Unveiling Halide Perovskites: An Emerging Electrocatalyst for Oxygen and Hydrogen Electrocatalysis

Abstract Halide perovskites are a significant class of compounds with ABX 3 crystal structure and have shown remarkable potential in renewable energy applications such as supercapacitors, photocatalysis, and photo‐electrocatalysis. Their efficient charge carrier mobility, superior optoelectronic properties derived from optimal bandgap and tunable composition are beneficial for the applications of halide perovskites in the sustainable energy conversion and storage field. This review highlights the inherent potential of halide perovskites as electrocatalysts for oxygen and hydrogen electrocatalysis. Oxygen evolution reaction (OER), oxygen reduction reaction (ORR), and hydrogen evolution reaction (HER) are the bottlenecks for sustainable water splitting reactions, for fuel cells, metal‐air batteries, etc., which require electrocatalysts that offer good activity and excellent stability. Though noble metal catalysts offer thriving performance, their cost and stability‐related issues hinder their widespread usage. Non‐noble metal‐based perovskite oxide has already established its stronghold in electrocatalysis. Similarly, their halogen counterpart, perovskite halides, also prove to be efficient contenders for noble metal‐free electrocatalysts. In this review, various suitable synthesis techniques, mechanisms, and the electrocatalytic activity of halide perovskites are discussed. This review aims to show yet another class of compounds (halide perovskites) to the researcher community that strives for the development of noble metal‐free electrocatalysts for sustainable energy applications.