Benmami M, Chhor K, Kanaev A V
Laboratoire d'Ingénierie des Matériaux et des Hautes Pressions, C.N.R.S., Institut Galilée, Université Paris-Nord, 93430 Villetaneuse, France.
J Phys Chem B. 2005 Oct 27;109(42):19766-71. doi: 10.1021/jp051396+.
We report on the first study of the photocatalytic performance of immobilized smallest titanium oxide oxoparticles of the size 2R = 5.0 nm on a glass support. The nanometric particles are prepared in the sol-gel reactor with rapid reagent mixing and temperature, atmosphere, and particle size control. The surface coverage is achieved by inserting the support into the reactor solution during the induction period, where chemically active nanoparticles are relatively stable. We show that this immobilized amorphous oxo phase of titanium oxide exhibits considerable activity toward photocatalytic degradation of trichloroethylene in the gas phase. Moreover, one of the important factors appears to be the catalyst surface preparation, which has to be free of the adsorbed alcohol molecules. UV-assisted exchange between propoxy and hydroxy groups is suggested as the surface activation mechanism. The film thickness is expected to strongly affect the material photocatalytic efficiency because of the internal traps population.
我们报道了关于在玻璃载体上固定尺寸为2R = 5.0 nm的最小氧化钛氧粒子的光催化性能的首次研究。纳米粒子在溶胶 - 凝胶反应器中制备，具有快速的试剂混合以及温度、气氛和粒径控制。通过在诱导期将载体插入反应器溶液中来实现表面覆盖，在此期间化学活性纳米粒子相对稳定。我们表明，这种固定化的非晶态氧化钛氧相在气相中对三氯乙烯的光催化降解表现出相当大的活性。此外，一个重要因素似乎是催化剂表面制备，其必须不含吸附的醇分子。建议丙氧基和羟基之间的紫外辅助交换作为表面活化机制。由于内部陷阱数量，预计膜厚度会强烈影响材料的光催化效率。
