it is highly desirable yet challenging to explore an efficient reductive cocatalyst and place it precisely on the right sites of the photocatalyst surface to work the proton reduction reaction exclusively.Herein,the metalloid NixP cocatalyst is exactly positioned on the Z-scheme Cd_(0.5)Zn_(0.5)S/NiTiO_(3)(CZS/NTO)heterostructure through a facile photodeposition strategy,which renders the cocatalyst form solely at the electron-collecting locations.It is revealed that the directional transfer of photoexcited electrons from Cd_(0.5)Zn_(0.5)S to Ni_(x)P suppresses the quenching of charge carriers.Under visible light,the CZS/NTO hybrid loaded with the Ni_(x)P cocatalyst exhibits an optimal H_(2) yield rate of 1103μmol h^(-1)(i.e.,27.57 mmol h^(-1)g^(-1)),which is about twofold of pristine CZS/NTO and comparable to the counterpart deposited with the Pt cocatalyst.Besides,the high apparent quantum yield(AQY)of 56%is reached at 400 nm.Further,the mechanisms of the cocatalyst formation and the H2 generation reaction are discussed in detail.
基金the National Natural Science Foundation of China(21501137)the Hubei Natural Science Foundation for financial support(2018CFB680)Support from the Australian Research Council(ARC)through ARC Discovery projects(DP130102699,DP 130102274,DP160102627)
文摘Photocatalytic solar energy conversion to hydrogen is sustainable and attractive for addressing the global energy and environmental issue. Herein, a novel photocatalytic system (NiS/Ni3S4 cocatalysts modified mesoporous TiO2) with superior photocatalytic hydrogen evolution capability through the synergistic impact of NiS/Ni3S4 (NiSx) cocatalyst and efficient hole scavenger has been demonstrated. The photocatalytic hydrogen evolution of TiO2-NiSx hybrids with the different content of NiSx and upon different organic hole scavengers was both investigated. The hybrid of TiO2 decorated with 3%(mole ratio of Ni^2+) NiSx cocatalyst in methanol solution showed the optimal photocatalytic hydrogen evolution rate of 981.59 μmol h^-1 g^-1 which was about 20 times higher than that of bare mesoporous TiO2. Our results suggested that the boosted hydrogen production performance is attributed to both the improved photoinduced electrons migration between NiS and Ni3S4 in cocatalyst and the high hole captured efficiency by hole scavengers of methanol.
基金supported by the National Natural Science Foundation of China (21972048, 21802046)the Natural Science Foundation of Guangdong Province (Nos. 2019A1515011138, 2017A030313090, 2017A030310086, 2018A0303130018)。
文摘Cocatalysts play important roles in improving the activity and stability of most photocatalysts.It is of great significance to develop economical,efficient and stable cocatalysts.Herein,using Na2CoFe(CN)6 complex as precursor,a novel noble-metal-free FeCo@NGC cocatalyst(nano-FeCo alloy@N-doped graphitized carbon) is fabricated by a simple pyrolysis method.Coupling with g-C3 N4, the optimal FeCo@NGC/g-C3N4 receives a boosted visible light driven photocatalytic H2 evolution rate of 42.2 μmol h-1, which is even higher than that of 1.0 wt% Pt modified g-C3N4 photocatalyst.Based on the results of density functional theory(DFT) calculations and practical experiment measurements,such outstanding photocatalytic performance of FeCo@NGC/g-C3N4 is mainly attributed to two aspects.One is the accelerated charge transfer behavior,induced by a photogene rated electrons secondary transfer performance on the surface of FeCo alloy nanoparticles.The other is related to the adjustment of H adsorption energy(approaching the standard hydrogen electrode potential) by the presence of external NGC thin layer.Both factors play key roles in the H2 evolution reaction.Such outstanding performance highlights an enormous potential of developing noble-metal-free bimetallic nano-alloy as inexpensive and efficient cocatalysts for solar applications.
