In this work,a novel plasmon-assisted UV-vis-NIR-driven W_(18)O_(49)/Cd_(0.5)Zn_(0.5)S heterostructure photocatalyst was obtained by a facile ultrasonic-assisted electrostatic self-assembly strategy.The hybrid exhibit...In this work,a novel plasmon-assisted UV-vis-NIR-driven W_(18)O_(49)/Cd_(0.5)Zn_(0.5)S heterostructure photocatalyst was obtained by a facile ultrasonic-assisted electrostatic self-assembly strategy.The hybrid exhibits extraordinary H2 evolution activity of 147.7 mmol·g^(-1)·h^(-1) at room temperature due to the efficient charge separation and expanded light absorption.Our investigation shows that the unique Step-scheme(S-scheme)charge transfer and the‘hot electron’injection are both responsible for the extraordinary H2 evolution process,depending on the wavelength of the incident light.Moreover,by accelerating the surface reaction kinetics,the activity can be further elevated to 306.1 mmol·g^(-1)·h^(-1),accompanied by a high apparent quantum yield of 45.3% at 365±7.5 nm.This work provides us a potential strategy for the highly efficient conversion of the solar energy by elaborately combining a nonstoichiometric ratio plasmonic material with an appropriate active photocatalyst.展开更多
The design and construction of low‐cost and high‐performance hybrid materials for the photocatalytic hydrogen production reaction(HER)are extremely important for the large‐scale application of hydrogen energy.Metal...The design and construction of low‐cost and high‐performance hybrid materials for the photocatalytic hydrogen production reaction(HER)are extremely important for the large‐scale application of hydrogen energy.Metal‐organic frameworks(MOFs)are considered to be potential photocatalytic materials.Herein,monodisperse,small size,non‐precious metal transition metal phosphide Ni2P is encapsulated into a typical MOF(UiO‐66‐NH2)as a hybrid core‐shell cocatalyst to modify Zn_(0.5)Cd_(0.5)S for photocatalytic hydrogen production.Ni2P is wrapped in UiO‐66‐NH_(2)via an in situ solvothermal method,and Zn_(0.5)Cd_(0.5)S sulfide is decorated with a core‐shell Ni_(2)P@UiO‐66‐NH_(2)cocatalyst to obtain ternary Ni_(2)P@UiO‐66‐NH_(2)/Zn_(0.5)Cd_(0.5)S composite materials.Photoelectric and chemical characterization confirms that the ternary composites have good kinetic hydrogen production performance.The hydrogen production rate of 10%10 mg Ni_(2)P@UiO‐66‐NH_(2)/Zn_(0.5)Cd_(0.5)S reaches 40.91 mmol·g^(–1)·h^(–1)with an apparent quantum efficiency at 420 nm of 13.57%.The addition of 10 mg Ni_(2)P@UiO‐66‐NH_(2)increases the surface area of the ternary material,providing abundant reaction sites and forming an efficient charge transfer channel,which is conducive to efficient hydrogen production by the ternary photocatalysts.It is shown that the formation of a ternary composite system is beneficial to the occurrence of an efficient catalytic reaction.This study provides a new perspective for the construction of high‐performance photocatalytic materials.展开更多
The development of distinguished photocatalysts with high photo-carrier disassociation and photo-redox power for efficient elimination of pollutants in water is of great significance but still a grand challenge.Herein...The development of distinguished photocatalysts with high photo-carrier disassociation and photo-redox power for efficient elimination of pollutants in water is of great significance but still a grand challenge.Herein,a novel Cd_(0.5)Zn_(0.5)S/Bi_(2)WO_(6) S-scheme heterojunction was built up by integrating Cd0.5Zn0.5S nanoparticles on Bi2WO6 microspheres via a simple route.The S-scheme charge transfer mode substantially boosts the high-energetic electrons/holes spatial detachment and conservation on the Cd_(0.5)Zn_(0.5)S(reduction)and Bi_(2)WO_(6)(oxidation),respectively,as well as effectively suppresses the photo-corrosion of Cd_(0.5)Zn_(0.5)S,rendering Cd_(0.5)Zn_(0.5)S/Bi_(2)WO_(6) photocatalysts with superior redox ability.The optimal Cd_(0.5)Zn_(0.5)S/Bi_(2)WO_(6) heterojunction achieves exceptional visible-light-driven photocatalytic tetracycline degradation and Cr(VI)reduction efficiency,3.2(1.9)-time and 33.6(1.6)-time stronger than that of neat Bi_(2)WO_(6)(Cd_(0.5)Zn_(0.5)S),while retaining the superior stability and reusability.Quenching test,mass spectrometry analysis,and toxicity assessment based on Quantitative Structure Activity Relationships.calculation unravel the prime active substances,intermediates,photo-degradation pathway,and intermediate eco-toxicity in photocatalytic process.This research not only offers a potential photocatalyst for aquatic environment protection but also promotes the exploration of novel and powerful chalcogenides-based S-scheme photocatalysts for environment protection.展开更多
