Synthesis of Core/Shell Ti/TiOx Photocatalyst via Single-Mode Magnetic Microwave Assisted Direct Oxidation of TiH2

TL;DR

This paper reports a novel synthesis of submicron Ti/TiOx core/shell photocatalysts using single-mode magnetic microwave-assisted oxidation, resulting in highly efficient visible-light-driven hydrogen production.

Contribution

The study introduces a new microwave-assisted method to synthesize Ti/TiOx photocatalysts with controllable shell thickness and enhanced photocatalytic performance under visible light.

Findings

Achieved controllable TiOx shell thickness from 6 to 18 nm.

Demonstrated superior H2 production efficiency compared to commercial TiO2.

Enhanced visible-light absorption due to surface defects and core/shell structure.

Abstract

Submicron core/shell Ti/TiOx photocatalyst is successfully synthesized via single-mode magnetic microwave (SMMW) assisted direct oxidation of planetary ball-milled TiH2. The thickness of TiOx shell including highly concentrated defects such as Ti3+ and/or oxygen vacancies is controllable in the range from 6 to over 18 nm by varying the treatment time in the SMMW assisted reaction. In addition to its quite narrow optical bandgap (1.34-2.69 eV) and efficient visible-light absorption capacity, the submicron Ti/TiOx particle exhibits superior photocatalytic performance towards H2 production from water under both UV and visible-light irradiation to compare with a commercial TiO2 photocatalyst (P-25). Such excellent performance can be achieved by the synergetic effect of enhancement in visible light absorption capacity and photo-excited carrier separation because of the highly concentrated surface defects and the specific Ti/TiOx core/shell structure, respectively.