基金supported by the National Natural Science Foundation of China(Nos.21905049,22178057)the Natural Science Foundation of Fujian Province(Nos.2020J01201,2021J01197)+1 种基金the Research Foundation of the Academy of Carbon Neutrality of Fujian Normal University(TZH2022-07)the Award Program for Minjiang Scholar Professorship。
文摘Conversion of carbon dioxide(CO_(2))into valuable chemicals and renewable fuels via photocatalysis represents an eco-friendly route to achieve the goal of carbon neutralization.Although various types of semiconductor materials have been intensively explored,some severe issues,such as rapid charge recombination and sluggish redox reaction kinetics,remain.In this regard,cocatalyst modifi cation by trapping charges and boosting surface reactions is one of the most effi cient strategies to improve the effi ciency of semiconductor photocatalysts.This review focuses on recent advances in CO_(2)photoreduction over costeff ective and earth-abundant cobalt(Co)-based cocatalysts,which are competitive candidates of noble metals for practical applications.First,the functions of Co-based cocatalysts for promoting photocatalytic CO_(2)reduction are briefl y discussed.Then,diff erent kinds of Co-based cocatalysts,including cobalt oxides and hydroxides,cobalt nitrides and phosphides,cobalt sulfi des and selenides,Co single-atom,and Co-based metal–organic frameworks(MOFs),are summarized.The underlying mechanisms of these Co-based cocatalysts for facilitating CO_(2)adsorption–activation,boosting charge separation,and modulating intermediate formation are discussed in detail based on experimental characterizations and density functional theory calculations.In addition,the suppression of the competing hydrogen evolution reaction using Co-based cocatalysts to promote the product selectivity of CO_(2)reduction is highlighted in some selected examples.Finally,the challenges and future perspectives on constructing more effi cient Co-based cocatalysts for practical applications are proposed.
基金supported by the National Key Research and Development Program of China(2016YFB0700205,2017YFA0403402,2019YFA0405602,2017YFA0204904)the National Natural Science Foundation of China(52002367,21673214,U1732272,U1632273,U1832165)+1 种基金the foundation from Users with Excellence Program of Hefei Science Center CAS(2020HSC-UE001)the Fundamental Research Funds for the Central Universities(WK2310000093)。
文摘Photodeposition is widely adopted for implanting metal/metal oxide cocatalysts on semiconductors.However,it is prerequisite that the photon energy should be sufficient to excite the host semiconductor.Here,we report a lower-energy irradiation powered deposition strategy for implanting CrO_(x) cocatalyst on TiO_(2).Excitingly,CrO_(x)-400 implanted under visible-light irradiation significantly promotes the CH4 evolution rate on TiO_(2)to 8.4μmolg·^(-1)h^(-1) with selectivity of98%from photocatalytic CO_(2)reduction,which is 15 times of that on CrO_(x)-200 implanted under UV-visible-light irradiation.Moreover,CrO_(x)-400 is identified to be composed of higher valence Cr species compared to CrO_(x)-200.This valence states regulation of Cr species is indicated to provide more active sites for CO_(2) adsorption/activation and to modulate the reaction mechanism from single Cr site to Cr-Cr dual sites,thus endowing the superior CH_(4)production.This work demonstrates an alternative strategy for constructing efficient metal oxides cocatalysts on wide bandgap semiconductor.
基金the National Natural Science Foundation of China under Grant 21473183the open fund of Key Laboratory of Computational Physical Sciences(Fudan University),Ministry of Education.