Different components of PtPd bimetallic cocatalysts modified Zn_(0.5)Cd_(0.5)S nanorods have already been designed and prepared in this study.The obtained hybrid photocatalysts were tested and characterized by XPS,ICP...Different components of PtPd bimetallic cocatalysts modified Zn_(0.5)Cd_(0.5)S nanorods have already been designed and prepared in this study.The obtained hybrid photocatalysts were tested and characterized by XPS,ICP-OES and UV-Vis spectra,TEM and EDX tools.Such characterizations can prove the formation of PtPd bimetallic alloy particles in hybrid catalysts.Under visible light illumination,an outstanding hydrogen producing rate of 9.689mmol·g^(-1)·h^(-1) and a high AQY efficiency up to 10.43%at 420 nm are achieved in this work.In addition,thermodynamics(DFT calculations)and kinetics(Photoluminescence emission,photocurrent responses,electrochemical impedance spectroscopy and surface photovoltage spectra)investigations illustrate that PtPd bimetallic alloy has similar catalytic thermodynamic properties to Pt,which can greatly boost the charge separation and speed up the charge transfer,and decrease the activation energy of H2 generation.Notably,the calculation data suggests that Pt is thermodynamically favorable,while PtPd alloy is kinetically beneficial to H_(2)production,which can be ascribed to the higher activity of PtPd/Zn_(0.5)Cd_(0.5)S than Pt/Zn_(0.5)Cd_(0.5)S.This work can propose a fresh perspective for preparing high efficiency hybrid photocatalysts.展开更多
Designing and fabricating highly efficient photocatalysts for water splitting is a promising strategy to address energy and environmental issues.Cadmium sulfide(CdS)has received significant interest as a photocatalyst...Designing and fabricating highly efficient photocatalysts for water splitting is a promising strategy to address energy and environmental issues.Cadmium sulfide(CdS)has received significant interest as a photocatalyst for visible‐light‐induced hydrogen(H2)generation.However,the severe photocorrosion,high overpotential,rapid charge recombination,and sluggish surface reaction kinetics drastically hinder its practical application in water splitting.Herein,uniform zinc cadmium sulfide(Zn_(0.5)Cd_(0.5)S)nanoparticles were anchored on ultrathin Ni(OH)_(2)nanosheets via a facile solution‐phase approach to form an intimate two‐dimensional(2D)/zero‐dimensional(0D)heterojunction.Under visible light irradiation,the 7%Ni(OH)_(2)/Zn_(0.5)Cd_(0.5)S composite exhibited the highest H2 production rate of 6.87 mmol·h^(–1)·g^(–1)with an apparent quantum yield of 16.8%at 420 nm,which is almost 43 times higher than that of pristine Zn_(0.5)Cd_(0.5)S and considerably higher than that of the Pt/Zn_(0.5)Cd_(0.5)S photocatalyst.The high photoactivity of the 2D/0D Ni(OH)_(2)/Zn_(0.5)Cd_(0.5)S heterojunction can be ascribed to its unique and robust structure,wherein the ultrathin Ni(OH)_(2)nanosheets not only provide an excellent platform for the incorporation of Zn_(0.5)Cd_(0.5)S nanoparticles but also serve as an effective cocatalyst to promote photoinduced electron transfer and offer more active sites for photocatalytic H_(2) generation.This work paves the way toward the development of versatile,low‐cost,and highly efficient 2D/0D heterojunction photocatalysts for solar energy conversion.展开更多
