Platinum nanoclusters by atomic layer deposition on three-dimensional TiO2 nanotube array for efficient hydrogen evolution

Electrode design plays an important role in improving hydrogen evolution reaction (HER), and the self-supporting electrode with three-dimensional (3D) porous structure is widely adopted in the electrocatalytic hydrogen evolution. To better the performance of Pt catalyst for hydrogen evolution, a layer of TiO2 nanotube arrays (TiO2 NTs) fabricated on titanium mesh (3D-Ti) or plate Ti (P-Ti) substrate, respectively, has been selected as support materials to load Pt nanocluster (Pt-x/TiO2 NTs@3D-Ti and Pt-x/TiO2 NTs@P-Ti) via an atomic layer deposition method. It has been revealed that one chemical bond of Ti-O-Pt had been formed between Pt nanocluster and TiO2 nanotube. The theoretical calculations confirm that Ti-O-Pt bond can not only improve the stability of Pt nanocluster but also improve its capability for hydrogen evolution. In addition, the 3D-Ti substrate with open structure can further better Pt nanoclusters' performance on hydrogen evolution. The obtained Pt-x/TiO2 NTs@3D-Ti electrode exhibits an overpotential of 53 mV in 0.5 M H2SO4 at -10 mA cm(-2), and its mass activity has been improved by a factor of 18 compared with Pt-x/TiO2 NTs@P-Ti. (c) 2022 Elsevier Ltd. All rights reserved.

Automated summary

In this study, the performance of Pt catalyst for hydrogen evolution was improved by fabricating TiO2 nanotube arrays on titanium substrate and subsequently loading Pt nanoclusters through chemical bonding. The stability and capability for hydrogen evolution of Pt catalyst were enhanced by the Ti-O-Pt bond. Furthermore, the 3D porous titanium substrate with open structure further improved the performance of hydrogen evolution reaction.