文摘β-Ge3N4 loaded with nanoparticulate RuO2 as a cocatalyst is the first successful non-oxide photocatalyst for overall water splitting.To get an insight into the working mechanism of this particular photocatalytic system,we have calculated geometrical structures of low-index surfaces forβ-Ge3N4.Analysis of surface energies indicates that the most preferentially exposed surface is(100).The band gap of surface is narrower than that of bulk due to the dangling bonds.Dissociative water adsorption on(100)surface is thermodynamically favorable.The adsorption behavior of(RuO2)n(n=2,3,and 4)clusters on theβ-Ge3N4(100)surface has been explored.It is found that all the clusters bind to(100)surface strongly by forming interfacial bonds so that the adsorptions are exothermic processes.The calculation on density of states forβ-Ge3N4(100)surface loaded with(RuO2)nclusters reveals that photo-induced electrons tend to accumulate on(RuO2)nclusters and holes tend to stay inβ-Ge3N4.Based on the theoretical indication of Type-II staggered band alignment,we have proposed that in photocatalytic water splitting reaction,oxygen evolution reaction is inclined to occur on the surface ofβ-Ge3N4 while hydrogen evolution reaction is apt to occur on(RuO2)nclusters.In a word,loading RuO2 nanoparticles as a reduction cocatalyst benefits the charge separation inβ-Ge3N4.Furthermore,attaching(RuO2)nclusters ontoβ-Ge3N4(100)surface results in the redshift of absorption edge and the increase of absorption intensity.Our calculations have reasonably explained the experimental observation on the decomposition of water into H2 and O2 after loading RuO2 cocatalyst inβ-Ge3N4 photocatalyst.
文摘Aluminoxanes containing both ethyl and iso-butyl groups were synthesized by thehydrolysis of Al(C2H3)3 (TEA)/Al(i-C4H9)3 (TIBA) mixtures. The aluminoxane made from theTEA/TIBA mixture of molar ratio 7:3 showed cocatalyst activity of about five times as those ofethylaluminoxane or isobutylaluminoxane for ethylene polymerization catalyzed by Cp2ZrCl2. Thealuminoxane was characterized and the possible reasons for its high activity were discussed.
基金Supported by the National Natural Science Foundation of China(60910005)
文摘Based on the deficiency of catalytic elements in methane sensors such as sintering,activity decrease and surface area reduction at high temperature, three differentnano vectors Ce-Zr-Al_2O_3, Ce-Al_2O_3, and Zr-Al_2O_3 were prepared via sol-gel technique inthe experiment.BET surface area, catalytic activity and thermal stability were tested andcompared.It is found from the experiment that the Ce-doped Al_2O_3 vector possesseshigher catalytic activity than pure Al_2O_3 vector.Zr-doped Al_2O_3 vector can enhance thethermal stability of methane sensors.Ce-Zr-Al solid solution can be obtained by the presenceof Ce and Zr doped with Al_2O_3.The reaction activity and thermal stability of catalyticsensors were improved because of the unique synergy effect from Ce-Zr-O.Among themixed cocatalysts, Ce-Zr-O was reported to be an excellent cocatalyst material.The performanceof methane sensors can be improved significantly via the modification ofCe-Zr-Al_2O_3 vector.
基金supported by the Natural Science Foundation of Hebei of China(Nos.B2020205013,B2022205008)the Science and Technology Project of Hebei Normal University of China(No.L2021K01).
文摘Recently,Yu and co-workers deeply explore the potential impact of free electron transfer between co-catalysts and photocatalyst carriers on H_(2)evolution efficiency of active sites over MoS_(2+x).They pro-pose an electron-reversal tactics to evade the unexpected electron transfer and synchronously regulate the above transfer in a beneficial orientation for weakening hydrogen adsorption on S sites.Herein,this highlight not only discusses and summarizes the essences of electron reversal and the optimized H ad-sorption/desorption mechanism,but also emphasizes the significance of femtosecond transient absorp-tion spectroscopy(fs-TAS)and in-situ irradiated X-ray photoelectron spectroscopy(ISI-XPS)for revealing charge transfer dynamics and processes.We anticipate that this highlight can disseminate a new per-spective on the roles of photocatalyst carriers in improving cocatalytic H_(2)-production kinetics.
基金the National Natural Science Foundation of China(No.21603191)Zhejiang Provincial Natural Science Foundation of China(Nos.LY20B030003 and LQ16B010001)+2 种基金Public Welfare Technology Application Research Plan Project of Zhejiang Province(Analysis Test Item,No.2017C37024)Foundation of Science and Technology Bureau of Jinhua(No.20204185),Self-Topic Fund of Zhejiang Normal University(No.2020ZS04).
