基于减反增透型导电薄膜的钙钛矿太阳能电池的制备及性能研究

In recent years, perovskite solar cell has been rapidly developed and its power conversion efficiencies (PCEs) reached up to 20.2%. In recent years, perovskite solar cell has been rapidly developed and its power conversion efficiencies (PCEs) reached up to 20.2%. Traditional electron transport layer fabricated by TiO2 materials has high interface reflectivity, which makes large portion of incident light not penetrate electron transport layer and decreases light absorption of perovskite. To further increase the PCEs of perovskite solar cell, antireflective conductive thin-film will be designed to reduce interface reflectivity and increase light absorption by perovskite materials, which has great potential in perovskite solar cell. To further increase the PCEs of perovskite solar cell, antireflective conductive thin-film will be designed to reduce interface reflectivity and increase light absorption by perovskite materials, which has great potential in perovskite solar cell. In this research, low refractive index oxide nanomaterials with appropriate morphology and size distribution will be synthesized by hydrothermal or sol-gel method to fabricate thin film as electron transport layer. The thin film would show broadband antireflectivity in the wavelength range of 400-800 nm. The effects of thin-film morphology, optical and electrical properties on PCEs of the perovskite solar cell will be studied. Meanwhile， the mechanism of charge carrier transportation of within such thin-film will be explored to fulfill the preparation of high-efficiency perovskite solar cells.

近几年，钙钛矿太阳能电池经过高速发展，目前最高转化效率已经达到20.2%。常用的钙钛矿电池电子传输层材料主要是TiO2导电薄膜，但是由于存在界面高反射，导致大部分入射光不能穿透电子传输层被钙钛矿吸光层吸收。为了解决这一问题，申请人设计构筑减反增透的导电薄膜，减小界面光反射带来的损失，提高吸光材料对入射光的利用，从而进一步提高钙钛矿太阳能电池的效率，预期减反增透型导电薄膜在钙钛矿太阳能电池中具有重要的应用潜力。本项目在前期研究基础上采用以水热法或溶胶凝胶法制备合适形貌以及尺寸的低折射率氧化物纳米材料，并构筑薄膜作为电子传输层，调控使得薄膜在400-800 nm波段范围内具有宽光谱的减反增透性能。综合研究薄膜形貌结构、光学性能（反射率，透光率）和电学性能（导电率, 载流子浓度）对钙钛矿电池光电转换性能的影响。并研究载流子在减反增透的导电薄膜中的传输机制，实现高效钙钛矿太阳能电池的制备。

近年来，钙钛矿太阳能电池经过高速发展，转化效率已经接近于商业化的硅基太阳能电池。常用的钙钛矿电池用TiO2作为电极修饰层，但是由于TiO2界面的高反射，导致大部分入射光不能穿透电子传输层被钙钛矿吸光层吸收，影响太阳能电池的效率。在本项目的支持下，我们对这一问题进行了深入的研究，获得主要成果如下：(1) 我们通过一系列方法设计并制备了高透明的导电薄膜，有效地降低界面反射，提高器件的光伏性能；(2) 利用VOx高透明薄膜，设计制备梯度异质结，作为钙钛矿电池的空穴传输层，有效地提高了器件的光伏性能及稳定性；(3) p型半导体材料掺杂或修饰PEDOT:PSS，调控透光性质，作为空穴传输层，有效地提高了结晶质量及晶体尺寸，提高了光电转换效率；(4) 研究了钙钛矿电池的激子动力学过程，提出了钙钛矿电池光伏性能改进的机理。相关研究成果已经发表SCI论文10篇，其中影响因子大于3.0的9篇，申请专利3项，培养硕士5名。