二氧化钛纳米晶溶胶内渗透电极对染料敏化太阳能电池的光伏性能的提高

以自制的过氧钛酸(PTA)水溶液为前驱体,用水热法制备了透明锐钛矿相二氧化钛溶胶.无需有机添加剂可得到直径小于7 nm的棒状二氧化钛纳米晶溶胶.通过将溶胶内渗透到染料敏化太阳能电池(DSSCs)的多孔二氧化钛电极后,消除了多孔电极内的大孔并改善了电极内纳米晶之间的连通性.用扫描电子显微镜(SEM)和光学轮廓仪对溶胶内渗透后的光阳极进行了表征.结果表明:小颗粒棒状二氧化钛纳米晶附着在多孔的二氧化钛表面,填充了电极由于烧结产生的大孔,并在多孔的二氧化钛内部形成了有利于电子传输的网络结构.与未经处理的多孔电极相比,改性后的光阳极组装成染料敏化太阳能电池后光电转化效率提高了64%.

Enhancing the Photovoltaic Performance of Dye Sensitized Solar Cells with the TiO2 Sol Infiltrated Nanocrystalline Electrode

Transparent anatase titanium dioxide sol was prepared by the hydrothermal treatment of the home-made water soluble peroxotitanium acid (PTA). The nanorod-like TiO₂ nanocrystals witha mean diameter of less than7 nm were obtained in the absence of organic compounds. In order to eliminate the large pores derived from eletrode sintering and improve the connectivity among particles in the porous TiO₂ electrode, the as-prepared TiO₂ sol was infiltrated to the porous TiO₂ photoanode for dye sensitized solar cells (DSSCs). As a result, small nanocrystals of titanium dioxide attached to the surface of porous titanium dioxide as well as filled the large pores produced by photoanode sintering. The efficient electron transport networks were formed inside the porous titanium dioxide, which was confirmed by scanning electron microscope (SEM) and optical profilometry. The modified TiO₂ film as the anodic electrode was used for the DSSCs and assembled into solar cells. Consequently, the overall energy conversion efficiency of the DSSCs was significantly enhanced by 64% after the low-concentration TiO₂ sol infiltration.