文摘Selective loading of spatially separated redox cocatalysts on direct Z-scheme heterojunctions holds great promise for advancing the efficiency of artificial photosynthesis,which however is limited to the photodeposition of noble metal cocatalysts and the fabrication of hollow double-shelled semiconductor heterojunctions.Moreover,the co-exposure of discrete cocatalyst and semiconductor increases the product diversity when both the exposed sites of which participate in CO_(2)photoreduction.Herein,we present a facile and versatile protocol to overcome these limitations via surface coating of Z-scheme heterojunctions with bifunctional noble-metal-free cocatalysts.With Cu_(2)O/Fe_(2)O_(3)(CF)as a model heterojunction and layered Ni(OH)_(2)as a model cocatalyst,it is found that Ni(OH)_(2)lying on the surfaces of Cu_(2)O and Fe_(2)O_(3)separately co-catalyzes the CO_(2)reduction and H_(2)O oxidation.Thorough experimental and theoretical investigation reveals that the Ni(OH)_(2)outer layer:(i)mitigates the charge recombination in CF and balances their transfer and consumption;(ii)reduces the rate-determining barriers for CO_(2)-to-CO and H_(2)O-to-O_(2)conversion,(iii)suppresses the side proton reduction occurring on CF,and(iv)protects the CF from component detachment.As expected,the redox reactions stoichiometrically proceed,and significantly enhanced photocatalytic activity,selectivity,and stability in CO generation are achieved by the stacked Cu_(2)O/Fe_(2)O_(3)@Ni(OH)_(2)in contrast to CF.This study demonstrates the significance of the synergy between bifunctional cocatalysts and Z-scheme heterojunctions for improving the efficacy of overall redox reactions,opening a fresh avenue for the rational design of artificial photosynthetic systems.
基金supported by the National Re-search Foundation of Korea(Nos.NRF-2020R1C1C1008514,2019R1A6A1A11053838,and NRF-2023R1A2C1004015)the“Regional Innovation Strategy(RIS)”through the National Research Foundation of Korea(NRF)funded by the Ministry of Education(MOE)(No.2021RIS-003).
文摘The visible-light-driven hydrogen evolution is extremely important,but the poor charge transfer capa-bility,a sluggish evolution rate of hydrogen,and severe photo-corrosion make photocatalytic hydrogen evolution impractical.In this study,we present 1D/2D ReS_(2)-CdS hybrid nanorods for photocatalytic hy-drogen evolution,comprised of a ReS_(2)nanosheet layer grown on CdS nanorods.We found that precise control of the contents of the ReS_(2)nanosheet layer allows for manipulating the electronic structure of Re in the ReS_(2)-CdS hybrid nanorods.The ReS_(2)-CdS hybrid nanorods with optimal ReS_(2)nanosheet layer content dramatically improve photocatalytic hydrogen evolution activity.Notably,photocatalytic hydro-gen evolution activity(64.93 mmol g^(−1)h^(−1))of ReS_(2)-CdS hybrid nanorods with ReS_(2)nanosheet layers(Re/Cd atomic ratio of 0.051)is approximately 136 times higher than that of pure CdS nanorods under visible light irradiation.Furthermore,intimated coupling of the ReS_(2)nanosheet layer with CdS nanorods reduced the surface trap-site of the CdS nanorods,resulting in enhanced photocatalytic stability.The de-tailed optical and electrical investigations demonstrate that the optimal ReS_(2)nanosheet layer contents in the ReS_(2)-CdS hybrid nanorods can provide improved charge transfer capability,catalytic activity,and light absorption efficiency.This study sheds light on the development of photocatalysts for highly efficient photocatalytic hydrogen evolution.
