On Activity and Stability of Rhombohedral LaNiO3 Catalyst towards ORR and OER in Alkaline Electrolyte

Abstract

LaNiO3 catalyst was synthesized by RHP method and sprayed onto a GDL. Electrochemical activity for oxygen reactions of as-prepared GDE was evaluated under half-cell condition in oxygen-saturated 7 M KOH electrolyte. Best performance in terms of potential difference ΔE between ORR and OER amounted 0.688 V @ 10 mA cm−2 for 20 wt% LaNiO3/CHSAG compared to 1 V for 20 wt% Pt/CVulcan. Moreover, by increasing perovskite:carbon weight ratio up to 3:2, ΔE in oxygen decreased down to 0.57 V that is the lowest value ever reported in the literature. However, phase segregation and loss in ORR activity was observed during cycling.