复合分级结构的锐钛矿TiO2纳米花的合成及其光电性能

Synthesis and photo elec trical proper ties of hierarchical-structured anatase TiO2 nanoflowers

半导体氧化物可用于染料敏化太阳能电池光阳极材料。一维纳米结构氧化物比球形纳米粒子具有更高效的电子传输和收集能力。然而,它们受制于因小的比表面积致使低的染料吸附量以及差的电子抽取能力的膜结构。采用一步水热法成功地合成了TiO2纳米花,该纳米花为锐钛矿相并且是由纳米棒作为基本构成单元的复合分级结构。反应时间可以控制该结构的演化。反应时间对这种结构的TiO2纳米花对染料分子的吸附能力有较大影响。最高的电池效率(7.29%)是使用70h反应条件下合成的TiO2纳米花所获得的。

Oxide semiconductor nanomaterials are used as aonde materials for dyesensitized solar cells(DSSCs).One-dimensional nanostructures have enhanced electron collection of carriers and superior charge transport compared to spherical nanoparticles.However,they suffer from low dye-loading caused by small surface areas and unfavorable arrangement for a photo-generated electron extraction.Anatase TiO2 nanorodsbased nanoflowers have been successfully synthesized using a simple one-step hydrothermal method.Such hierarchical nanostructures can be controlled by reaction time.The dye absorption capacities of the as-obtained hierarchical nanostructures increase with the reaction time.The highest cell efficiency(7.29%)of the DSSC is achieved through the TiO2 nanoflowers prepared for 70 h.