文摘Metal halide perovskite(MHP)has become one of the most promising materials for photocatalytic CO_(2)reduction owing to the wide light absorption range,negative conduction band position and high reduction ability.However,photoreduction of CO_(2)by MHP remains a challenge because of the slow charge separation and transfer.Herein,a cobalt single-atom modified nitrogen-doped graphene(Co-NG)cocatalyst is prepared for enhanced photocatalytic CO_(2)reduction of bismuth-based MHP Cs_(3)Bi_(2)Br_(9).The optimal Cs_(3)Bi_(2)Br_(9)/Co-NG composite exhibits the CO production rate of 123.16μmol g-1 h-1,which is 17.3 times higher than that of Cs_(3)Bi_(2)Br_(9).Moreover,the Cs_(3)Bi_(2)Br_(9)/Co-NG composite photocatalyst exhibits nearly 100%CO selectivity as well as impressive long-term stability.Charge carrier dynamic characterizations such as Kelvin probe force microscopy(KPFM),single-particle PL microscope and transient absorption(TA)spectroscopy demonstrate the vital role of Co-NG cocatalyst in accelerating the transfer and separation of photogenerated charges and improving photocatalytic performance.The reaction mechanism has been demonstrated by in situ diffuse reflectance infrared Fourier-transform spectroscopy measurement.In addition,in situ X-ray photoelectron spectroscopy test and theoretical calculation reveal the reaction reactive sites and reaction energy barriers,demonstrating that the introduction of Co-NG promotes the formation of~(*)COOH intermediate,providing sufficient evidence for the highly selective generation of CO.This work provides an effective single-atom-based cocatalyst modification strategy for photocatalytic CO_(2)reduction and is expected to shed light on other photocatalytic applications.
基金financially supported by the Natural Science Foundation of Henan Province(No.212300410336)Program for Science and Technology Innovation Talent in Universities of Henan Province(No.20HASTIT016)National Natural Science Foundation of China(No.51902101)。
文摘Molybdenum disulfide(Mo S_(2))has attracted great attention in hydrogen peroxide(H_(2)O_(2))activation as a Fenton-like catalyst and cocatalyst,but the distinct mechanism of generating^(·)OH remains unclear.In this paper,the metallic 1T phase and semiconducting 2H phase of Mo S_(2)nanosheets were prepared and applied in MoS_(2)/H_(2)O_(2)and MoS_(2)/Fe^(2+)/H_(2)O_(2)systems with and without light irradiation.Compared with2H-MoS_(2),1T-MoS_(2)exhibited superior removal rates in degrading organic pollutants in the two systems under light irradiation.However,the phase had little effect on activating H_(2)O_(2)in the Mo S_(2)/H_(2)O_(2)system under dark conditions.This is because it was difficult for the surface^(·)OH_(ads)generated in the Mo S_(2)/H_(2)O_(2)system to diffuse into solution,while the^(·)OH_(free)radicals were mainly responsible for degrading organic pollutants.When introducing light irradiation,external energy may accelerate the desorption of^(·)OH_(ads)into^(·)OH_(free.)Interestingly,the conversion between Mo^(4+)and Mo^(5+)triggered the decomposition of H_(2)O_(2)in the Fenton-like reaction,while the cycle of Mo^(4+)/Mo^(6+)promoted the regeneration of Fe^(3+)when employing 1T-MoS_(2)as a cocatalyst.Meanwhile,the 1T-MoS_(2)catalysts exhibited excellent stability and ability to degrade various organics in the two systems.This work offers deeper insight into the Mo S_(2)-based Fenton-like and cocatalytic mechanisms.
