Non-metal doping induced dual p-n charge properties in a single ZnIn2S4 crystal structure provoking charge transfer behaviors and boosting photocatalytic hydrogen generation
Wei‐Kean Chong, Boon‐Junn Ng, Xin Ying Kong, Lling‐Lling Tan, Lutfi Kurnianditia Putri, Siang‐Piao Chai
Abstract
Construction of heterojunction is conventionally regarded as the prevailing technique to render effective solar-driven photocatalytic water splitting. Nonetheless, realization of p-n homojunction emerges to be an appealing scheme attributed to the non-defective layer coupling and minor charge transfer impedance. Herein, nitrogen-doped ZnIn2S4 (N-ZIS) with dual p-n charge properties was facilely synthesized via one-step in-situ solvothermal method. Systematic investigations unveil that the substituting phenomenon of hosting S by extrinsic N atom with dissimilar electronegativity and valence electron, which eventually ameliorates charge transfer rate and inhibits electron-hole pairs recombination. First-principle density functional theory calculations affirm the p-nature induced by N-doping imparting favorable charge redistribution in the ZIS framework and diminishing hydrogen (H2) evolution reaction kinetic barrier at the surface-active sites. Therein, optimal N-ZIS generated 1575.71 μmol∙g-1 of H2 under 6-hour visible-light irradiation (with an apparent quantum yield of 6.59% at 420 nm monochromatic light irradiation), which is 6.35-fold than the pristine counterpart.