Interface engineering of 0D–1D Cu2NiSnS4/TiO2(B) p–n heterojunction nanowires for efficient photocatalytic hydrogen evolution

Abstract

The photocatalytic hydrogen production is one of the clean and renewable methods of converting solar energy to chemical fuels. Herein, an 0D/1D Cu2NiSnS4/TiO2(B) p-n heterojunction photocatalyst was prepared by a hydrothermal route. The FE-SEM, and HR-TEM analysis revealed that the 1D nanowire morphology of TiO2(B) was coated uniformly with Cu2NiSnS4 (CNTS) nanoparticles. With an average particle size of 5 nm, CNTS nanoparticles improved the interfacial contact and formed an efficient p-n heterojunction with TiO2(B), which greatly improved the charge carrier separation, as evident from the transient photocurrent, photoluminescence, and impedance spectroscopies. The optimized Cu2NiSnS4/TiO2(B) sample produced an average of 7144 µmol/g of hydrogen in 4 h of reaction time under direct sunlight irradiation, which is nearly five times higher than bare TiO2(B). Based on the Mott-Schottky and UV–visDRS spectra, a Z-scheme p-n junction charge transfer mechanism has been proposed.