Cd_(0.5)Zn_(0.5)S/g-C_(3)N_(4)(CZS/CN)step-like heterojunction composites were facilely synthesized by annealing a sandwich of cadmium-zinc-thiourea precursors in one pot.The types of the used raw materials and the pr...Cd_(0.5)Zn_(0.5)S/g-C_(3)N_(4)(CZS/CN)step-like heterojunction composites were facilely synthesized by annealing a sandwich of cadmium-zinc-thiourea precursors in one pot.The types of the used raw materials and the preparation procedure were simplified as much as possible in this work.The obtained hybrid exhibited enlarged specific surface area and higher separation/transfer efficiency of charge carriers compared to pure Cd_(0.5)Zn_(0.5)S and g–C_(3)N_(4),thus exhibited much enhanced photocatalytic efficiency for dye degradation under visible-light irradiation.The interfacial charge-transfer mechanism of the formed step-scheme(Sscheme)heterojunction between Cd_(0.5)Zn_(0.5)S and g–C_(3)N_(4) were carefully investigated and discussed.This work could widen the application prospect of the Cd_(x)Zn_(1-x)S/g-C_(3)N_(4) composite and provide new ideas to the design and fabrication of novel heterojunctions with robust photocatalytic performance.展开更多
Converting water into hydrogen fuel and oxidizing benzyl alcohol to benzaldehyde simultaneously under visible light illumination is of great significance,but the fast recombination of photogenerated carriers in photoc...Converting water into hydrogen fuel and oxidizing benzyl alcohol to benzaldehyde simultaneously under visible light illumination is of great significance,but the fast recombination of photogenerated carriers in photocatalysts seriously decreases the conversion efficiency.Herein,a novel dual-functional 0D Cd_(0.5)Zn_(0.5)S/2D Ti_(3)C2 hybrid was fabricated by a solvothermally in-situ generated assembling method.The Cd_(0.5)Zn_(0.5)S nano-spheres with a fluffy surface completely and uniformly covered the ultrathin Ti_(3)C2 nanosheets,leading to the increased Schottky barrier(SB)sites due to a large contact area,which could accelerate the electron–hole separation and improve the light utilization.The optimized Cd_(0.5)Zn_(0.5)S/Ti_(3)C2 hybrid simultaneously presents a hydrogen evolution rate of 5.3 mmol/(g·h)and a benzaldehyde production rate of 29.3 mmol/(g·h),which are~3.2 and 2 times higher than those of pristine Cd_(0.5)Zn_(0.5)S,respectively.Both the multiple experimental measurements and the density functional theory(DFT)calculations further demonstrate the tight connection between Cd_(0.5)Zn_(0.5)S and Ti_(3)C2,formation of Schottky junction,and efficient photogenerated electron–hole separation.This paper suggests a dual-functional composite catalyst for photocatalytic hydrogen evolution and benzaldehyde production,and provides a new strategy for preventing the photogenerated electrons and holes from recombining by constructing a 0D/2D heterojunction with increased SB sites.展开更多
The development of highly efficient catalyst is the key for photocatalytic technology to deal with water pollution and energy problems.In this work,the S-scheme polyaniline/Cd_(0.5)Zn_(0.5)S(PANI/CZS)nanocomposites we...The development of highly efficient catalyst is the key for photocatalytic technology to deal with water pollution and energy problems.In this work,the S-scheme polyaniline/Cd_(0.5)Zn_(0.5)S(PANI/CZS)nanocomposites were elaborately prepared for the first time by in-situ oxidation polymerization.Compared to pure PANI and Cd_(0.5)Zn_(0.5)S,this PANI/CZS hybrid displayed outstanding photocatalytic performance in removing tetracycline hydrochloride(TCH)and hydrogen evolution under light irradiation.Among them,15 PANI/CZS sample could achieve 84.9%TCH degradation efficiency within 25 min,and the degradation rate(0.06931 min−1)was 5.13 times than that of Cd_(0.5)Zn_(0.5)S(0.0135 min^(−1)).The optimal photocatalytic H_(2) evolution rate of 30 PANI/CZS sample was 15.57 mmol g^(-1) h^(-1),which was twice that of Cd_(0.5)Zn_(0.5)S(7.34 mmol g^(-1) h^(-1)).These results were mainly attributed to the efficient electronic transport channels provided by S-scheme heterojunction structure.The density functional theory(DFT)calculation proved that the difference of work function resulted in band bending and forming built-in electric field on the contact interface of PANI/CZS,which facilitated the migration and separation of interfacial photogener-ated charge carriers for the strengthened photocatalytic performance.Further,the degradation interme-diate products and pathways of TCH were also put forwarded in depth based on MS experiment.At last,the S-scheme electron transport model and the photocatalytic reaction mechanism in PANI/CZS hetero-junction structure were studied.This work provided an innovative vision in developing high-performance S-scheme heterojunction multifunctional photocatalysts.展开更多
