Photocatalytic H2 Generation Using Dewetted Pt-Decorated TiO2 Nanotubes: Optimized Dewetting and Oxide Crystallization by a Multiple Annealing Process

• Published in: Journal of physical chemistry. C Vol. 120; no. 29; pp. 15884 - 15892
• Main Authors: Yoo, JeongEun, Altomare, Marco, Mokhtar, Mohamed, Alshehri, Abdelmohsen, Al-Thabaiti, Shaeel A, Mazare, Anca, Schmuki, Patrik
• Format: Journal Article
• Language: English
• Published: American Chemical Society 28-07-2016
• ISSN: 1932-7447; 1932-7455
• DOI: 10.1021/acs.jpcc.5b12050

In the present work we use TiO2 nanotube arrays, deposit onto them a thin layer of Pt, dewet the Pt to nanoparticles, and use the structures as photocatalyst to generate H2. In order to achieve a maximum H2-generation efficiency, on the one hand an optimal thermal dewetting of the Pt layer is needed (this requires an oxygen-free heat treatment), and on the other hand an optimal crystallization of the TiO2 nanotubes into a suitable crystalline oxide is required (achieved by annealing in an O2-containing environment). To combine the two requirements, we provide an adequate multiple annealing treatment under reducing and oxidizing conditions and obtain Pt-nanoparticle-decorated TiO2 nanotubes, composed of an anatase–rutile mixed phase, that show a significantly enhanced photocatalytic H2 generation ability compared to tube layers that underwent any single-step annealing process.