基金financially supported from the National Natural Science Foundation of China (22209084)the Yongjiang Talent Project (2021A-142-G)+2 种基金the Natural Science Foundation of Ningbo (2021J066)the starting-up funding of Ningbo University (422109273)K.C.Wong Magna Fund in Ningbo University。
文摘Photocatalysis, which performed under mild conditions by utilizing solar energy, has become a desirable technology to convert methane into highly valuable chemicals, such as methanol, ethane, and other hydrocarbons. However, pristine photocatalysts still suffer from the low utilization efficiency of solar light and the high recombination rate of photogenerated charge carriers, which exhibit the low activity and selectivity for photocatalytic methane conversion. Loading cocatalysts on photocatalysts is an attractive strategy to manipulate the products' yield and selectivity of photocatalytic methane conversion due to the enhanced charge carrier separation efficiency, extended light absorption and promoted reactant adsorption/desorption kinetics. This review discusses the recent achievements of the cocatalysts for photocatalytic methane conversion reactions. Moreover, the challenges and perspectives for the development of efficient cocatalysts are presented. This review provides considerable guidelines for the design and construction of efficient cocatalysts for photocatalytic methane conversion reactions.
基金supported by the Program for the National Natural Science Foundation of China(No.21972058)Prof.H.Tang also appreciates the support from the Taishan Youth Scholar Program of Shandong Province.
文摘Aiming to develop a photocatalyst that can simultaneously produce valuable chemicals and clean H_(2) fuel for promoting the utilization efficiency of solar energy,herein,a sea-urchin-like CoP@Ni_(2)P binary nanojunction was employed as an efficient photothermal cocatalyst to couple with zero-dimensional CdZnS(CZS)solid solution for achieving superior coordinative redox reaction.The CoP@Ni_(2)P/CZS hybrid displayed a high solar-driven H_(2) generation rate of 40.92 mmol g^(–1) h^(–1) coupling with a benzaldehyde formation rate of 20.33 mmol g^(–1) h^(–1),which was 16.4 and 8.0 times higher than that of bare CZS.Furthermore,the CoP@Ni_(2)P/CZS hybrid also achieved a high photothermal H_(2) production under a broad light range from 420 to 720 nm,and the H_(2) production reached 44.48μmol g^(–1) h^(–1) under the 720 nm light illumination.The enhanced catalytic performance can be ascribed to that the CoP@Ni_(2)P nanojunction with photothermal effect can speed up the separation and transport of carriers,offer more catalytic active sites,and induce an increase in temperature to optimize reaction kinetics.This study may open a facile route to design novel binary metal phosphides with dual functions in photocatalysis for the full exploitation of solar energy.
基金This work was supported by the National Natural Science Foundation of China(No.22178275)the Natural Science Foundation of Hubei Province of China(No.2022CFA001).
文摘Traditional bulk MoS_(2) as an effective H_(2)-evolution cocatalyst is mainly subjected to the weak hydrogen-adsorption ability of highporpotion saturated S,resulting in a slow interfacial H_(2)-evolution reaction.In this paper,an efficient strategy for enhancing hydrogen adsorption of saturated S by manipulating electron density through O atoms is proposed to boost photocatalytic performance of CdS.Simultaneously,amorphization of MoS_(2) can further increase the unsaturated active S sites.Herein,oxygencontained amorphous MoS_(x)(a-MoOS_(x))nanoparticles(10-30 nm)were tightly loaded on the CdS surface through a mild photoinduced deposition method by using(NH_(4))_(2)[MoO(S_(4))_(2)]solution as the precursor at room temperature.The photocatalytic H_(2)-evolution result showed that the a-MoOS_(x)/CdS performed the superior H_(2)-production activity(382μmol·h^(-1),apparent quantum efficiencies(AQE)=11.83%)with a lot of visual H_(2)bubbles,which was 54.6,2.5,and 5.1 times as high as that of CdS,MoS_(x)/CdS,and annealed a-MoOS_(x)/CdS,respectively.Characterizations and density functional theory(DFT)calculations revealed the mechanism of improved H_(2)-evolution activity is that the O heteroatom in amorphous MoOS_(x) can enhance the atomic H-adsorption ability by manipulating the electron density to form electron-deficient S^((2-δ)-)sites.This study provides a new idea to improve the efficiency and number of H_(2)-evolution active sites for developing efficient cocatalysts in the field of photocatalytic hydrogen evolution.