新型NiCo₂O₄电极析氧反应机理

来源期刊：中南大学学报(自然科学版)2000年第4期

论文作者：陈建军 杨建红 陈晓春 李庆余 刘业翔 危爱芳 周志强

文章页码：303 - 306

关键词：碱性水;电解;阳极;析氧反应

Key words：alkaline water; electrolysis; anode; oxygen evolution reaction

摘    要：在贱金属铁基上表面化学镀Ni-Co-P,然后通过化学复合镀制得Ni-Co-P-Al₂O₃中间层,复合镀层用5 mol·L^-1NaOH溶液浸出,可制得新型Ni-Co-P微孔活性中间层,在中间层上再涂覆匹配性较好的NiCo₂O₄表面活性层,该活性层是由一定Ni(NO₃)₂和Co(NO₃)₂的量配比通过高温热解而成.为考察该电极在碱性溶液的析氧反应机理,通过恒电位阶跃实验I~t曲线求出了不同时间下的电量Q,由Q对t^1/2作图得Q-t^1/2曲线.结果证明,Q-t^1/2曲线为不通过坐标原点的直线,说明该析氧电极反应为典型的不可逆反应.通过对析氧电极反应假想模型进行动力学推算及实验,初步确定了电极反应的速度控制步骤.

Abstract: ANi-Co-P-Al₂O₃composite coatingwas electrolessly plated after Ni-Co-P coating on Fe matrix. Then composite coatingwas immersed in 5 mol/L NaOH solution to obtain an active Ni-Co-P coating (middle coating) with microholes,on which an active surface coating of NiCo₂O₄ was pyrolysisly formed by dipping in 2.0 mol/LNi(NO₃)₂, Co(NO₃)₂ several times. The electric charge(Q) was measured by I-tcurves obtained through potentiostatic step at different time,Q-t^1/2 curvewas a straight line not through the origin dot, demonstratingoxygen evolution reaction was typically irreversible. The step of rate controlling of the electrode reaction in different current density was determined according to the electrode reaction dynamics and experiment results.