Boosted Photocatalytic Hydrogen Production Over One-Dimensional S-Doped Bi4te3 Nanostructures

Abstract

Non-metal doping engineering acts an essential role in the field of photoelectric conversion reactions, and can influence the activity of nanocatalysts by modifying the number and structure of active sites. Herein one-dimensional S-doped Bi4Te3 nanostructure was fabricated for promoted photocatalytic hydrogen production for the first time. Based on plenty of experiment data and density functional theory calculations, S atoms are regarded as the active sites in the designed catalyst system. It is deduced that S-doped Bi4Te3 nanowires have more powerful interfacial charge separation and lower electron transfer resistance compared to pure Bi4Te3 nanowires. Moreover, the doping of S leads to the atomic disorder with enlarged Bi-Te bond length. The changes in the bond length and angle from the atomic arrangements could modify the electronic structure and charge redistribution, which thus affect the interfacial electrochemical reactions between electrode/electrolyte. Under simulated solar irradiation, the hydrogen production rate is 320 μmol·g-1·h-1 for the S-doped Bi4Te3 nanowires, which is ~200 times higher than that of pristine Bi4Te3 nanowires. This work offers some inspiration for constructing an upgradable photochemical system with doping engineering assistance for efficient utilization and conversion of solar energy.

Keywords: S-doped Bi4Te3 nanowires, non-metal doping, photocatalytic hydrogen production, interfacial charge separation, electron transfer resistance