Highly Aligned Oxide Nanotubes: Engineering Reactive Centers for Photocatalysis

Abstract

TiO2 nanomaterials have over the last 30 years attracted tremendous scientific and technological interest. Particularly various 1D and highly defined TiO2 morphologies were explored for the replacement of nanoparticle networks and were found in many cases far superior to nanoparticles or their assemblies. Nanotubes or wires can be grown by hydrothermal or template methods, or even more elegantly, by self-organizing anodic oxidation. The latter is not limited to TiO2 but to a full range of other functional oxide structures on various metals and alloys can be formed. These advanced and doped morphologies can be grown on conductive substrates as ordered layers and therefore can be directly used as functional electrodes (e.g. photo-anodes). The presentation will focus on these highly ordered nanotube arrays of TiO2 (and similar) and discuss most recent progress in synthesis, modification and applications towards photocatalytic and photoelectrochemical applications such as noble-metal-free H2 generation or the site-selective placement of active centers onto/into these tube layers. Literature: - P. Roy, S. Berger, P. Schmuki, Angew. Chem. Int. Ed. (2011), 2904 - K. Lee, A. Mazare, P. Schmuki, CHEMICAL REVIEWS, 114 (2014) 9385 - N. Liu, P. Schmuki et.al. Nano Letters, 14 (2014) 3309 - N. Liu, P. Schmuki et.al. Angew. Chem. Int. Ed. 53 (2014) 14201 - X. Zhou, N.Liu, P.Schmuki ACS Catal., ,7 (2017) 3210