Synthesis of mesoporous β-Ga 2O 3 nanorods using PEG as template: Preparation, characterization and photocatalytic properties

Abstract

Mesoporous wide bandgap semiconductors offer high photocatalytic oxidation and mineralization activities. In this study, mesoporous β-Ga 2O 3 diamond nanorods with 200–300 nm in diameter and 1.0–1.2 μm in length were synthesized via a urea-based hydrothermal method using polyethylene glycol (PEG) as template agent. The UV photocatalytic oxidation activity of β-Ga 2O 3 for gaseous toluene was evaluated, and 7 kinds of intermediates were monitored online by a proton transfer reaction mass spectrometry. Photoluminescence spectra manifested that the dosage and molecular weight of PEG are crucial for formation of vacancies and photocatalytic oxidation activities. A PEG-assisted hydrothermal formation mechanism of mesoporous β-Ga 2O 3 diamond nanorods was proposed. Based on the health risk influence index ( η) of the intermediates, the calculated health risks revealed that the β-Ga 2O 3 nanorods with a η value of 9.6 are much safer than TiO 2 ( η = 17.6).