Surface area,pore properties,synergistic behavior,homogenous dispersion,and interactions between carbon matrix and metal-nanostructures are the key factors for achieving the better performance of carbon-metal based(el...Surface area,pore properties,synergistic behavior,homogenous dispersion,and interactions between carbon matrix and metal-nanostructures are the key factors for achieving the better performance of carbon-metal based(electro)catalysts.However,the traditional hydro-or solvothermal preparation of(electro)catalysts,particularly,bi-or tri-metallic nanostructures anchored graphene(G)or carbon nanotubes(CNTs),often pose to poor metal–support interaction,low synergism,and patchy dispersion.At first,bimetallic flower-like-CuFeS_(2)/NG and cube-like-NiFeS_(2)/NCNTs nanocomposites were prepared by solvothermal method.The resultant bimetallic nanocomposites were employed to derive the 2D-nano-sandwiched Fe_(2)CuNiS_(4)/NGCNTs-SW(electro)catalyst by a very simple and green urea-mediated“mix-heat”method.The desired physicochemical properties of Fe_(2)CuNiS_(4)/NGCNTs-SW such as multiple active sites,strong metal-support interaction,homogenous dispersion and enhanced surface area were confirmed by various microscopic and spectroscopic techniques.To the best of our knowledge,this is the first urea-mediated“mix-heat”method for preparing 2D-nano-sandwiched carbon-metal-based(electro)catalysts.The Fe_(2)CuNiS_(4)/NGCNTs-SW was found to be highly effective for alkaline-mediated oxygen evolution reaction at low onset potential of 284.24 mV,and the stable current density of 10 mA cm^(−2) in 1.0 m KOH for 10 h.Further,the Fe_(2)CuNiS_(4)/NGCNTs-SW demonstrated excellent catalytic activity in the reduction of 4-nitrophenol with good kapp value of 87.71×10^(−2)s^(-1)and excellent reusability over five cycles.Overall,the developed urea-mediated“mix-heat”method is highly efficient for the preparation of metal-nanoarchitectures anchored 2D-nano-sandwiched(electro)catalysts with high synergism,uniform dispersion and excellent metal-support interaction.展开更多
We reports an efficient approach for production of hydrogen from crude bio-oil and biomass char in the dual fixed-bed system by using the electrochemical catalytic reforming method. The maximal absolute hydrogen yield...We reports an efficient approach for production of hydrogen from crude bio-oil and biomass char in the dual fixed-bed system by using the electrochemical catalytic reforming method. The maximal absolute hydrogen yield reached 110.9 g H2/kg dry biomass. The product gas was a mixed gas containing 72%H2, 26%CO2, 1.9%CO, and a trace amount of CH4. It was observed that adding biomass char (a by-product of pyrolysis of biomass) could remarkably increase the absolute H2 yield (about 20%-50%). The higher reforming temperature could enhance the steam reforming reaction of organic compounds in crude bio-oil and the reaction of CO and H20. In addition, the CuZn-Al2O3 catalyst in the water-gas shift bed could also increase the absolute H2 yield via shifting CO to CO2.展开更多
Interface engineering has been widely investigated to regulate the structure and performance of electrodes and photoelectrodes,but the investigation of multiple carbon interface modifications on the electrocatalytic o...Interface engineering has been widely investigated to regulate the structure and performance of electrodes and photoelectrodes,but the investigation of multiple carbon interface modifications on the electrocatalytic oxygen evolution reaction(OER)is still shortage.Herein,we report remarkable promotion of OER performance on the NiFe‐based nanocomposite electrocatalyst via the synergy of multiple carbon‐based interface engineering.Specifically,carbon nanotubes were in situ grown on carbon fiber paper to improve the interface between CFP and NiFeO_(x)H_(y),and graphite carbon nanoparticles were in situ loaded and partly doped into the NiFeO_(x)H_(y) to modify the intergranular interface charge transfer and electronic structure of NiFeO_(x)H_(y).Consequently,the as‐obtained NiFeO_(x)H_(y)‐C/CNTs/CFP catalyst exhibited significantly enhanced electrocatalytic OER activity with an overpotential of 202 mV at 10 mA cm^(-2) in 1 mol L^(-1) KOH.Our work not only extends application of carbon materials but also provides an alternative strategy to develop highly efficient electrocatalysts.展开更多
基金supported by JSPS KAKENHI(Grant number 24K15389)S.C.Kim greatly acknowledges the Basic Science Research Program through the National Research Foundation of Korea(NRF)funded by the Ministry of Education of the Republic of Korea(2020R1I1A3052258)for financial support.
