Abstract A biphasic sol–gel method was introduced to reduce a high hydrolysis rate of metal alkoxides and control a morphological evolution of metal oxides. Titanium tetraisopropoxide (TTIP) was dissolved in an organic solvent which was immiscible with water. The TTIP solution was then contacted with water or pH-controlled aqueous solutions to promote the hydrolysis and the polycondensation reaction through the mass transfer across the organic/aqueous interface. Anatase TiO2 was formed in any conditions employed in the present work at reaction temperatures of 80 °C or below. The morphology of TiO2 particles obtained was largely dependent on the kind of organic solvents. It was basically the aggregation of nanoparticles to give submicrometer-sized secondary particles with or without a regular shape. Heptane was found to be suitable to obtain spherical TiO2 large particles, which were evaluated as a photoanode material in dye-sensitized solar cells. Actually the large TiO2 particles worked well as the light scattering layer when applying them to a double-layered phtoanode, which showed an energy conversion efficiency of 5.67% with a high short-circuit photocurrent density of 14.1 mA cm−2.

中文翻译：

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在受控条件下合成锐钛矿 TiO 2 颗粒的双相溶胶-凝胶途径及其 DSSC 应用

摘要 引入双相溶胶-凝胶法来降低金属醇盐的高水解速率并控制金属氧化物的形态演变。将四异丙醇钛 (TTIP) 溶解在与水不混溶的有机溶剂中。然后将 TTIP 溶液与水或 pH 控制的水溶液接触，以通过有机/水界面上的传质促进水解和缩聚反应。锐钛矿 TiO2 在本工作中采用的任何条件下在 80°C 或更低的反应温度下形成。获得的二氧化钛颗粒的形态在很大程度上取决于有机溶剂的种类。它基本上是纳米粒子的聚集，以产生具有或不具有规则形状的亚微米级二次粒子。发现庚烷适用于获得球形 TiO2 大颗粒，该颗粒被评估为染料敏化太阳能电池中的光电阳极材料。实际上，当将大 TiO2 颗粒应用于双层光阳极时，它们作为光散射层工作得很好，其能量转换效率为 5.67%，短路光电流密度为 14.1 mA cm-2。