Boosting oxygen evolution reaction activity descriptors in LaNiO3 perovskite oxide via one-pot synthesis for alkaline electrolysis

Abstract

Perovskite oxides have emerged as promising alternatives to platinum group metal based state-of-the-art electrocatalysts for alkaline oxygen evolution reaction, such as RuO2 and IrO2. Specifically, LaNiO3 is a highly efficient OER electrocatalyst in alkaline environment, nevertheless, its performance is strongly dependent on the preparation conditions. In this work, a one-pot solution combustion synthesis (SCS) is presented as a straightforward method to enhance LaNiO3 OER descriptors. The process involves a clever combination of low-cost, easily available fuels: glycine (Gly) and citric acid monohydrate (CAM). The SCS Gly +CAM LaNiO3 is compared to other LaNiO3 samples obtained via sustainable wet-chemistry techniques like coprecipitations and other SCS methods. Although all samples show comparable XRD patterns, the SCS Gly +CAM route ensures superior textural properties and optimal Ni3+/Ni2+ratio, resulting in higher intrinsic OER activity. SCS Gly +CAM displays the lowest overpotential, 377 ±7 mV, further decreasing to 350 ±5 mV after 25 cycles, due to surface reconstruction. Over 25 cycles, SCS Gly +CAM LaNiO3 outperformes the state-of-the-art RuO2. To the best of our knowledge, the Gly +CAM combination has not been explored for LaNiO3 and presents a cost-effective alternative for scaled-up production of high-performance OER electrocatalysts