Herein, a stable and efficient CoS_(2)-ReS_(2) electrocatalyst is successfully constructed by using the different molar ratios of CoS_(2) on ReS_(2). The size and morphology of the catalysts are significantly changed ...Herein, a stable and efficient CoS_(2)-ReS_(2) electrocatalyst is successfully constructed by using the different molar ratios of CoS_(2) on ReS_(2). The size and morphology of the catalysts are significantly changed after the CoS_(2) is grown on ReS_(2), providing regulation of the catalytic activity of ReS_(2). Particularly, the optimized CoS_(2)-ReS_(2) shows superior electrocatalytic properties with a low voltage of 1.48 V at 20 mA cm^(-2) for overall water splitting in 1.0 M KOH, which is smaller than the noble metal-based catalysts(1.77 V at 20 mA cm^(-2)). The XPS, XAS, and theoretical data confirm that the interfacial regulation of ReS_(2) by CoS_(2) can provide rich edge catalytic sites, which greatly optimizes the catalytic kinetics and drop the energy barrier for oxygen/hydrogen evolution reactions. Our results demonstrated that interfacial engineering is an efficient route for fabricating high-performance water splitting electrocatalysts.展开更多
Rational coupling of hydrogen evolution reaction(HER) and oxygen evolution reaction(OER) catalysts is extremely important for practical overall water splitting,but it is still challenging to construct such bifunctiona...Rational coupling of hydrogen evolution reaction(HER) and oxygen evolution reaction(OER) catalysts is extremely important for practical overall water splitting,but it is still challenging to construct such bifunctional heterostructures.Herein,we present a metal-organic framework(MOF)-etching strategy to design free-standing and hierarchical hollow CoS_(2)-MoS_(2) heteronanosheet arrays for both HER and OER.Resulting from the controllable etching of MOF by MoO_(4)^(2-) and in-situ sulfuration,the obtained CoS_(2)-MoS_(2) possesses abundant heterointerfaces with modulated local charge distribution,which promote water dissociation and rapid electrocatalytic kinetics.Moreover,the two-dimensional hollow array architecture can not only afford rich surface-active sites,but also facilitate the penetration of electrolytes and the release of evolved H_(2)/O_(2) bubbles.Consequently,the engineered CoS_(2)-MoS_(2) heterostructure exhibits small overpotentials of 82 mV for HER and 266 mV for OER at 10 mA cm^(-2).The corresponding alkaline electrolyzer affords a cell voltage of 1.56 V at 10 mA cm^(-2) to boost overall water splitting,along with robust durability over 24 h, even surpassing the benchmark electrode couple composed of IrO_(2) and Pt/C The present work may provide valuable insights for developing MOF-derived heterogeneous electrocatalysts with tailored interface/surface structure for widespread application in catalysis and other energyrelated areas.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
In order to obtain an advanced anode material that exhibits excellent electrochemical performance in sodium ion batteries,a hollow nanocube MnS-CoS_(2)-NC@NC(NC=nitrogen-doped carbon)with two kinds of nitrogen-doped c...In order to obtain an advanced anode material that exhibits excellent electrochemical performance in sodium ion batteries,a hollow nanocube MnS-CoS_(2)-NC@NC(NC=nitrogen-doped carbon)with two kinds of nitrogen-doped carbon was synthesized by simple one-step calcination.One of the two kinds of nitrogen-doped carbon comes from the organic ligands in the precursor being mixed in the sulfide after calcination,and the other comes from the calcination of the coated polydopamine(PDA)to form a carbon shell wrapped outside the sulfide.The characteristic nanostructure with two kinds of nitrogen-doped carbon can not only improve the overall conductivity of the electrode material,which is obviously beneficial to the rapid transmission of sodium ions and thus outstanding rate performance,but also can alleviate volume expansion to maintain battery cycle stability.In the half-cell,the MnS-CoS_(2)-NC@NC electrode not only provides an ultra-high specific capacity of 608.5 mA·h·g^(-1)at 0.2 A·g^(-1)for 100 cycles,but also shows an outstanding rate performance of 560.5 mA·h·g^(-1)at 5.0 A·g^(-1)for 1,100 cycles.Even in a full-cell composed with Na3V2(PO4)3 as the positive material,it can still maintain a capacity of 436.7 mA·h·g^(-1)after 900 cycles at 1.0 A·g^(-1).In order to explore its sodium storage mechanism,in-situ and ex-situ X-ray diffraction(XRD)tests were carried out to prove that CoS_(2)and MnS were reduced to produce metallic Co and metallic Mn during the discharging process,respectively,and reversibly returned during the charging process.展开更多
