Self-Supported Electrocatalyst Engineering for Electrochemical Hydrogen Energy Conversion

Electrocatalytic materials constitute the cornerstone of sustainable energy technologies, enabling key processes including hydrogen evolution reaction (HER), oxygen evolution reaction (OER), and oxygen reduction reaction (ORR). Traditional powdered catalysts continue to dominate; however, their fundamental restrictions stem from the requirement for binders and conductive additives. These nonelectrochemically active components will obstruct the active sites, accelerate structural degradation during cycling, and compromise mechanical stability under prolonged operation. Despite recent advancements in electrocatalyst design, there is still a lack of systematic evaluation of self-supported structures, which are integrated configurations that combine active materials with conductive substrates without binders. This review comprehensively analyzes 3D self-supported electrocatalysts, elucidating their structural characteristics, performance superiority, and diverse application fields, while also forecasting their promising future development potential. The intrinsic effects of synthesis parameters (temperature, atmosphere, and reaction time) on the performance of the catalyst are explored, encompassing HER, OER, and ORR. This review aims to offer insightful thoughts and suggestions for subsequent researchers, identify potential directions to design more effective self-supported electrocatalysts, and offer innovative pathways for the development of electrochemical energy infrastructure.