文摘Surface area,pore properties,synergistic behavior,homogenous dispersion,and interactions between carbon matrix and metal-nanostructures are the key factors for achieving the better performance of carbon-metal based(electro)catalysts.However,the traditional hydro-or solvothermal preparation of(electro)catalysts,particularly,bi-or tri-metallic nanostructures anchored graphene(G)or carbon nanotubes(CNTs),often pose to poor metal–support interaction,low synergism,and patchy dispersion.At first,bimetallic flower-like-CuFeS_(2)/NG and cube-like-NiFeS_(2)/NCNTs nanocomposites were prepared by solvothermal method.The resultant bimetallic nanocomposites were employed to derive the 2D-nano-sandwiched Fe_(2)CuNiS_(4)/NGCNTs-SW(electro)catalyst by a very simple and green urea-mediated“mix-heat”method.The desired physicochemical properties of Fe_(2)CuNiS_(4)/NGCNTs-SW such as multiple active sites,strong metal-support interaction,homogenous dispersion and enhanced surface area were confirmed by various microscopic and spectroscopic techniques.To the best of our knowledge,this is the first urea-mediated“mix-heat”method for preparing 2D-nano-sandwiched carbon-metal-based(electro)catalysts.The Fe_(2)CuNiS_(4)/NGCNTs-SW was found to be highly effective for alkaline-mediated oxygen evolution reaction at low onset potential of 284.24 mV,and the stable current density of 10 mA cm^(−2) in 1.0 m KOH for 10 h.Further,the Fe_(2)CuNiS_(4)/NGCNTs-SW demonstrated excellent catalytic activity in the reduction of 4-nitrophenol with good kapp value of 87.71×10^(−2)s^(-1)and excellent reusability over five cycles.Overall,the developed urea-mediated“mix-heat”method is highly efficient for the preparation of metal-nanoarchitectures anchored 2D-nano-sandwiched(electro)catalysts with high synergism,uniform dispersion and excellent metal-support interaction.
基金This work was supported by the National Basic Research Program of Ministry of Science and Technology of China (No.2007CB210206), the National High Tech Research and Development Program (No.2009AA05Z435), and the National Natural Science Foundation of China (No.50772107).
文摘We reports an efficient approach for production of hydrogen from crude bio-oil and biomass char in the dual fixed-bed system by using the electrochemical catalytic reforming method. The maximal absolute hydrogen yield reached 110.9 g H2/kg dry biomass. The product gas was a mixed gas containing 72%H2, 26%CO2, 1.9%CO, and a trace amount of CH4. It was observed that adding biomass char (a by-product of pyrolysis of biomass) could remarkably increase the absolute H2 yield (about 20%-50%). The higher reforming temperature could enhance the steam reforming reaction of organic compounds in crude bio-oil and the reaction of CO and H20. In addition, the CuZn-Al2O3 catalyst in the water-gas shift bed could also increase the absolute H2 yield via shifting CO to CO2.
文摘Interface engineering has been widely investigated to regulate the structure and performance of electrodes and photoelectrodes,but the investigation of multiple carbon interface modifications on the electrocatalytic oxygen evolution reaction(OER)is still shortage.Herein,we report remarkable promotion of OER performance on the NiFe‐based nanocomposite electrocatalyst via the synergy of multiple carbon‐based interface engineering.Specifically,carbon nanotubes were in situ grown on carbon fiber paper to improve the interface between CFP and NiFeO_(x)H_(y),and graphite carbon nanoparticles were in situ loaded and partly doped into the NiFeO_(x)H_(y) to modify the intergranular interface charge transfer and electronic structure of NiFeO_(x)H_(y).Consequently,the as‐obtained NiFeO_(x)H_(y)‐C/CNTs/CFP catalyst exhibited significantly enhanced electrocatalytic OER activity with an overpotential of 202 mV at 10 mA cm^(-2) in 1 mol L^(-1) KOH.Our work not only extends application of carbon materials but also provides an alternative strategy to develop highly efficient electrocatalysts.