The IV period transition metal modified carbon@TiO2 nanoflower with high photo-electrochemical water oxidation performance under solar irradiation

Abstract

Improving the photo-electrochemical water oxidation performance (PEWOP) of pristine TiO2 has been seriously hampered by its poor carrier transport efficiency and sluggish surface water oxidation kinetics. In this work, we prepared a novel IV period transition metal modified carbon layer-coated TiO2 (M-C@TiO2) nanoflower via a facile hydrothermal process followed by annealing at 800 °C. The as-prepared M-C@TiO2 nanoflower is uniform and stable with the size < 600 nm. The PEWOP of different IV period transition metal Zn, Cu, Ni, Co, Fe, Mn and Cr modified M-C@TiO2 nanoflowers are systematically investigated. Among them, the Cu, Ni, and Mn metals show high sensitivity to the current response in the modified nanoflowers. The current density of as-prepared Cu0.1-C@TiO2, Ni0.5-C@TiO2, and Mn1.0-C@TiO2 nanoflowers are increased to 4.6, 6.7 and 6.2 times higher than that of pristine TiO2, respectively, implying a significant enhancement to the PEWOP of pristine TiO2. This work provides an effective way to significantly enhance the PEWOP of pristine TiO2. Furthermore, it may arouse new interest and insight for the designing and preparing of M-C@TiO2 nanostructures for large-scale and practical water oxidation applications.