In recent years,many effective photocatalysts have been developed to solve the problem of environmental pollution and clean energy shortage.In this paper,non-noble metal cocatalyst Ni_(3)N nanoparticles supported Zn_(...In recent years,many effective photocatalysts have been developed to solve the problem of environmental pollution and clean energy shortage.In this paper,non-noble metal cocatalyst Ni_(3)N nanoparticles supported Zn_(0.5)Cd_(0.5)S(ZCS)nanorods(Ni_(3)N/ZCS)composites were successfully synthesized by ultrasonic method.The hydrogen production efficiencies of the photocatalysts were tested under visible light,which was found that when the loading of Ni_(3)N was 2%of the mass of ZCS,and the Ni_(3)N/ZCS composite had the best hydrogen evolution performance,which could reach 70.3 mmol·h^(-1)·g^(-1).In addition,the quantum efficiency under 420 nm monochromatic light irradiation was 27.2%.Through different characterization analyses,such as X-ray diffraction(XRD),scanning electron microscopy(SEM),and UV-Vis diffuse reflectance spectra(DRS),a possible photocatalytic mechanism was proposed,providing some reference values for non-precious metals as cocatalysts.展开更多
Photocatalytic water splitting for hydrogen(H_(2))production is a green sustainable technology,in which highly-efficient steady photocatalysts are fundamentally required.In this work,unique CdS/Cd_(0.5)Zn_(0.5)S-M0_(1...Photocatalytic water splitting for hydrogen(H_(2))production is a green sustainable technology,in which highly-efficient steady photocatalysts are fundamentally required.In this work,unique CdS/Cd_(0.5)Zn_(0.5)S-M0_(1-x)W_(x)S_(2) photocatalyst constructed by CdS hollow nano-spheres with successively surface-modified Cd_(0.5)Zn_(0.5)S shell and defect-rich MO_(1-x)W_(x)S_(2) ultrathin nanosheets was reported for the first time.Interestingly,the Cd_(0.5)Zn_(0.5)S shell could greatly enhance the photo-stability and reduce the carrier recombination of CdS.Meanwhile,enriching active sites and accelerating charge transfer could be achieved via anchoring defect-rich Mo_(1-x)W_(x)S_(2) onto CdS/Cd_(0.5)Zn_(0.5)S hollow heterostructures.Specifically,the optimized CdS/Cd_(0.5)Zn_(0.5)S-Mo_(1-x)W_(x)Sa(6 h Cd_(0.5)Zn_(0.5)S-coating,7 wt.%Mo_(1-x)W_(x)S_(2),x=0.5)hybrid delivered an exceptional H_(2) generation rate of 215.99 mmol·g^(-1)·h^(-1),which is approximately 502,134,and 23 times that of pure CdS,CdS/Cd_(0.5)Zn_(0.5)S,and 3 wt.%Pt-loaded CdS/Cd_(0.5)Zn_(0.5)S,respectively.Remarkably,a high H_(2) evolution reaction(HER)apparent quantum yield(AQY)of 64.81%was obtained under 420-nm irradiation.In addition,the CdS/Cd_(0.5)Zn_(0.5)S-Mo_(1-x)W_(x)S_(2) was also durable for H2 production under long-term irradiation.This work provides valuable inspirations to rational design and synthesis of efficient and stable hybrid photocatalysts for solar energy conversion.展开更多
文摘In this work,a novel plasmon-assisted UV-vis-NIR-driven W_(18)O_(49)/Cd_(0.5)Zn_(0.5)S heterostructure photocatalyst was obtained by a facile ultrasonic-assisted electrostatic self-assembly strategy.The hybrid exhibits extraordinary H2 evolution activity of 147.7 mmol·g^(-1)·h^(-1) at room temperature due to the efficient charge separation and expanded light absorption.Our investigation shows that the unique Step-scheme(S-scheme)charge transfer and the‘hot electron’injection are both responsible for the extraordinary H2 evolution process,depending on the wavelength of the incident light.Moreover,by accelerating the surface reaction kinetics,the activity can be further elevated to 306.1 mmol·g^(-1)·h^(-1),accompanied by a high apparent quantum yield of 45.3% at 365±7.5 nm.This work provides us a potential strategy for the highly efficient conversion of the solar energy by elaborately combining a nonstoichiometric ratio plasmonic material with an appropriate active photocatalyst.
