NiS/Pt nanoparticles co-decorated black mesoporous TiO2 hollow nanotube assemblies as efficient hydrogen evolution photocatalysts

Abstract

A novel mesoporous Pt/NiS/black TiO2 hollow nanotubes (P-NBTNs) is assembled by a facile synthesize route based on hollow black TiO2 nanotubes with 2D mesoporous TiO2 nanosheets. This unique structure increases the specific surface area of the material, exposes more photocatalytic reaction active sites, and reduces the bandgap to about 2.87 eV, thereby improving its light absorption capacity in the visible light region. At the same time, the surface plasmon resonance effect of the noble metal Pt is employed to further improve the absorption and utilization of visible light. The strong electron-withdrawing ability of Pt nanoparticles and the synergistic catalytic between NiS and Pt, and the formation of built-in electric field at the interface all promote the separation and transmission of photo-generated charge carriers, leading to significant improvement of photocatalytic performance. Under AM 1.5 G irradiation, the hydrogen production rate of P-NBTNs is up to 4.70 mmol h−1g−1, which is more than 4 times higher than that of pristine TiO2 nanotubes (TNs) (~0.94 mmol h−1g−1). The photocatalytic performance nearly keeps constant after more than 10 cycles, indicating the high stability of P-NBTNs, which favors the practical applications.