Co_(2)Ni_(1)O_(4)/不锈钢复合材料的制备及其电催化析氧性能

Synthesis and electrocatalytic oxygen evolution performances of Co_(2)Ni_(1)O_(4)/stainless steel composites

电解水包括析氢反应(HER)与析氧反应(OER),由于OER是复杂的4电子转移过程,制作出具有优异耐久性的高活性的非贵金属OER电催化剂对于电解水至关重要。为了降低成本,选择304型不锈钢网(SS)作为基体,使用电沉积的方法制备钴-镍双氢氧化物,利用真空煅烧的方法制备钴-镍氧化物。使用XRD、SEM、TEM、XPS和电化学工作站对Co_(2)Ni_(1)O_(4)/SS复合材料的晶体结构、形貌和电催化OER性能进行了研究。结果表明:电沉积制备的钴-镍双氢氧化物煅烧之后转变成尖晶石结构的钴-镍氧化物;在不锈钢表面成功合成了大量密集的层状结构;在1.0 mol/L KOH电解液中,Co_(2)Ni_(1)O_(4)/SS电极表现出优异的OER电催化性能,达到10 mA·cm^(−2)电流密度时所需要的过电位仅为240 mV,Tafel斜率为53.92 mV·dec^(−1),并且表现出优异的稳定性。

Electrolytic water includes hydrogen evolution reaction(HER)and oxygen evolution reaction(OER),because OER is a complex 4-electron transfer process,developing highly active non-precious OER electrocatalysts with superior durability is crucial to electrolytic water.In order to reduce the cost,304 stainless steel mesh(SS)was selected as the matrix,Co-Ni double hydroxides was prepared by electrodeposition,Co-Ni oxides were produced by vacuum calcination.The crystal structure,morphology and electrocatalytic OER performance of Co_(2)Ni_(1)O_(4)/SS composite were studied by XRD,SEM,TEM,XPS and electrochemical workstation.As a result,the Co-Ni double hydroxides prepared by electrodeposition are transformed into Co-Ni oxides with spinel structure after vacuum calcination;successfully synthesized a large number of dense layered structures on the surface of stainless steel;the Co_(2)Ni_(1)O_(4)/SS electrode exhibits an outstanding OER catalytic activity with an overpotentials of 240 mV at 10 mA·cm^(-2) and a Tafel slop as low as 53.92 mV·dec^(−1) in 1.0 mol/L KOH.In addition,the Co_(2)Ni_(1)O_(4)/SS composites shows excellent stability in the alkaline electrolyte.