Amorphous crystalline heterostructure in electrocatalytic 2D platinum group metals

Abstract

Platinum group metals (PGMs), which are widely explored for developing clean energy technologies, have also undergone extensive morphology and composition tuning to enhance catalytic efficiency. Recently, increasing focus has been placed on phase regulation, particularly in identifying amorphous materials or other unconventional phases with favorable atomic arrangements for electrocatalysis. However, amorphous materials typically suffer from poor stability and insufficient electrical conductivity. To address this, amorphous crystalline (ac)–heterophased PGM-based catalysts, especially in their two-dimensional (2D) morphologies, have been developed, balancing the benefits of both phases with abundantly distributed active sites and fast charge carriers across the hetero-interfaces, offering enhanced electrochemical activity and stability compared with their single-phase counterparts. This review examines the design of heterophased 2D (ac)-PGMs, either through post-synthetic modification of crystalline nanosheets or via confined-growth/in situ amorphization. It further highlights their significant impact on electrochemical energy storage and conversion and also emphasizes the current challenges and future directions in the development of these advanced materials for energy applications.