A dual-doping strategy of LaCoO3 for optimized oxygen evolution reaction toward zinc-air batteries application

Abstract

Perovskite-based electrocatalysts are extensively investigated as a replacement for noble metals electrocatalysts for energy storage and conversion devices. Their interesting catalytic activity, low cost, and diversity are considered major advantages. In this work, a facile dual-doping strategy has been conducted and yielded an astonishing upgrade of lanthanum cobaltite; fine-tuning of both A and B sites with calcium and manganese has proven remarkably beneficial. The dual-doping modulates the electronic configuration of both transition metals and raises the oxygen vacancies. Consequently, oxygen evolution reaction has been assessed and La0.8Ca0.2Mn0.2Co0.8O3 showed significantly improved overpotential and maximal current density in comparison with pristine LaCoO3. Furthermore, the ZAB exhibited a high open circuit potential and superior charge-discharge cyclability, compared to Pt/C-based electrodes. The current work explores the influence of simultaneous doping of the A and B sites in lanthanum perovskite oxides on electrocatalytic performance to encourage further exploration of such an approach in electrocatalysis. Novelty statement Simultaneous Ca and Mn dual-doping of LaCoO3 in the A and B sites were successfully applied. The effects on the crystal structure, oxidation states, and electrocatalytic activity were studied. LCMC8228-based ZAB has achieved a large discharge capacity of 88.1 mAh in comparison to the benchmark.