基于旋节分相结构的染料敏化太阳电池阳极薄膜研究

The general nanoparticle TiO2 thin film anode used for the dye-sensitized solar cell (DSSCs) can be said to have a large specific surface area. However, it should be recognized that the boundaries among the contacting nanoparticles can work as the recombination centers, which would inhibit the migration of the photogenerated electrons to the collector. The spinodal phase separation structure (SPSS) films are of the desirable structures since they simultaneously show well-defined consecutive TiO2 skeleton structure, having less TiO2 grain bottleneck, and possess a high specific surface area for the dye adsorption. All of these advantages can effectively improve the photoelectric properties of the DSSCs. In the present study, TiO2 films with SPSS will be fabricated by using the polymerization raction of organic monomer. Comparaed with the conventional sol-gel method, the SPSS can be easilier fabricated in our study. The entire surface of the as-prepared film exhibit the unique SPSS structure. The structures of the film are strongly affected by the solution composition and can be easily controlled by the adjustment of the reaction condition, initial composition of component and type of monomers. The effect of the reactive monomer, the monomer concentration, the polymerization reaction condition, the composition of the start precursor solution, deposition process and heat-treatment condition on the morphology of the films will be carefully studied. In order to comprehend the reaction kinetics, theory simulations will be used to describe the phase separation process. The purpose of the study is to realize the controllable preparation of the films by establishing the relationship between the films structure and the preparation conditions, and finding the formation mechanism of the films The photoelectric properties of the as-prepared TiO2 films will be evaluated by using the TiO2 films as the DSSC anode. The relationship between the films structure and the photoelectric properties will be studied. These researches will provide useful theory and practice experiences for the design and preparation of TiO2 films with excellent photoelectric properties.

纳米晶TiO2阳极薄膜中含有大量的表面缺陷和晶界位阻，它们作为复合中心严重地阻碍了光生电子的传输，因此会衰减染料敏化太阳电池的光电性能。而具有旋节分相结构的TiO2薄膜能较好地解决这一难题。该种薄膜具有连续的TiO2骨架结构，不仅比表面积大，而且晶界位阻少，可为电子的传输提供一个良好的通道，进而有效地提高电池的光电性能,采用传统的溶胶－凝胶法却很难获得该种结构。有机单体的聚合反应能产生旋节分相，本研究将借助这一特性制备具有旋节分相结构的TiO2阳极薄膜，目的是通过对薄膜结构的调控实现太阳电池优良的光电性能。将系统研究溶胶组成、聚合条件、薄膜的水解－缩聚反应、薄膜的表面修饰等对薄膜结构的影响规律，建立旋节分相结构与反应条件之间的联系，通过对薄膜中TiO2结构的生长特性研究，揭示其形成机理，进而实现薄膜结构的可控。研究太阳电池的性能及其与薄膜结构之间的关系，最终获得具有优良性能的太阳电池。

本研究针对纳米晶TiO2 阳极薄膜中影响光生电子的传输的关键问题展开，采用聚合诱导相分离法制备了具有旋节分相结构的TiO2 薄膜。该种薄膜具有连续的TiO2 骨架结构，比表面积大、而且晶界位阻少，可为电子的传输提供一个良好的通道，进而有效地提高电池的光电性能。本研究借助有机单体的聚合反应能产生旋节分相这一特点，制备了具有旋节分相结构的TiO2 阳极薄膜。系统地研究溶胶组成、聚合条件、薄膜的水解－缩聚反应、薄膜的表面修饰等对薄膜结构的影响规律，建立旋节分相结构与反应条件之间的联系，通过对薄膜中TiO2 结构的生长特性研究，揭示了其形成机理，进而实现薄膜结构的可控制备。研究了太阳电池的性能及其与薄膜结构之间的关系，在阳极薄膜厚度为1μm的条件下，最终获得光电转换效率为5.69%的染料敏化太阳电池。在染料敏化太阳电池研究基础上，开展了气相辅助溶液法制备钙钛矿太阳电池研究。相比液相反应，气相反应能有效地避免溶剂化和水解反应，减少由此产生的复生结构，通过调整气相反应条件可对反应速度进行控制，进而获得均匀的薄膜。将系统研究影响钙钛矿薄膜结构的关键因素，阐明钙钛矿薄膜生长机制，实现其结构可控。探明太阳电池的光电性能与薄膜结构之间的关系，揭示电池内部载流子传输影响机制，最高实现了认证效率为19.2%钙钛矿太阳电池。