The synergistic interaction between metal-organic frameworks(MOFs)and transition metal sulfides(TMS)has been a research hotspot in the field of electrocatalytic water splitting.Herein,nickel sulfide quantum dots@NiFe-...The synergistic interaction between metal-organic frameworks(MOFs)and transition metal sulfides(TMS)has been a research hotspot in the field of electrocatalytic water splitting.Herein,nickel sulfide quantum dots@NiFe-terephthalic acid nanosheet(NSQDs@NiFe-TPA)composites were prepared by a two-step hydrothermal method.The size and crystal structure of nickel sulfides were easily modulated by adjusting the concentration of the sulfurizing agent.The in situ formed NiS/Ni_(3)S_(2)quantum dots with grain sizes of around 5 nm were evenly dispersed on the surface of NiFe-TPA nanosheets,and the overpotential was only 219 mV at 10 mA cm^(-2),and 90%current density could be maintained at 1.5 V(vs.RHE)for 60 h.When the concentration of the sulfurizing agent was increased up to 0.15 mmol L^(-1),the as-prepared Ni_(3)S_(2)@NiFe-TPA exhibited an excellent HER performance.The overpotential is only 109 mV to reach a current density of 10 mA cm^(-2),and it was attenuated by 20 mV after a 60 h stability test at a current density of 20 mA cm^(-2).Furthermore,the overall water-splitting electrolyzer assembled with NSQDs@NiFe-TPA and Ni_(3)S_(2)@NiFe-TPA as anodic and cathodic electrodes exhibited a low cell voltage of 1.66 V at a current density 10 mA cm^(-2),and almost no attenuation was observed after a 60 h stability test.The outstanding electrocatalytic properties of the as-prepared catalyst are due to the synergy of nickel sulfides and 2D MOFs that offers abundant accessible active sites,rapid ion/electron transportation,and convenient O_(2)/H_(2)release channels.展开更多
基金financially supported by the National Key R&D Program of China(Project No.2021YFE0104700)the Science and Technology Development Fund of Egypt(Project No.43149)。
文摘The synergistic interaction between metal-organic frameworks(MOFs)and transition metal sulfides(TMS)has been a research hotspot in the field of electrocatalytic water splitting.Herein,nickel sulfide quantum dots@NiFe-terephthalic acid nanosheet(NSQDs@NiFe-TPA)composites were prepared by a two-step hydrothermal method.The size and crystal structure of nickel sulfides were easily modulated by adjusting the concentration of the sulfurizing agent.The in situ formed NiS/Ni_(3)S_(2)quantum dots with grain sizes of around 5 nm were evenly dispersed on the surface of NiFe-TPA nanosheets,and the overpotential was only 219 mV at 10 mA cm^(-2),and 90%current density could be maintained at 1.5 V(vs.RHE)for 60 h.When the concentration of the sulfurizing agent was increased up to 0.15 mmol L^(-1),the as-prepared Ni_(3)S_(2)@NiFe-TPA exhibited an excellent HER performance.The overpotential is only 109 mV to reach a current density of 10 mA cm^(-2),and it was attenuated by 20 mV after a 60 h stability test at a current density of 20 mA cm^(-2).Furthermore,the overall water-splitting electrolyzer assembled with NSQDs@NiFe-TPA and Ni_(3)S_(2)@NiFe-TPA as anodic and cathodic electrodes exhibited a low cell voltage of 1.66 V at a current density 10 mA cm^(-2),and almost no attenuation was observed after a 60 h stability test.The outstanding electrocatalytic properties of the as-prepared catalyst are due to the synergy of nickel sulfides and 2D MOFs that offers abundant accessible active sites,rapid ion/electron transportation,and convenient O_(2)/H_(2)release channels.