Metal sulfides have been widely enticed as battery-type electrodes in supercapacitor devices because of their maximal theoretical capacitance.Nevertheless,their lower conductivity and ion transport kinetics can largel...Metal sulfides have been widely enticed as battery-type electrodes in supercapacitor devices because of their maximal theoretical capacitance.Nevertheless,their lower conductivity and ion transport kinetics can largely restrict their rate performance,hence the practical usage in fields of demanding high power devices.Therefore,the design of new electrodes with higher energy and power densities remains a highly challenging task.To the best of our knowledge,a novel hierarchical composite of Al-CoS_(2) on nitrogendoped graphene(NG)is prepared based on a zeolite imidazole framework using a simple and scalable hydrothermal process.In this hybrid,ultrathin Al-CoS_(2) nanosheet arrays are vertically orientated on the NG framework to limit self-aggregation,hence increasing the electrical property and cycle stability of composite.It is investigated that the Al/Co feeding ratio plays a crucial role in controlling the obtained hierarchical structure of Al-Co-S sheets and their electrode performance.Also,Al^(3+) can influence remarkably the morphology and electrochemical property of the resultant graphene composite.An effective synergism is noticed between the redox Al-CoS_(2) and NG resulting in fast electron transfer and chargingdischarging processes.Surprisingly,when the as-developed composite is utilized as a positive electrode at an applied current density of 1 A/g,a specific capacitance of 1915.8 F/g is attained with ultra-long cycle stability(96%,10,000 cycles)and an excellent retention rate(~89%).As a consequence,when a solid-state asymmetric supercapacitor(ASC)device is made by combining an Al-CoS_(2) @NG hybrid with a negative electrode made of polyaniline(PANI)derived carbon nanorods(PCNRs),it demonstrates remarkable specific capacitance(188 F/g),energy density(66.9 Wh/kg),and cyclic stability of 92%after 10,000 cycles.This may open the pathway for the application of the next-generation supercapacitors in the future.展开更多
Metal sulfides have been widely investigated as promising electrode materials for potassium-ion batteries(PIBs)due to their high theoretical capacities.However,the practical application of metal sulfides in PIBs is st...Metal sulfides have been widely investigated as promising electrode materials for potassium-ion batteries(PIBs)due to their high theoretical capacities.However,the practical application of metal sulfides in PIBs is still hindered by their intrinsic shortcomings of low conductivity and severe volume changes during the potassiation/depotassiation process.Herein,a simple template-based two-step annealing strategy is proposed to impregnate CoS_(2) nanoparticles in the well-structured carbon nanocubes(denoted CoS_(2)/CNCs)as an advanced anode material for PIBs.The ex-situ XRD measurements reveal the K+storage mechanism in CoS_(2)/CNCs.Benefiting from the unique structures,including abundant active interfacial sites,high electronic conductivity,and significantly alleviated volume variation,CoS_(2)/CNCs present a high specific capacity(537.3 mAh g^(−1) at 0.1 A g^(−1)),good cycling stability(322.4 mAh g^(−1) at 0.5 A g^(−1) after 300 cycles),and excellent rate capability(153.1 mAh g^(−1) at 5 A g^(−1)).Moreover,the obtained nanocomposite shows superior potassium storage properties in K-ion full cells when it is coupled with a KVPO4F cathode.展开更多
Nowadays,two-dimensional transition metal chalcogenides have become attractive materials for flexible wearable devices because of their intriguing chemistry characteristics and sensitivity to external stimuli.However,...Nowadays,two-dimensional transition metal chalcogenides have become attractive materials for flexible wearable devices because of their intriguing chemistry characteristics and sensitivity to external stimuli.However,the growth of two-dimensional materials on polymer surfaces is generally carried out by the time-consuming and costly chemical vapor deposition method.Reducing the manufacturing and integration costs while improving the device performance remains to be challenging.Herein,we report a simple liquid metal-assisted hydrothermal method for the growth of two-dimensional nanomaterials on the polymer surface.Specifically,a layer of liquid metal was coated on commercial tape,while layered cobalt sulfide was grown on its surface by a simple one-step hydrothermal method.Different kinds of flexible sensors can be prepared,such as bending sensor,pressure sensor,humidity sensor,which can be used to detect motion,writing,breathing,other signals.This strategy can also be assigned to sensing signals on different objects,which may further expand and enrich the application of twodimensional materials in sensing.展开更多
