Characterization of microwave effects on metal-oxide materials: Zinc oxide and titanium dioxide
Characterization of microwave effects on metal-oxide materials: Zinc oxide and titanium dioxide
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DOI：
10.1016/j.apcatb.2009.06.008
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发表时间：
2009-09-07
影响因子：
22.1
通讯作者：
Serpone, Nick
中科院分区：
文献类型：
--
作者：
Horikoshi, Satoshi;Matsubara, Akihiro;Serpone, Nick
通过比较在富磁场条件下和在磁场/电场条件下发生的过程，检查可以影响在ZnO或TiO 2（P-25）颗粒表面上发生的微波辅助和光辅助反应的微波特定效应。在微波存在下，在磁场（H）和电场（E）丰富的光辅助过程的特点描述的基础上（i）的降解动力学的4-氯苯酚（4-CP）在环境温度下，（ii）的（OH）-O-中心点自由基的数量，（iii）的金属氧化物（在丸状）的介电性能。对于ZnO，光活性通过源自微波磁场的微波特异性非热（即无热量）效应而增强，但通过源自微波电场的热（即热量）因子而降低。与ZnO相反，微波辐射的磁场和电场之间的协同效应增强了TiO 2（P-25）的光活性。在UV、MW-EH和UV/MW-EH照射条件下，ZnO在水性分散体中的光腐蚀小得可以忽略（小于0.05%）。(C)2009 Elsevier B. V.保留所有权利。
The microwave specific effect(s) that can impact a microwave-assisted and photo-assisted reaction occurring on the surface of ZnO or TiO2 (P-25) particles was (were) examined by comparing the process occurring under rich magnetic field conditions and under magnetic/electric field conditions. The features of the photo-assisted process in the presence of microwaves rich in a magnetic field (H) and an electric field (E) are described on the basis of (i) the degradation dynamics of 4-chlorophenol (4-CP) at ambient temperatures, (ii) the number of (OH)-O-center dot radicals produced, and (iii) the dielectric properties of the metal oxides (in pellet form). For ZnO, the photoactivity is enhanced by a microwave specific non-thermal (i.e. non-caloric) effect originating from the microwaves' magnetic field, but decreased by the thermal (i.e. caloric) factor originating from the microwaves' electric field. Contrary to ZnO, the photoactivity of TiO2 (P-25) was enhanced by the synergistic effect between the magnetic and electric fields of the microwave radiation. Photocorrosion of ZnO in the aqueous dispersions was negligibly small (less than 0.05%) under UV, MW-EH, and UV/MW-EH irradiation conditions. (C) 2009 Elsevier B.V. All rights reserved.