In this study,an acid-induced assembly strategy for a rutile TiO2 photocatalyst was proposed on the basis of the treatment of lamellar protonated titanate with a concentrated HNO3 solution.Nitrate groups were successf...In this study,an acid-induced assembly strategy for a rutile TiO2 photocatalyst was proposed on the basis of the treatment of lamellar protonated titanate with a concentrated HNO3 solution.Nitrate groups were successfully grafted onto a TiO2 surface and induced the assembly of rutile TiO2 nanorods into uniform spindle-like nanobundles.The resulting TiO2 product achieved a photocatalytic hydrogen evolution rate of 402.4μmol h^?1,which is 3.1 times higher than that of Degussa P25-TiO2.It was demonstrated that nitrate group grafting caused the rutile TiO2 surface to become negatively charged,which is favorable for trapping positive protons and improving charge carrier separation,thereby enhancing photocatalytic hydrogen production.Additionally,surface charges were crucial to structural stability based on electrostatic repulsion.This study not only developed a facile surface modification strategy for fabricating efficient H2 production photocatalysts but also identified an influence mechanism of inorganic acids different from that reported in the literature.展开更多
Fuel cells have attracted extensive attention due to their high conversion efficiency and environmental friendliness.However,their wider application is limited by the poor activity and high cost of platinum(Pt),which ...Fuel cells have attracted extensive attention due to their high conversion efficiency and environmental friendliness.However,their wider application is limited by the poor activity and high cost of platinum(Pt),which is widely used as the cathode catalyst to overcome the slow kinetics associated with oxygen reduction reaction(ORR).Pt‐based composites with one‐dimensional(1D)nanoarchitectures demonstrate great advantages towards efficient ORR catalysis.This review focuses on the recent advancements in the design and synthesis of 1D Pt‐based ORR catalysts.After introducing the fundamental ORR mechanism and the advanced 1D architectures,their synthesis strategies(template‐based and template‐free methods)are discoursed.Subsequently,their morphology and structure optimization are highlighted,followed by the superstructure assembly using 1D Pt‐based blocks.Finally,the challenges and perspectives on the synthesis innovation,structure design,physical characterization,and theoretical investigations are proposed for 1D Pt‐based ORR nanocatalysts.We anticipate this study will inspire more research endeavors on efficient ORR nanocatalysts in fuel cell application.展开更多
The search for active,stable,and cost-effective electrocatalysts for hydrogen evolution reaction(HER)is desirable,but it remains a great challenge in the overall water splitting.Here,we report the synthesis of nickel ...The search for active,stable,and cost-effective electrocatalysts for hydrogen evolution reaction(HER)is desirable,but it remains a great challenge in the overall water splitting.Here,we report the synthesis of nickel boron nanoparticles supported on Vulcan carbon(Ni-B)via a simple,yet scalable,two-step chemical reduction–annealing strategy.The results of the electrochemical measurements suggest that the overpotentials of Ni-B-400 are 114 and 215 mV(in 1 mol L^–1 KOH)at current densities of 10 and 40 mA cm^?2,respectively,indicating an exceedingly good electrocatalytic activity in the HER.More importantly,Ni-B maintains a current density of 7.6 mA cm^-2 at an overpotential of 0.15 V for 20 h in the durability test.The excellent HER activity of Ni-B-400 is derived from the small particle size and the expanded lattice of Ni,which can optimize the hydrogen absorption energy and enhance the electrocatalytic properties.展开更多
基金financially supported by the National Natural Science Foundation of China (No. 21805104, No. 21802048)the Fundamental Research Funds for the Central Universities (No. 2018KFYXKJC044, No. 2018KFYYXJJ121)the National 1000 Young Talents Program of China
基金supported by the National Natural Science Foundation of China (21771070, 21571071)the Fundamental Research Funds for the Central Universities (2018KFYYXJJ120, 2019KFYRCPY104)~~
文摘In this study,an acid-induced assembly strategy for a rutile TiO2 photocatalyst was proposed on the basis of the treatment of lamellar protonated titanate with a concentrated HNO3 solution.Nitrate groups were successfully grafted onto a TiO2 surface and induced the assembly of rutile TiO2 nanorods into uniform spindle-like nanobundles.The resulting TiO2 product achieved a photocatalytic hydrogen evolution rate of 402.4μmol h^?1,which is 3.1 times higher than that of Degussa P25-TiO2.It was demonstrated that nitrate group grafting caused the rutile TiO2 surface to become negatively charged,which is favorable for trapping positive protons and improving charge carrier separation,thereby enhancing photocatalytic hydrogen production.Additionally,surface charges were crucial to structural stability based on electrostatic repulsion.This study not only developed a facile surface modification strategy for fabricating efficient H2 production photocatalysts but also identified an influence mechanism of inorganic acids different from that reported in the literature.
文摘Fuel cells have attracted extensive attention due to their high conversion efficiency and environmental friendliness.However,their wider application is limited by the poor activity and high cost of platinum(Pt),which is widely used as the cathode catalyst to overcome the slow kinetics associated with oxygen reduction reaction(ORR).Pt‐based composites with one‐dimensional(1D)nanoarchitectures demonstrate great advantages towards efficient ORR catalysis.This review focuses on the recent advancements in the design and synthesis of 1D Pt‐based ORR catalysts.After introducing the fundamental ORR mechanism and the advanced 1D architectures,their synthesis strategies(template‐based and template‐free methods)are discoursed.Subsequently,their morphology and structure optimization are highlighted,followed by the superstructure assembly using 1D Pt‐based blocks.Finally,the challenges and perspectives on the synthesis innovation,structure design,physical characterization,and theoretical investigations are proposed for 1D Pt‐based ORR nanocatalysts.We anticipate this study will inspire more research endeavors on efficient ORR nanocatalysts in fuel cell application.
基金supported by the National Natural Science Foundation of China(21573083)the 1000 Young Talent(to Deli Wang)initiatory financial support from Huazhong University of Science and Technology(HUST)~~
文摘The search for active,stable,and cost-effective electrocatalysts for hydrogen evolution reaction(HER)is desirable,but it remains a great challenge in the overall water splitting.Here,we report the synthesis of nickel boron nanoparticles supported on Vulcan carbon(Ni-B)via a simple,yet scalable,two-step chemical reduction–annealing strategy.The results of the electrochemical measurements suggest that the overpotentials of Ni-B-400 are 114 and 215 mV(in 1 mol L^–1 KOH)at current densities of 10 and 40 mA cm^?2,respectively,indicating an exceedingly good electrocatalytic activity in the HER.More importantly,Ni-B maintains a current density of 7.6 mA cm^-2 at an overpotential of 0.15 V for 20 h in the durability test.The excellent HER activity of Ni-B-400 is derived from the small particle size and the expanded lattice of Ni,which can optimize the hydrogen absorption energy and enhance the electrocatalytic properties.
