Kayesh Md Emrul, Karim Md Abdul, He Yulu, Shirai Yasuhiro, Yanagida Masatoshi, Islam Ashraful
Photovoltaic Materials Group, Center for Green Research on Energy and Environmental Materials, National Institute for Materials Science (NIMS), 1-2-1 Sengen, Tsukuba, Ibaraki, 305-0047, Japan.
Photovoltaic Materials Group, Center for Green Research on Energy and Environmental Materials, National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba, 305-0044, Japan.
Small. 2024 Oct;20(43):e2402896. doi: 10.1002/smll.202402896. Epub 2024 Jun 19.
Developing high-performance and stable Sn-based perovskite solar cells (PSCs) is difficult due to the inherent tendency of Sn oxidation and, the huge energy mismatch between perovskite and Phenyl-C61-butyric acid methyl ester (PCBM), a frequently employed electron transport layer (ETL). This study demonstrates that perovskite surface defects can be passivated and PCBM's electrical properties improved by doping n-type polymer N2200 into PCBM. The doping of PCBM with N2200 results in enhanced band alignment and improved electrical properties of PCBM. The presence of electron-donating atoms such as S, and O in N2200, effectively coordinates with free Sn to prevent further oxidation. The doping of PCBM with N2200 offers a reduced conduction band offset (from 0.38 to 0.21 eV) at the interface between the ETL and perovskite. As a result, the N2200 doped PCBM-based PSCs show an enhanced open circuit voltage of 0.79 V with impressive power conversion efficiency (PCE) of 12.98% (certified PCE 11.95%). Significantly, the N2200 doped PCBM-based PSCs exhibited exceptional stability and retained above 90% of their initial PCE when subjected to continuous illumination at maximum power point tracking for 1000 h under one sun.
由于锡具有氧化的固有倾向，且钙钛矿与常用的电子传输层（ETL）苯基-C61-丁酸甲酯（PCBM）之间存在巨大的能量失配，因此开发高性能且稳定的锡基钙钛矿太阳能电池（PSC）具有一定难度。本研究表明，通过将n型聚合物N2200掺杂到PCBM中，可以钝化钙钛矿表面缺陷并改善PCBM的电学性能。N2200对PCBM的掺杂导致能带排列增强以及PCBM电学性能的改善。N2200中存在的供电子原子如S和O，能有效地与游离的Sn配位以防止进一步氧化。N2200对PCBM的掺杂使ETL与钙钛矿界面处的导带偏移减小（从0.38 eV降至0.21 eV）。结果，基于N2200掺杂PCBM的PSC显示出0.79 V的增强开路电压，功率转换效率（PCE）达到12.98%（认证PCE为11.95%）令人印象深刻。值得注意的是，基于N2200掺杂PCBM的PSC表现出卓越的稳定性，在一个太阳光照下最大功率点跟踪连续照射1000小时后，仍保留其初始PCE的90%以上。
