Department of Environmental Engineering, Zhejiang University, Hangzhou 310058, China.
J Hazard Mater. 2011 Sep 15;192(3):1548-54. doi: 10.1016/j.jhazmat.2011.06.073. Epub 2011 Jul 1.
Mesoporous wide bandgap semiconductors offer high photocatalytic oxidation and mineralization activities. In this study, mesoporous β-Ga(2)O(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(2)O(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(2)O(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(2)O(3) nanorods with a η value of 9.6 are much safer than TiO(2) (η = 17.6).
介孔宽带隙半导体具有高的光催化氧化和矿化活性。本研究采用基于尿素的水热法，以聚乙二醇（PEG）为模板剂，合成了直径为 200-300nm、长度为 1.0-1.2μm 的介孔β-Ga2O3 金刚石纳米棒。评价了β-Ga2O3 对甲苯气体的紫外光催化氧化活性，通过质子转移反应质谱在线监测到 7 种中间产物。光致发光光谱表明，PEG 的用量和分子量对形成空位和光催化氧化活性至关重要。提出了一种介孔β-Ga2O3 金刚石纳米棒的 PEG 辅助水热形成机理。根据中间产物的健康风险影响指数（η），计算出的健康风险表明，η 值为 9.6 的β-Ga2O3 纳米棒比 TiO2（η=17.6）安全得多。