文摘The design and construction of low‐cost and high‐performance hybrid materials for the photocatalytic hydrogen production reaction(HER)are extremely important for the large‐scale application of hydrogen energy.Metal‐organic frameworks(MOFs)are considered to be potential photocatalytic materials.Herein,monodisperse,small size,non‐precious metal transition metal phosphide Ni2P is encapsulated into a typical MOF(UiO‐66‐NH2)as a hybrid core‐shell cocatalyst to modify Zn_(0.5)Cd_(0.5)S for photocatalytic hydrogen production.Ni2P is wrapped in UiO‐66‐NH_(2)via an in situ solvothermal method,and Zn_(0.5)Cd_(0.5)S sulfide is decorated with a core‐shell Ni_(2)P@UiO‐66‐NH_(2)cocatalyst to obtain ternary Ni_(2)P@UiO‐66‐NH_(2)/Zn_(0.5)Cd_(0.5)S composite materials.Photoelectric and chemical characterization confirms that the ternary composites have good kinetic hydrogen production performance.The hydrogen production rate of 10%10 mg Ni_(2)P@UiO‐66‐NH_(2)/Zn_(0.5)Cd_(0.5)S reaches 40.91 mmol·g^(–1)·h^(–1)with an apparent quantum efficiency at 420 nm of 13.57%.The addition of 10 mg Ni_(2)P@UiO‐66‐NH_(2)increases the surface area of the ternary material,providing abundant reaction sites and forming an efficient charge transfer channel,which is conducive to efficient hydrogen production by the ternary photocatalysts.It is shown that the formation of a ternary composite system is beneficial to the occurrence of an efficient catalytic reaction.This study provides a new perspective for the construction of high‐performance photocatalytic materials.
文摘The development of distinguished photocatalysts with high photo-carrier disassociation and photo-redox power for efficient elimination of pollutants in water is of great significance but still a grand challenge.Herein,a novel Cd_(0.5)Zn_(0.5)S/Bi_(2)WO_(6) S-scheme heterojunction was built up by integrating Cd0.5Zn0.5S nanoparticles on Bi2WO6 microspheres via a simple route.The S-scheme charge transfer mode substantially boosts the high-energetic electrons/holes spatial detachment and conservation on the Cd_(0.5)Zn_(0.5)S(reduction)and Bi_(2)WO_(6)(oxidation),respectively,as well as effectively suppresses the photo-corrosion of Cd_(0.5)Zn_(0.5)S,rendering Cd_(0.5)Zn_(0.5)S/Bi_(2)WO_(6) photocatalysts with superior redox ability.The optimal Cd_(0.5)Zn_(0.5)S/Bi_(2)WO_(6) heterojunction achieves exceptional visible-light-driven photocatalytic tetracycline degradation and Cr(VI)reduction efficiency,3.2(1.9)-time and 33.6(1.6)-time stronger than that of neat Bi_(2)WO_(6)(Cd_(0.5)Zn_(0.5)S),while retaining the superior stability and reusability.Quenching test,mass spectrometry analysis,and toxicity assessment based on Quantitative Structure Activity Relationships.calculation unravel the prime active substances,intermediates,photo-degradation pathway,and intermediate eco-toxicity in photocatalytic process.This research not only offers a potential photocatalyst for aquatic environment protection but also promotes the exploration of novel and powerful chalcogenides-based S-scheme photocatalysts for environment protection.
