Enhancing bifunctional electrocatalysts of hollow Co3O4 nanorods with oxygen vacancies towards ORR and OER for Li-O2 batteries

The Co3O4, which is on the top of volcano plot, having high oxygen vacancy of ca. 30% finely tuned promotes narrow band gap, resulting in the facilitation of the electron and charge transportation. The as-synthesized Co3O4 catalyst can improve the electrocatalytic activity towards oxygen evolution reaction (OER) and oxygen reduction reaction (ORR). The as-prepared catalyst exhibits the superior ORR/OER stability for which the relative current decays only 7% and 14% for OER and ORR, respectively. By contrast, the OER stability of the RuO2 catalyst presents the significant decay in relative current about 20%. The ORR stability of Pt/C also remarkably decreases to 29%. The catalyst here can be used as an efficient bifunctional catalyst at the cathode of Li-O-2 battery. It provides the superior performance as compared to that using the state-of-the-art Pt/C and RuO2/C electrocatalysts. (C) 2020 Published by Elsevier Ltd.

Automated summary

The Co3O4 catalyst with high oxygen vacancy and narrow band gap promotes superior stability in OER and ORR compared to RuO2 and Pt/C catalysts. The relative current decay for OER and ORR is only 7% and 14% for the Co3O4 catalyst, while RuO2 and Pt/C catalysts show larger decreases in stability.