Advances, practical applications, and future prospects of layered perovskite oxides (LnBaCo2O5+δ) for electrocatalysis reactions

Abstract

To realize a sustainable and clean society, highly efficient and eco-friendly energy conversion and production technologies have been developed, such as solid oxide cells (SOCs) and water electrolysis. However, most electrocatalytic reactions are normally driven by scarce noble metal-based catalysts. Thus, the exploration of active, stable, and cost-effective electrocatalysts remains an essential challenge. Herein, we summarize a series of layered perovskite oxides (LnBaCo₂O_5+δ) demonstrating attractive oxygen reduction, oxygen evolution, and hydrogen evolution electrolysis activities. Their variable crystal structures, flexible elemental compositions, and regulated electronic structures endow them with satisfactory activity for electrocatalytic water electrolysis and SOCs (fuel cells and electrolysis cells). This review summarizes the advances in LnBCO-based electrocatalysts and addresses several issues in their development and usage, including structural evolution, fundamental electrical properties, electrocatalytic mechanism and performance, structure–property–performance relationship, activity descriptors, and real merits/demerits. Finally, we outline the opportunities and challenges of layered perovskite oxides for practical applications, encouraging future research on next-generation electrocatalysts applied in an environmentally friendly society.