Layer-by-layer self-assembly of TiO2 hierarchical nanosheets with exposed {001} facets as an effective bifunctional layer for dye-sensitized solar cells.
Layer-by-layer self-assembly of TiO2 hierarchical nanosheets with exposed {001} facets as an effective bifunctional layer for dye-sensitized solar cells.
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DOI：
10.1021/am501233q
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发表时间：
2014-06
影响因子：
9.5
通讯作者：
Weiwei Sun;T. Peng;Yumin Liu;Wenjing Yu;Kun Zhang;H. Mehnane;C. Bu;Shishang Guo;Xingzhong Zhao
中科院分区：
文献类型：
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作者：
Weiwei Sun;T. Peng;Yumin Liu;Wenjing Yu;Kun Zhang;H. Mehnane;C. Bu;Shishang Guo;Xingzhong Zhao
通过一步溶剂热反应成功制备了具有{001}晶面的TiO 2分层自组装纳米片。TiO 2层状分级纳米片（TiO 2 LHNs）具有良好的光散射效果和较大的比表面积，这是由于TiO 2 LHNs具有层状分级结构。当应用于染料敏化太阳能电池（DSSC）时，具有暴露的{001}面的逐层分级结构可以有效地增强光捕获和染料吸附，从而增加DSSC的光电流。结果表明，使用TiO 2 LHN作为双功能层的DSSC的光电转换效率（η）为7.70%，与纯Degussa P25（6.37%）作为光阳极相比，提高了21%。这种增强可以主要归因于更好的光散射能力的TiO 2 LHN，更高的染料吸附在TiO 2 LHN {001}面，和更长的寿命的注入电子在TiO 2 LHN相比，P25，这是由紫外可见分光光度法和电化学阻抗谱在相同的条件下检查。TiO 2 LHN的这些显著特性使其成为DSSC双功能散射材料的有希望的候选者。
Layer-by-layer self-assembled TiO2 hierarchical nanosheets with exposed {001} facets have been successfully fabricated via a simple one-step solvothermal reaction. The anatase TiO2 layer-by-layer hierarchical nanosheets (TiO2 LHNs) exhibit favorable light scattering effect and large surface area, owing to their layer-by-layer hierarchical structure. When applied to the dye-sensitized solar cells (DSSCs), the layer-by-layer hierarchical structure with exposed {001} facet could effectively enhance light harvesting and dye adsorption, followed by increasing the photocurrent of DSSCs. As a result, the photoelectric conversion efficiency (η) of 7.70% has been achieved for the DSSCs using TiO2 LHNs as the bifunctional layer, indicating 21% improvement compared to the pure Degussa P25 (6.37%) as photoanode. Such enhancement can be mainly ascribed to the better light scattering capability of TiO2 LHNs, higher dye adsorption on TiO2 LHN {001} facets, and longer lifetime of the injected electrons in TiO2 LHNs compared to P25, which are examined by UV-vis spectrophotometry and electrochemical impedance spectroscopy under the same conditions. These remarkable properties of TiO2 LHNs make it a promising candidate as a bifunctional scattering material for DSSCs.