TiO_2介孔球的形貌控制及其在染料敏化太阳能电池中的应用研究

Synthesis of mesoporous titania beads with controllable morphology and application in dye-sensitized solar cells

本文通过简单溶胶-凝胶和溶剂热后处理反应,以价格低廉、相对环保正己胺作结构向剂合成尺寸分均匀、孔径为18.9nm、比表面积为89.76m2g-1锐钛矿相TiO2介孔球.通过使用不同烷基碳链长度有胺作为结构向剂合成介孔球研究表明:较长烷碳链,有利于形成质量较高的TiO2介孔球;但是,只有当有胺烷碳链长度适中时,能获形貌最佳TiO2介孔球.改变水与钛源摩尔比可实现TiO2介孔球直径在300-1400nm间有效调节.延长反应时间,球表面越来越光滑,直径逐渐增加,最后可达近1400nm.选用正己胺为结构向剂、添加水、反应18h并经溶剂热后处理TiO2介孔球作为染料敏化太能电池光极料,吸附N719染料后敏化太能电池光电转化效率达5.56%,与相同条件下用P25作光极料效率(5.27%)相比提高5.5%,初步显示了TiO2介孔球在太能利用领域中应用潜力.

Monodisperse anatase titania mesoporous beads with a pore size of 18.9 nm and high surface areas of 89.76 m2 g-1 were synthesized using hexylamine as a structure-directing agent by a facile sol-gel procedure, followed by a solvothermal post-treatment. It was found that the H20 contents in the synthesis affected significantly the morphology of the resultant TiO2 beads. The roughness and diameters of the beads were also affected by the reaction time： prolonging the reaction time leads to the formation of the beads with smoother surface and bigger size. The TiO2 mesoporous beads were finally employed as the photoanode of DSSCs which show a light-to-electric conversion efficiency of 5.56%, a little higher than that made from P25. This study shows that the titania mesoporous materials may be very useful in the areas such as energy conversion and environmental cleanup.