逐层沉积的高性能全聚合物太阳能电池

全聚合物太阳能电池是一种活性层由聚合物给体和聚合物受体组成的光伏器件。相比于本体异质结的全聚合物太阳能电池，逐层沉积可以独立调控给体层和受体层的形貌提升器件性能，同时其制备的全聚合物太阳能电池的器件稳定性更好。但是，与本体异质结的全聚合物太阳能电池相比，逐层沉积的全聚合物太阳能电池的能量转换效率仍有较大差距。

基于此，采用聚合物给体PM6和聚合物受体L15作为活性层材料，应用逐层沉积工艺，结合氯苯/氯仿非正交溶剂和添加剂的协同作用，深入、全面调控给体和受体的垂直梯度分布和薄膜形貌，获得了效率高达16.15%的全聚合物太阳能电池，打破了同期全聚合物太阳能电池的最高效率记录。多种经典全聚合物材料体系证实了该逐层沉积工艺对于提升全聚合物太阳能电池效率具有普适性。

为进一步提升能量转换效率，采用硒原子策略优化受体L15，构筑了高迁移率、更窄带隙的受体材料Y5-BSeI。经过系统的器件优化，采用氯苯/氯仿非正交溶剂制备的基于PM6:Y5-BSeI材料体系的逐层沉积的全聚合物太阳能电池实现了17%的效率，高于相应的本体异质结的全聚合物太阳能电池（16.25%）。上个逐层沉积工艺的普适性也得到了很好的验证。

由于非正交溶剂的相似溶解性，上述逐层沉积工艺中的薄膜损失严重。相比于PM6，受体Y5-BSeI溶于更多有机溶剂，因此筛选了六组正交溶剂制备逐层沉积的全聚合物太阳能电池。最终，氯苯/甲苯正交溶剂所制备的逐层沉积的全聚合物太阳能电池获得了16.36%的效率。而且，该器件的光、热稳定性均优于氯苯/氯仿非正交溶剂所制备的逐层沉积的全聚合物太阳能电池，兼顾了效率和器件稳定性。

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