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TiO2空心微球因具有低密度、高活性、易分离而有利于多次重复使用的优点而广受关注.本文介绍一种无氟制备TiO2空心微球的简单方法——磷钨酸钾(K3PW12O40)模板法.首先，将H3PW12O40和KCl溶液混匀，得到白色牛奶状的K3PW12O40模板(式(1))，然后在磁力搅拌下加入一定量的Ti(SO4)2粉末，加热至大约125oC开始回流.回流8 h后，过滤洗涤.滤饼分散在强NaOH溶液中，原位除去K3PW12O40模板(式(2)).最后，将催化剂洗涤到滤液为中性，干燥后即得到TiO2空心微球.3KCl + H3PW12O40= K3PW12O40ˉ+3HCl (1) K3PW12O40+24NaOH =12Na2WO4+ K3PO4+12 H2O (2) Ti(SO4)2+2H2O = TiO2+2H2SO4(3)我们将所制备的TiO2空心微球，采用X射线衍射、透射电子显微镜、扫描电子显微镜、傅立叶红外光谱、固体粉末漫反射和X射线光电子能谱等进行了表征.采用紫外光催化降解阴离子染料(活性嫣红X3B)来评价催化剂的性能.实验结果显示：(1)所制TiO2空心微球直径在0.5–1.0μm；(2)磷钨酸钾模板剂充当晶核，有利于空心微球的晶化；(3)加入的高浓度硫酸钛，水解产生大量的硫酸，抑制硫酸钛水解，不利于TiO2空心微球的晶化(式(3))；(4)催化剂的活性随着硫酸钛量的增加而先增后降.4 mmol硫酸钛用量的TiO2空心微球具有最高的光催化活性，是TiO2颗粒样品(无磷钨酸钾模板法制备)的2.1倍.用该方法制备的TiO2空心微球活性高可归因于以下主要原因：(1)TiO2空心微球独特的孔结构；(2)良好的晶化程度(TiO2样品晶化度越高，越有利于光生载流子的分离，抑制复合)；(3)样品残余磷钨酸钾模板和TiO2之间存在光生电子转移，有利于空心微球TiO2活性的提高.该法具有操作简单、重复性好、易于批量制备的等优点，有望广泛应用于(光)催化、电化学、分离与纯化以及药物缓释等领域.

Fabrication of TiO2 hollow microspheres (TiO2‐HMSs) has attracted considerable attention owing to their low density, high photoreactivity, and easy to separate and reuse. A fluoride‐free method for the fabrication of TiO2‐HMSs is reported by refluxing a mixed solution of H3PW12O40 (0.4 mmol), KCl (2.5 mmol) and Ti(SO4)2 (2–25 mmol) at 125 °C for 8 h, followed by decomposition of the K3PW12O40 (KPW) template in basic solution. The prepared TiO2‐HMSs are characterized by X‐ray diffraction, transmission electron microscopy, scanning electron microscopy, Fourier transform infrared spec‐troscopy, ultraviolet‐visible diffuse reflectance spectroscopy and X‐ray photoelectron spectroscopy. The activities of the photocatalysts are evaluated by photocatalytic degradation of Brilliant Red X‐3B, an anionic dye, under UV irradiation. It is observed that the TiO2‐HMSs exhibit diameters of approximately 0.5–1μm, and the photocatalytic activity of TiO2‐HMSs initially increases and then decreases with an increasing amount of Ti(SO4)2. The TiO2‐HMSs prepared in the presence of 4 mmol Ti(SO4)2 exhibit the highest photocatalytic activity, which is 2.1 times higher than TiO2 nano‐particles (prepared in the absence of the KPW template). The enhanced photocatalytic activity of the prepared TiO2‐HMSs is ascribed to the improved crystallization, coupling effect between TiO2 and the residual KPW template, and the unique hollow structures of TiO2‐HMSs.