文摘Different components of PtPd bimetallic cocatalysts modified Zn_(0.5)Cd_(0.5)S nanorods have already been designed and prepared in this study.The obtained hybrid photocatalysts were tested and characterized by XPS,ICP-OES and UV-Vis spectra,TEM and EDX tools.Such characterizations can prove the formation of PtPd bimetallic alloy particles in hybrid catalysts.Under visible light illumination,an outstanding hydrogen producing rate of 9.689mmol·g^(-1)·h^(-1) and a high AQY efficiency up to 10.43%at 420 nm are achieved in this work.In addition,thermodynamics(DFT calculations)and kinetics(Photoluminescence emission,photocurrent responses,electrochemical impedance spectroscopy and surface photovoltage spectra)investigations illustrate that PtPd bimetallic alloy has similar catalytic thermodynamic properties to Pt,which can greatly boost the charge separation and speed up the charge transfer,and decrease the activation energy of H2 generation.Notably,the calculation data suggests that Pt is thermodynamically favorable,while PtPd alloy is kinetically beneficial to H_(2)production,which can be ascribed to the higher activity of PtPd/Zn_(0.5)Cd_(0.5)S than Pt/Zn_(0.5)Cd_(0.5)S.This work can propose a fresh perspective for preparing high efficiency hybrid photocatalysts.
文摘Designing and fabricating highly efficient photocatalysts for water splitting is a promising strategy to address energy and environmental issues.Cadmium sulfide(CdS)has received significant interest as a photocatalyst for visible‐light‐induced hydrogen(H2)generation.However,the severe photocorrosion,high overpotential,rapid charge recombination,and sluggish surface reaction kinetics drastically hinder its practical application in water splitting.Herein,uniform zinc cadmium sulfide(Zn_(0.5)Cd_(0.5)S)nanoparticles were anchored on ultrathin Ni(OH)_(2)nanosheets via a facile solution‐phase approach to form an intimate two‐dimensional(2D)/zero‐dimensional(0D)heterojunction.Under visible light irradiation,the 7%Ni(OH)_(2)/Zn_(0.5)Cd_(0.5)S composite exhibited the highest H2 production rate of 6.87 mmol·h^(–1)·g^(–1)with an apparent quantum yield of 16.8%at 420 nm,which is almost 43 times higher than that of pristine Zn_(0.5)Cd_(0.5)S and considerably higher than that of the Pt/Zn_(0.5)Cd_(0.5)S photocatalyst.The high photoactivity of the 2D/0D Ni(OH)_(2)/Zn_(0.5)Cd_(0.5)S heterojunction can be ascribed to its unique and robust structure,wherein the ultrathin Ni(OH)_(2)nanosheets not only provide an excellent platform for the incorporation of Zn_(0.5)Cd_(0.5)S nanoparticles but also serve as an effective cocatalyst to promote photoinduced electron transfer and offer more active sites for photocatalytic H_(2) generation.This work paves the way toward the development of versatile,low‐cost,and highly efficient 2D/0D heterojunction photocatalysts for solar energy conversion.
基金financially supported by the National Natural Science Foundation of China(Nos.21972171 and 51672312)the Fundamental Research Funds for the Central Universities,South Central University for Nationalities(No.CZT20016)。
文摘Cd_(0.5)Zn_(0.5)S/g-C_(3)N_(4)(CZS/CN)step-like heterojunction composites were facilely synthesized by annealing a sandwich of cadmium-zinc-thiourea precursors in one pot.The types of the used raw materials and the preparation procedure were simplified as much as possible in this work.The obtained hybrid exhibited enlarged specific surface area and higher separation/transfer efficiency of charge carriers compared to pure Cd_(0.5)Zn_(0.5)S and g–C_(3)N_(4),thus exhibited much enhanced photocatalytic efficiency for dye degradation under visible-light irradiation.The interfacial charge-transfer mechanism of the formed step-scheme(Sscheme)heterojunction between Cd_(0.5)Zn_(0.5)S and g–C_(3)N_(4) were carefully investigated and discussed.This work could widen the application prospect of the Cd_(x)Zn_(1-x)S/g-C_(3)N_(4) composite and provide new ideas to the design and fabrication of novel heterojunctions with robust photocatalytic performance.