基金supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT)(NRF-2022R1A2C2093415) and (NRF-2018R1A2B6006721)Institute for Basic Science of Korea (IBS-R011-D1)the Korea Medical Device Development Fund grant funded by the Korean government (the Ministry of Science and ICT, the Ministry of Trade, Industry and Energy, the Ministry of Health & Welfare, the Ministry of Food and Drug Safety) (Project Number: KMDF_PR_20200901_0004)。
文摘Herein, a stable and efficient CoS_(2)-ReS_(2) electrocatalyst is successfully constructed by using the different molar ratios of CoS_(2) on ReS_(2). The size and morphology of the catalysts are significantly changed after the CoS_(2) is grown on ReS_(2), providing regulation of the catalytic activity of ReS_(2). Particularly, the optimized CoS_(2)-ReS_(2) shows superior electrocatalytic properties with a low voltage of 1.48 V at 20 mA cm^(-2) for overall water splitting in 1.0 M KOH, which is smaller than the noble metal-based catalysts(1.77 V at 20 mA cm^(-2)). The XPS, XAS, and theoretical data confirm that the interfacial regulation of ReS_(2) by CoS_(2) can provide rich edge catalytic sites, which greatly optimizes the catalytic kinetics and drop the energy barrier for oxygen/hydrogen evolution reactions. Our results demonstrated that interfacial engineering is an efficient route for fabricating high-performance water splitting electrocatalysts.
基金the financial support by the National Natural Science Foundation of China(NSFC) Grants(51702295)。
文摘Rational coupling of hydrogen evolution reaction(HER) and oxygen evolution reaction(OER) catalysts is extremely important for practical overall water splitting,but it is still challenging to construct such bifunctional heterostructures.Herein,we present a metal-organic framework(MOF)-etching strategy to design free-standing and hierarchical hollow CoS_(2)-MoS_(2) heteronanosheet arrays for both HER and OER.Resulting from the controllable etching of MOF by MoO_(4)^(2-) and in-situ sulfuration,the obtained CoS_(2)-MoS_(2) possesses abundant heterointerfaces with modulated local charge distribution,which promote water dissociation and rapid electrocatalytic kinetics.Moreover,the two-dimensional hollow array architecture can not only afford rich surface-active sites,but also facilitate the penetration of electrolytes and the release of evolved H_(2)/O_(2) bubbles.Consequently,the engineered CoS_(2)-MoS_(2) heterostructure exhibits small overpotentials of 82 mV for HER and 266 mV for OER at 10 mA cm^(-2).The corresponding alkaline electrolyzer affords a cell voltage of 1.56 V at 10 mA cm^(-2) to boost overall water splitting,along with robust durability over 24 h, even surpassing the benchmark electrode couple composed of IrO_(2) and Pt/C The present work may provide valuable insights for developing MOF-derived heterogeneous electrocatalysts with tailored interface/surface structure for widespread application in catalysis and other energyrelated areas.
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.
文摘In order to obtain an advanced anode material that exhibits excellent electrochemical performance in sodium ion batteries,a hollow nanocube MnS-CoS_(2)-NC@NC(NC=nitrogen-doped carbon)with two kinds of nitrogen-doped carbon was synthesized by simple one-step calcination.One of the two kinds of nitrogen-doped carbon comes from the organic ligands in the precursor being mixed in the sulfide after calcination,and the other comes from the calcination of the coated polydopamine(PDA)to form a carbon shell wrapped outside the sulfide.The characteristic nanostructure with two kinds of nitrogen-doped carbon can not only improve the overall conductivity of the electrode material,which is obviously beneficial to the rapid transmission of sodium ions and thus outstanding rate performance,but also can alleviate volume expansion to maintain battery cycle stability.In the half-cell,the MnS-CoS_(2)-NC@NC electrode not only provides an ultra-high specific capacity of 608.5 mA·h·g^(-1)at 0.2 A·g^(-1)for 100 cycles,but also shows an outstanding rate performance of 560.5 mA·h·g^(-1)at 5.0 A·g^(-1)for 1,100 cycles.Even in a full-cell composed with Na3V2(PO4)3 as the positive material,it can still maintain a capacity of 436.7 mA·h·g^(-1)after 900 cycles at 1.0 A·g^(-1).In order to explore its sodium storage mechanism,in-situ and ex-situ X-ray diffraction(XRD)tests were carried out to prove that CoS_(2)and MnS were reduced to produce metallic Co and metallic Mn during the discharging process,respectively,and reversibly returned during the charging process.
