Limiting Perovskite Solar Cell Performance by Heterogeneous Carrier Extraction

详细信息    查看全文

• 作者：Dr. Wenming Tian ; Rongrong Cui ; Dr. Jing Leng ; Junxue Liu ; Yajuan Li ; Chunyi Zhao ; Prof. Dr. Jun Zhang ; Prof. Dr. Weiqiao Deng ; Prof. Dr. Tianquan Lian and Prof. Dr. Shengye Jin
• 刊名：Angewandte Chemie
• 出版年：2016
• 出版时间：October 10, 2016
• 年：2016
• 卷：128
• 期：42
• 页码：13261-13265
• 全文大小：1976K
• ISSN：1521-3757

文摘

Although the power conversion efficiency of perovskite solar cells has improved rapidly, a rational path for further improvement remains unclear. The effect of large morphological heterogeneity of polycrystalline perovskite films on their device performance by photoluminescence (PL) microscopy has now been studied. Contrary to the common belief on the deleterious effect of morphological heterogeneity on carrier lifetimes and diffusivities, in neat CH₃NH₃PbI₃(Cl) polycrystalline perovskite films, the local (intra-grain) carrier diffusivities in different grains are all surprisingly high (1.5 to 3.3 cm² s⁻¹; comparable to bulk single-crystals), and the local carrier lifetimes are long (ca. 200 ns) and surprisingly homogenous among grains, and uniform across grain boundary and interior. However, there is a large heterogeneity of carrier extraction efficiency at the perovskite grain–electrode interface. Improving homogeneity at perovskite grain–electrode contacts is thus a promising direction for improving the performance of perovskite thin-film solar cells.