Developing efficient water-splitting electrocatalysts, particularly for the anodic oxygen evolution reaction （OER）, is an important challenge in energy conversion technologies. In this study, we report the developme...Developing efficient water-splitting electrocatalysts, particularly for the anodic oxygen evolution reaction （OER）, is an important challenge in energy conversion technologies. In this study, we report the development of iron-doped nickel disulfide nanoarray on Ti mesh （Fe0.1-NiS2 NA/Ti） via the sulfidation of its nickel-iron-layered double hydroxide precursor （NiFe-LDH NAFFi）. As a three-dimensional OER anode, Fe0.1NiS2 NA/Ti exhibits remarkable activity and stability in 1.0 M KOH, with the requirement of a low overpotential of 231 mV to achieve 100 mA·cm^-2. In addition, it exhibits excellent activity and durability in 30 wt.% KOH. Notably, this electrode is also efficient for the cathodic hydrogen evolution reaction under alkaline conditions.展开更多
Designing efficient electrocatalysts for the hydrogen evolution reaction （HER） has attracted substantial attention owing to the urgent demand for clean energy to face the energy crisis and subsequent environmental i...Designing efficient electrocatalysts for the hydrogen evolution reaction （HER） has attracted substantial attention owing to the urgent demand for clean energy to face the energy crisis and subsequent environmental issues in the near future. Among the large variety of HER catalysts, molybdenum disulfide （MoS2） has been regarded as the most famous catalyst owing to its abundance, low price, high efficiency, and definite catalytic mechanism. In this study, defect-engineered MoS2 nanowall （NW） catalysts with controllable thickness were fabricated and exhibited a significantly enhanced HER performance. Benefiting from the highly exposed active edge sites and the rough surface accompanied by the robust NW structure, the defect-rich MoS2 NW catalyst with an optimized thickness showed an ultralow onset overpotential of 85 mV, a high current density of 310.6 mA·cm^-2 at η = 300 mV, and a low potential of 95 mV to drive a 10 mA·cm^-2 cathodic current. Additionally, excellent electrochemical stability was realized, making this freestanding NW catalyst a promising candidate for practical water splitting and hydrogen production.展开更多
文摘设计低廉、高效且长稳定的析氢反应(HER)催化剂对于水分解技术的工业实施至关重要。本研究采用溶胶凝胶法结合后续热分解的方式制备出了异质纳米结构NiO KNbO_(3)催化剂,通过X射线衍射(XRD)、X射线光电子能谱(XPS)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)和电化学工作站(CHI660E)对NiO KNbO_(3)催化剂的晶型结构、元素价态、微观形貌和HER催化性能进行了系统分析。结果表明,NiO KNbO_(3)催化剂在1 mol L KOH电解液中表现出优异的HER催化性能,-10 mA cm 2电流密度下的析氢反应过电位仅为-217 mV,对应Tafel斜率为77.4 mV dec,在24 h恒电位析氢反应稳定性测试中,表现出良好的催化稳定性和耐腐蚀性。NiO KNbO_(3)催化剂优异的HER性能归因于NiO和KNbO_(3)的协同作用以及独特的异质纳米复合结构增大了活性位点暴露和改善了离子传输路径。
基金This work was supported by the National Natural Science Foundation of China （No. 21575137）.
文摘Developing efficient water-splitting electrocatalysts, particularly for the anodic oxygen evolution reaction （OER）, is an important challenge in energy conversion technologies. In this study, we report the development of iron-doped nickel disulfide nanoarray on Ti mesh （Fe0.1-NiS2 NA/Ti） via the sulfidation of its nickel-iron-layered double hydroxide precursor （NiFe-LDH NAFFi）. As a three-dimensional OER anode, Fe0.1NiS2 NA/Ti exhibits remarkable activity and stability in 1.0 M KOH, with the requirement of a low overpotential of 231 mV to achieve 100 mA·cm^-2. In addition, it exhibits excellent activity and durability in 30 wt.% KOH. Notably, this electrode is also efficient for the cathodic hydrogen evolution reaction under alkaline conditions.
基金Acknowledgements This work was financially supported by the National Basic Research Program of China （No. 2015CB932302）, the National Natural Science Foundation of China （Nos. 21501112, 21331005, 21401181, U1532265, U1632149, 91422303, and 11321503）, and Natural Science Foundation of Shandong Province （No. ZR2014BQ007）.
文摘Designing efficient electrocatalysts for the hydrogen evolution reaction （HER） has attracted substantial attention owing to the urgent demand for clean energy to face the energy crisis and subsequent environmental issues in the near future. Among the large variety of HER catalysts, molybdenum disulfide （MoS2） has been regarded as the most famous catalyst owing to its abundance, low price, high efficiency, and definite catalytic mechanism. In this study, defect-engineered MoS2 nanowall （NW） catalysts with controllable thickness were fabricated and exhibited a significantly enhanced HER performance. Benefiting from the highly exposed active edge sites and the rough surface accompanied by the robust NW structure, the defect-rich MoS2 NW catalyst with an optimized thickness showed an ultralow onset overpotential of 85 mV, a high current density of 310.6 mA·cm^-2 at η = 300 mV, and a low potential of 95 mV to drive a 10 mA·cm^-2 cathodic current. Additionally, excellent electrochemical stability was realized, making this freestanding NW catalyst a promising candidate for practical water splitting and hydrogen production.