基金This work was supported by the National Natural Science Foundation of China(Grant Nos.51902137 and 51672113)the Key Research and Development Plan(Grant No.BE2019094)+1 种基金the Qing Lan Project([2016]15)of Jiangsu ProvinceThe calculations were carried out by the Advanced Computing East China Sub-center and Big Data Center of Southeast University。
文摘Converting water into hydrogen fuel and oxidizing benzyl alcohol to benzaldehyde simultaneously under visible light illumination is of great significance,but the fast recombination of photogenerated carriers in photocatalysts seriously decreases the conversion efficiency.Herein,a novel dual-functional 0D Cd_(0.5)Zn_(0.5)S/2D Ti_(3)C2 hybrid was fabricated by a solvothermally in-situ generated assembling method.The Cd_(0.5)Zn_(0.5)S nano-spheres with a fluffy surface completely and uniformly covered the ultrathin Ti_(3)C2 nanosheets,leading to the increased Schottky barrier(SB)sites due to a large contact area,which could accelerate the electron–hole separation and improve the light utilization.The optimized Cd_(0.5)Zn_(0.5)S/Ti_(3)C2 hybrid simultaneously presents a hydrogen evolution rate of 5.3 mmol/(g·h)and a benzaldehyde production rate of 29.3 mmol/(g·h),which are~3.2 and 2 times higher than those of pristine Cd_(0.5)Zn_(0.5)S,respectively.Both the multiple experimental measurements and the density functional theory(DFT)calculations further demonstrate the tight connection between Cd_(0.5)Zn_(0.5)S and Ti_(3)C2,formation of Schottky junction,and efficient photogenerated electron–hole separation.This paper suggests a dual-functional composite catalyst for photocatalytic hydrogen evolution and benzaldehyde production,and provides a new strategy for preventing the photogenerated electrons and holes from recombining by constructing a 0D/2D heterojunction with increased SB sites.
基金supported by National Natural Science Foundation of China (Nos.21777062,22178151 and 51872128)National&Local Joint Engineering Research Center for Mineral Salt Deep Utilization of Huaiyin Institute of Technology (Nos.SF202008,SF202204 and SF202106)Guangdong Basic and Applied Basic Research Foundation (No.2021A1515111231).
文摘The development of highly efficient catalyst is the key for photocatalytic technology to deal with water pollution and energy problems.In this work,the S-scheme polyaniline/Cd_(0.5)Zn_(0.5)S(PANI/CZS)nanocomposites were elaborately prepared for the first time by in-situ oxidation polymerization.Compared to pure PANI and Cd_(0.5)Zn_(0.5)S,this PANI/CZS hybrid displayed outstanding photocatalytic performance in removing tetracycline hydrochloride(TCH)and hydrogen evolution under light irradiation.Among them,15 PANI/CZS sample could achieve 84.9%TCH degradation efficiency within 25 min,and the degradation rate(0.06931 min−1)was 5.13 times than that of Cd_(0.5)Zn_(0.5)S(0.0135 min^(−1)).The optimal photocatalytic H_(2) evolution rate of 30 PANI/CZS sample was 15.57 mmol g^(-1) h^(-1),which was twice that of Cd_(0.5)Zn_(0.5)S(7.34 mmol g^(-1) h^(-1)).These results were mainly attributed to the efficient electronic transport channels provided by S-scheme heterojunction structure.The density functional theory(DFT)calculation proved that the difference of work function resulted in band bending and forming built-in electric field on the contact interface of PANI/CZS,which facilitated the migration and separation of interfacial photogener-ated charge carriers for the strengthened photocatalytic performance.Further,the degradation interme-diate products and pathways of TCH were also put forwarded in depth based on MS experiment.At last,the S-scheme electron transport model and the photocatalytic reaction mechanism in PANI/CZS hetero-junction structure were studied.This work provided an innovative vision in developing high-performance S-scheme heterojunction multifunctional photocatalysts.
