Abstract: The fundamental water cycle, carbon cycle and nitrogen cycle relying on heterogeneous gas-involving electrocatalytic processes have attracted extensive attention due to their critical contributions to clean, sustainable and energy-environmental electrochemical devices. The development of electrocatalytic materials has afforded gradually improved electrocatalytic reaction efficiency and increasingly promising implementation of electrochemical techniques. In gas-involving electrocatalytic reactions, apart from the intrinsic reaction kinetics, the microenvironment at the triple-phase interfaces of the solid catalyst, liquid electrolyte and gaseous reactant or product under reaction conditions can exert a significant effect on the eventual electrochemical performance since the key issues, including mass transport, electron conduction and accessibility of active sites, are highly sensitive to the electrocatalytic processes. Herein, we systematically summarize the up-to-date progress in energy-related electrocatalysts based on gas-liquid-solid triple-phase interface engineering in terms of an active-site-enriched surface, decent gas wettability and electrolyte infiltration and favorable electronic conductivity. To establish universal theory-structure-function relationships based on triple-phase interface engineering, the corresponding insightful understanding, architecture design/constituent regulation of electrocatalytic materials and admirable electrocatalytic activity are discussed, simultaneously revealing the practical energy-related applications in water electrolyzers, metal-based batteries and fuel cells. Finally, the remaining challenges, possible opportunities and future perspectives are highlighted.

Key words: Gas-liquid-solid triple-phase interface, Electrocatalysts, Gas-involving electrocatalysis, Energy conversion reactions, Electrochemical energy-related devices