【作者】 冯艳文；

【导师】 梁广川； 梁金生；

【作者基本信息】 河北工业大学 ， 材料物理与化学， 2004， 硕士

【摘要】 本工作利用电气石矿物材料的天然电极性、辐射红外线性能和TiO₂的光催化性能，研制以电气石为载体，TiO₂薄膜和[TiO₂，SiO₂]复合薄膜为催化剂的新型复合催化材料。研究材料的制备技术、结构、性能及电气石表面TiO₂晶体生长机理、电气石增强TiO₂光催化效率机理。 用溶胶—凝胶技术在紫铜网表面成功生长电气石／TiO₂复合薄膜，该复合膜中电气石微粒表面形成了TiO₂空心球簇结构和TiO₂层状微粒簇结构。空心球平均粒径为2μm；TiO₂微粒簇平均直径为10μm，TiO₂微粒平均粒径为2μm，阶梯层厚度为10nm，表面凸起平均粒径15nm。研究表明，电气石／TiO₂复合薄膜的光催化效率比不含电气石的TiO₂薄膜提高15.6％。 电气石／[TiO₂，SiO₂]复合催化剂的最佳制备工艺参数为：[TiO₂，SiO₂]复合膜中SiO₂的质量分数为10％，热处理温度为600℃，热处理时间为3h。该复合催化剂对初始浓度为10mg／L的甲基澄溶液的光催化降解率（3h）达到97％以上，比电气石／TiO₂复合催化剂提高14.3％。 通过电气石促进TiO₂光催化反应机理的研究发现，在电气石／TiO₂光催化剂体系中，电气石天然电场不仅能够吸引并牢固的捕获由TiO₂在紫外线激发下产生的光生电子，避免光生电子和光生空穴发生再复合反应，而且能够电离水分子，促进羟基自由基的生成。同时，电气石辐射的红外线能够降低水分子团的直径，引起有机高分子强烈共振，加速光催化反应速度。更多还原

【Abstract】 A kind of novel composite photocatalysts containing TiO2 and tourmaline particles, such as tourmaline/TiO2 composite photocatalysts and tourmaline/[TiO2, SiO2] composite photocalysts, were fabricated mainly by the sol-gel technique, whose microstructure, photocatalystic activities and spontaneous polarization were investigated by the scanning electron microscope(SEM), UV-visible spectro-photometer, etc.The novel porous composite films of tourmaline/TiO2 were prepared from alkoxide solutions on the surface of copper by sol-gel method. Results show that the empty and porous balls of TiO2 were grown on the surface of fine tourmaline particles dispersing in the TiO2 film based on the copper net, under the effect of the nature electric field of fine tourmaline particles. The average diameter of the empty balls is 2 μm, and the photocatalystic degradation ratio of methyl orange increased by 15.6% with the composite film of TiO2 containing 0.5 wt % tourmaline than with the thin films of TiO2 under the irradiation of ultraviolet.In this paper, not only a new method to testify the spontaneous polarization of tourmaline is provided, but also the influence of treatment temperature on the spontaneous polarization of tourmaline/[TiO2, SiO2] composite photocatalysts containing 10wt% SiO2 are observed. Results show that tourmaline/[TiO2, SiO2] composite photocatalysts granules, under the bombardment by electron beam in SEM, will turn to be brighter and attract each other, and the electrostatic gravitation among the tourmaline/[TiO2, SiO2] composite photocatalysts granules grow up evidently on their surfaces with the accumulations of electron from the electron probe, so as to be strong enough to force the tourmaline/[TiO2, SiO2] composite photocatalysts granules be shifted rapidly and accumulated into clusters ultimately.Photocatalytic activities and mutual interactions mechanism between TiO2 and fine tourmaline particles were investigated, respectively. Photoelectrocalalytic reaction happens in the reaction system, in which electrons and cavities generated from nanometer TiO2 under irradiation of ultraviolet will be avoided compounding due to existence of permanent and strongly electric field of fine tourmaline powders.更多还原