基金supported by the National Research Foundation of Korea(NRF)funded by the Ministry of Education(NRF-2019R1l1A3A010638331,NRF-2021R1I1A1A01059870 and NRF-2022R1I1A1A01069960)the Hannam University research fund in 2022+4 种基金the Marie Sklodowska-Curie grant agreement(801538)the CONEX-Plus program at the Universidad CarlosⅢde Madridthe European Union’s Horizon 2020 research and innovation programmeAbdolkhaled Mohammadi(Universitéde Montpellier,France)Pranay Barkataki(Sony R&D,India)for fruitful discussion and support。
文摘Metal sulfides have been widely enticed as battery-type electrodes in supercapacitor devices because of their maximal theoretical capacitance.Nevertheless,their lower conductivity and ion transport kinetics can largely restrict their rate performance,hence the practical usage in fields of demanding high power devices.Therefore,the design of new electrodes with higher energy and power densities remains a highly challenging task.To the best of our knowledge,a novel hierarchical composite of Al-CoS_(2) on nitrogendoped graphene(NG)is prepared based on a zeolite imidazole framework using a simple and scalable hydrothermal process.In this hybrid,ultrathin Al-CoS_(2) nanosheet arrays are vertically orientated on the NG framework to limit self-aggregation,hence increasing the electrical property and cycle stability of composite.It is investigated that the Al/Co feeding ratio plays a crucial role in controlling the obtained hierarchical structure of Al-Co-S sheets and their electrode performance.Also,Al^(3+) can influence remarkably the morphology and electrochemical property of the resultant graphene composite.An effective synergism is noticed between the redox Al-CoS_(2) and NG resulting in fast electron transfer and chargingdischarging processes.Surprisingly,when the as-developed composite is utilized as a positive electrode at an applied current density of 1 A/g,a specific capacitance of 1915.8 F/g is attained with ultra-long cycle stability(96%,10,000 cycles)and an excellent retention rate(~89%).As a consequence,when a solid-state asymmetric supercapacitor(ASC)device is made by combining an Al-CoS_(2) @NG hybrid with a negative electrode made of polyaniline(PANI)derived carbon nanorods(PCNRs),it demonstrates remarkable specific capacitance(188 F/g),energy density(66.9 Wh/kg),and cyclic stability of 92%after 10,000 cycles.This may open the pathway for the application of the next-generation supercapacitors in the future.
基金This work was supported by the Natural Science Foundation of Jiangsu Province of China(BK20180086).
文摘Metal sulfides have been widely investigated as promising electrode materials for potassium-ion batteries(PIBs)due to their high theoretical capacities.However,the practical application of metal sulfides in PIBs is still hindered by their intrinsic shortcomings of low conductivity and severe volume changes during the potassiation/depotassiation process.Herein,a simple template-based two-step annealing strategy is proposed to impregnate CoS_(2) nanoparticles in the well-structured carbon nanocubes(denoted CoS_(2)/CNCs)as an advanced anode material for PIBs.The ex-situ XRD measurements reveal the K+storage mechanism in CoS_(2)/CNCs.Benefiting from the unique structures,including abundant active interfacial sites,high electronic conductivity,and significantly alleviated volume variation,CoS_(2)/CNCs present a high specific capacity(537.3 mAh g^(−1) at 0.1 A g^(−1)),good cycling stability(322.4 mAh g^(−1) at 0.5 A g^(−1) after 300 cycles),and excellent rate capability(153.1 mAh g^(−1) at 5 A g^(−1)).Moreover,the obtained nanocomposite shows superior potassium storage properties in K-ion full cells when it is coupled with a KVPO4F cathode.
基金the National Natural Science Foundation of China(No.51972064).
文摘Nowadays,two-dimensional transition metal chalcogenides have become attractive materials for flexible wearable devices because of their intriguing chemistry characteristics and sensitivity to external stimuli.However,the growth of two-dimensional materials on polymer surfaces is generally carried out by the time-consuming and costly chemical vapor deposition method.Reducing the manufacturing and integration costs while improving the device performance remains to be challenging.Herein,we report a simple liquid metal-assisted hydrothermal method for the growth of two-dimensional nanomaterials on the polymer surface.Specifically,a layer of liquid metal was coated on commercial tape,while layered cobalt sulfide was grown on its surface by a simple one-step hydrothermal method.Different kinds of flexible sensors can be prepared,such as bending sensor,pressure sensor,humidity sensor,which can be used to detect motion,writing,breathing,other signals.This strategy can also be assigned to sensing signals on different objects,which may further expand and enrich the application of twodimensional materials in sensing.
