Metal doped cobalt-based spinel type catalysts prepared by co-precipitation route are considered as suitable candidates for OER, ORR, metal air batteries, fuel cells, detoxification of water, etc. For the purpose, metal doped oxides with formula MCo2O4 (M= Mg, Al and Fe) have been prepared by thermal decomposition of their metal carbonate precipitates and characterized by IR, XRD, CV, EIS and Tafel polarization techniques. The FTIR spectra of oxides show absorption bands ~ 650 cm-1 and ~ 560 cm-1 for respective stretching and bending modes of vibration of Co-O bond at octahedral sites and formation of nano-size (~ 18 nm) single phase cubical crystal with spinel geometry is confirmed by powder XRD patterns. The cyclic voltammetric curves of oxide electrodes in 1 M KOH solution showed a redox peak at Eo = 434 -516 mV for Co2+/Co3+ reactions. The electrocatalytic activity of oxide electrodes for oxygen evolution reaction in 1 M KOH at 25 °C was also studied by Tafel polarization technique and polarization curve of each oxides showed two Tafel slopes and order of OER is unity.

中文翻译：

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Mg、Al和Fe掺杂尖晶石氧化物的电催化析氧反应

通过共沉淀途径制备的金属掺杂钴基尖晶石型催化剂被认为是 OER、ORR、金属空气电池、燃料电池、水解毒等的合适候选者。为此目的，金属掺杂氧化物的分子式为 MCo2O4 (M= Mg、Al 和 Fe) 已通过其金属碳酸盐沉淀的热分解制备，并通过 IR、XRD、CV、EIS 和 Tafel 极化技术表征。氧化物的 FTIR 光谱显示吸收带 ~ 650 cm-1 和 ~ 560 cm-1 分别用于八面体位置的 Co-O 键振动的拉伸和弯曲模式以及纳米尺寸 (~ 18 nm) 单相立方晶体的形成具有尖晶石几何形状的粉末 XRD 图案证实了这一点。对于 Co2+/Co3+ 反应，氧化物电极在 1 M KOH 溶液中的循环伏安曲线显示在 Eo = 434 -516 mV 处的氧化还原峰。