Deciphering the Superior Electronic Transmission Induced by the Li–N Ligand Pairs Boosted Photocatalytic Hydrogen Evolution

Abstract Atomic level decoration route is designated as one of the attractive methods to regulate both the charge density and band structure of photocatalysts. Moreover, to enable more efficient separation and transport of photocarriers, the construction of novel active sites can enhance both the reactivity and electrical conductivity of the crystal. Herein, an Li–N ligand is constructed via co‐doping lithium and nitrogen atoms into ZnIn₂S₄ lattice, which achieves a promoted photocatalytic H₂ evolution at 9737 µmol g⁻¹ h⁻¹. The existence of Li–N ligand pairs and the behaviors of photocarriers on L₄₀N₅ZIS are determined systematically, which also provides a unique insight into the mechanism of the improved photocarrier migration rate. With the introduction of Li–N dual sites, the vacancy form of ZnIn₂S₄ has changed and the photocatalytic stability is significantly improved. Interestingly, the change of charge density around Li–N ligand in ZnIn₂S₄ is determined by theoretical simulations, as well as the regulated energy barrier of photocatalytic water splitting caused by Li–N dual sites, which act as both adsorption site for H₂O and stronger reactive sites. This work helps to extend the understanding of ZnIn₂S₄ and offers a fresh perspective for the creation of a Li–N co‐doped photocatalyst.