The development of efficient and stable electrocatalysts for the oxygen evolution reaction(OER),which is critical for the development of water splitting,has attracted great interest from many researchers.However,there...The development of efficient and stable electrocatalysts for the oxygen evolution reaction(OER),which is critical for the development of water splitting,has attracted great interest from many researchers.However,there have been few reports exhibiting satisfactory activity and durability under high current density(up to 1000 mA cm^(−2)),which are significant for the practical production of water splitting.Herein,a novel electrocatalyst,CuS-Ni_(3)S_(2),in situ grown from porous CuNi alloy supported on nickel foam(CuS-Ni_(3)S_(2)/CuNi/NF)was obtained via a facile two-step method,and it has achieved excellent OER performance in alkaline solution even under high current density.The electrocatalyst only needed low overpotentials of 337,444 and 510 mV to reach the very high current densities of 100,500,and 1000 mA cm^(−2),respectively,and it presented excellent durability at a relatively high current density of 100 mA cm^(−2)for 15 h.Despite the current density being normalized by the catalytic electrode’s geometrical area,both the mass activity and turnover frequency(TOF)for each active site showed the superior catalytic activity of CuS-Ni_(3)S_(2)/CuNi/NF.With the assistance of theoretical calculations,the participation of CuS was demonstrated to contribute to the excellent OER performance,providing a promising composition for designing and synthesizing novel OER catalysts.展开更多
Developing highly efficient,Earth-abundant,and long-term stable electrocatalysts for the oxygen evolution reaction (OER) is of great importance for realizing industrial hydrogen generation from water splitting.Herein,...Developing highly efficient,Earth-abundant,and long-term stable electrocatalysts for the oxygen evolution reaction (OER) is of great importance for realizing industrial hydrogen generation from water splitting.Herein,a series of novel Fe and Nb co-doped β-Ni(OH)_(2)nanosheet arrays were successfully grown in situ on Ni foam via a chlorine etching method.The representative NiFe_(3)Nb_(2)-OH displayed outstanding OER performance with an overpotential of 294 mV to deliver 100 mA cm^(-2) in an alkaline electrolyte,outperforming other Ni related electrocatalysts.NiFe_(3)Nb_(2)-OH exhibited a stability of 90 h without obvious potential change at 50 mA cm^(-2).Significantly,the doped Fe and Nb effectively enhanced the electrochemical active area and electronic transfer capability of β-Ni(OH)_(2).Density functional theory (DFT) calculations indicated that the Gibbs free energy of the OER intermediates on the Fe,Nb co-doped β-Ni(OH)_(2)electrode was optimized.The tuned electronic interactions between Fe,Nb and Ni apparently boosted the OER performance of NiFe_(3)Nb_(2)-OH.These results demonstrated that Fe and Nb co-doped β-Ni(OH)_(2)is a highly efficient OER electrocatalyst in alkaline media.展开更多
基金the talents start scientific research funds of China University of Petroleum,Beijing(No.2462016YJRC022).
文摘The development of efficient and stable electrocatalysts for the oxygen evolution reaction(OER),which is critical for the development of water splitting,has attracted great interest from many researchers.However,there have been few reports exhibiting satisfactory activity and durability under high current density(up to 1000 mA cm^(−2)),which are significant for the practical production of water splitting.Herein,a novel electrocatalyst,CuS-Ni_(3)S_(2),in situ grown from porous CuNi alloy supported on nickel foam(CuS-Ni_(3)S_(2)/CuNi/NF)was obtained via a facile two-step method,and it has achieved excellent OER performance in alkaline solution even under high current density.The electrocatalyst only needed low overpotentials of 337,444 and 510 mV to reach the very high current densities of 100,500,and 1000 mA cm^(−2),respectively,and it presented excellent durability at a relatively high current density of 100 mA cm^(−2)for 15 h.Despite the current density being normalized by the catalytic electrode’s geometrical area,both the mass activity and turnover frequency(TOF)for each active site showed the superior catalytic activity of CuS-Ni_(3)S_(2)/CuNi/NF.With the assistance of theoretical calculations,the participation of CuS was demonstrated to contribute to the excellent OER performance,providing a promising composition for designing and synthesizing novel OER catalysts.
基金supported by the Natural Science Foundation of China(No.21776248 and 21676246)the Zhejiang Provincial Natural Science Foundation of China(No.LR17B060003)supported by the Fundamental Research Funds for the Central Universities.
文摘Developing highly efficient,Earth-abundant,and long-term stable electrocatalysts for the oxygen evolution reaction (OER) is of great importance for realizing industrial hydrogen generation from water splitting.Herein,a series of novel Fe and Nb co-doped β-Ni(OH)_(2)nanosheet arrays were successfully grown in situ on Ni foam via a chlorine etching method.The representative NiFe_(3)Nb_(2)-OH displayed outstanding OER performance with an overpotential of 294 mV to deliver 100 mA cm^(-2) in an alkaline electrolyte,outperforming other Ni related electrocatalysts.NiFe_(3)Nb_(2)-OH exhibited a stability of 90 h without obvious potential change at 50 mA cm^(-2).Significantly,the doped Fe and Nb effectively enhanced the electrochemical active area and electronic transfer capability of β-Ni(OH)_(2).Density functional theory (DFT) calculations indicated that the Gibbs free energy of the OER intermediates on the Fe,Nb co-doped β-Ni(OH)_(2)electrode was optimized.The tuned electronic interactions between Fe,Nb and Ni apparently boosted the OER performance of NiFe_(3)Nb_(2)-OH.These results demonstrated that Fe and Nb co-doped β-Ni(OH)_(2)is a highly efficient OER electrocatalyst in alkaline media.