基金supported by the Natural Science Foundation of Jilin Province,China(No.YDZJ202101ZYTS067)the Foundation of Xinzhou Normal University,China(No.2021KY01).
文摘In recent years,many effective photocatalysts have been developed to solve the problem of environmental pollution and clean energy shortage.In this paper,non-noble metal cocatalyst Ni_(3)N nanoparticles supported Zn_(0.5)Cd_(0.5)S(ZCS)nanorods(Ni_(3)N/ZCS)composites were successfully synthesized by ultrasonic method.The hydrogen production efficiencies of the photocatalysts were tested under visible light,which was found that when the loading of Ni_(3)N was 2%of the mass of ZCS,and the Ni_(3)N/ZCS composite had the best hydrogen evolution performance,which could reach 70.3 mmol·h^(-1)·g^(-1).In addition,the quantum efficiency under 420 nm monochromatic light irradiation was 27.2%.Through different characterization analyses,such as X-ray diffraction(XRD),scanning electron microscopy(SEM),and UV-Vis diffuse reflectance spectra(DRS),a possible photocatalytic mechanism was proposed,providing some reference values for non-precious metals as cocatalysts.
基金support from the National Natural Science Foundation of China(Nos.51802170,51772162,and 21801150)the Natural Science Foundation of Shandong Province(Nos.ZR2019MB001,ZR2018BEM014,and ZR2019JQ14)+3 种基金the Youth Innovation and Technology Foundation of Shandong Higher Education Institutions,China(No.2019KJC004)the Taishan Scholar Project of Shandong Province(No.ts201712047)the Special Fund Project to Guide Development of Local Science and Technology by Central Government,the Open Research Fund of State Key Laboratory of Inorganic Synthesis and Preparative Chemistry of Jilin University(No.2019-22)the Taishan Scholar Program of Advantage and Characteristic Discipline Team of Eco-Chemical Process and Technology.
文摘Photocatalytic water splitting for hydrogen(H_(2))production is a green sustainable technology,in which highly-efficient steady photocatalysts are fundamentally required.In this work,unique CdS/Cd_(0.5)Zn_(0.5)S-M0_(1-x)W_(x)S_(2) photocatalyst constructed by CdS hollow nano-spheres with successively surface-modified Cd_(0.5)Zn_(0.5)S shell and defect-rich MO_(1-x)W_(x)S_(2) ultrathin nanosheets was reported for the first time.Interestingly,the Cd_(0.5)Zn_(0.5)S shell could greatly enhance the photo-stability and reduce the carrier recombination of CdS.Meanwhile,enriching active sites and accelerating charge transfer could be achieved via anchoring defect-rich Mo_(1-x)W_(x)S_(2) onto CdS/Cd_(0.5)Zn_(0.5)S hollow heterostructures.Specifically,the optimized CdS/Cd_(0.5)Zn_(0.5)S-Mo_(1-x)W_(x)Sa(6 h Cd_(0.5)Zn_(0.5)S-coating,7 wt.%Mo_(1-x)W_(x)S_(2),x=0.5)hybrid delivered an exceptional H_(2) generation rate of 215.99 mmol·g^(-1)·h^(-1),which is approximately 502,134,and 23 times that of pure CdS,CdS/Cd_(0.5)Zn_(0.5)S,and 3 wt.%Pt-loaded CdS/Cd_(0.5)Zn_(0.5)S,respectively.Remarkably,a high H_(2) evolution reaction(HER)apparent quantum yield(AQY)of 64.81%was obtained under 420-nm irradiation.In addition,the CdS/Cd_(0.5)Zn_(0.5)S-Mo_(1-x)W_(x)S_(2) was also durable for H2 production under long-term irradiation.This work provides valuable inspirations to rational design and synthesis of efficient and stable hybrid photocatalysts for solar energy conversion.
