Ka Ibrahima, Asuo Ivy M, Basu Suchismita, Fourmont Paul, Gedamu Dawit M, Pignolet Alain, Cloutier Sylvain G, Nechache Riad
Department of Electrical Engineering, École de Technologie Supérieure, 1100 Notre-Dame Ouest, Montréal, Québec, H3C 1K3, Canada.
Institut National de la Recherche Scientifique INRS-Énergie, Matériaux et Télécommunications, 1650, Blvd. Lionel-Boulet, Varennes, Québec, J3 × 1S2, Canada.
Small. 2018 Sep;14(38):e1802319. doi: 10.1002/smll.201802319. Epub 2018 Aug 24.
The morphology of hybrid organic-inorganic perovskite films is known to strongly affect the performance of perovskite-based solar cells. CH NH PbI Cl (MAPbI Cl ) films have been previously fabricated with 100% surface coverage in glove boxes. In ambient air, fabrication generally relies on solvent engineering to obtain compact films. In contrast, this work explores the potential of altering the perovskites microstructure for solar cell engineering. This work starts with CH NH PbI Cl , films with grain morphology carefully controlled by varying the deposition speed during the spin-coating process to fabricate efficient and partially transparent solar cells. Devices produced with a CH NH PbI Cl film and a compact thick top gold electrode reach a maximum efficiency of 10.2% but display a large photocurrent hysteresis. As it is demonstrated, the introduction of different concentrations of bromide in the precursor solution addresses the hysteresis issues and turns the film morphology into a partially transparent interconnected network of 1D microstructures. This approach leads to semitransparent solar cells with negligible hysteresis and efficiencies up to 7.2%, while allowing average transmission of 17% across the visible spectrum. This work demonstrates that the optimization of the perovskites composition can mitigate the hysteresis effects commonly attributed to the charge trapping within the perovskite film.
众所周知，有机-无机杂化钙钛矿薄膜的形态会强烈影响钙钛矿基太阳能电池的性能。此前已在手套箱中制备出具有100%表面覆盖率的CH₃NH₃PbI₂Cl（MAPbI₂Cl）薄膜。在环境空气中，制备通常依赖于溶剂工程来获得致密薄膜。相比之下，这项工作探索了改变钙钛矿微观结构用于太阳能电池工程的潜力。这项工作从CH₃NH₃PbI₂Cl薄膜开始，通过在旋涂过程中改变沉积速度来仔细控制晶粒形态，以制造高效且部分透明的太阳能电池。用CH₃NH₃PbI₂Cl薄膜和致密厚顶金电极制成的器件达到了10.2%的最大效率，但显示出较大的光电流滞后现象。结果表明，在前体溶液中引入不同浓度的溴化物解决了滞后问题，并将薄膜形态转变为一维微结构的部分透明互连网络。这种方法导致了具有可忽略滞后现象且效率高达7.2%的半透明太阳能电池，同时在可见光谱范围内平均透过率为17%。这项工作表明，钙钛矿成分的优化可以减轻通常归因于钙钛矿薄膜内电荷俘获的滞后效应。
