Self-Assembling Oxide Catalyst for Electrochemical Water Splitting

TL;DR

This paper introduces a novel self-assembling perovskite-based oxide catalyst with enhanced stability and performance for water electrolysis, addressing long-term degradation issues of existing catalysts.

Contribution

It reports a new BaCo0.98Ti0.02O3-$ ext{δ}$:Co3O4 catalyst with superior stability and performance, and provides design rules for developing oxide electrocatalysts.

Findings

Outperforms current state-of-the-art catalysts

Maintains properties at 353 K without degradation

Identifies degradation mechanisms and improves stability

Abstract

Renewable energy conversion and storage, and greenhouse gas emission-free technologies are within the primary tasks and challenges for the society. Hydrogen fuel, produced by alkaline water electrolysis is fulfilling all these demands, however the technology is economically feeble, limited by the slow rate of oxygen evolution reaction. Complex metal oxides were suggested to overcome this problem being low-cost efficient catalysts. However, the insufficient long-term stability, degradation of structure and electrocatalytic activity are restricting their utilization. Here we report on a new perovskite-based self-assembling material BaCo0.98Ti0.02O3-$\delta$:Co3O4 with superior performance, showing outstanding properties compared to current state-of-the-art materials without degeneration of its properties even at 353 K. By chemical and structural analysis the degradation mechanism was identified and modified by selective doping. Short-range order and chemical composition rather than long-range order are factors determining the outstanding performance. The derived general design rules can be used for further development of oxide-based electrocatalytic materials.