Strong heterostructure coupling-confinement effect inducing dispersion of Cu-based catalysts for photocatalytic hydrogen evolution

Nonprecious transition metal copper-based catalysts have attracted immense research interest for several applications due to their cost-effectiveness. However, deactivation by agglomeration in high-temperature environments remains a pervasive challenge and limits their uses. Here, we show the controllable dispersion of ultrafine copper nanocomposites among the linear polyimide by a strong CuO x /WO x (WCuO x ) heterostructure coupling. The strong interaction triggered by coupling-confinement confines the mobility of Cu species, preventing the agglomeration or the formation of large metal particles. Abundantly exposed catalytic sites with unique electronic structures optimized the adsorption activation of H 2 O and the reaction energy barrier. This study provides a novel and significant insight into the surface-confinement strategy and lays the foundation for the design of Cu-based catalyst site distribution.