Chen Xian-Min, Ye Yong-Chun, Feng Shi-Chi, Lv Bing-Hao, Wang Jiang-Ying, Tang Jian-Xin, Dou Wei-Dong
College of Materials and Chemistry, China Jiliang University, Hangzhou, Zhejiang, 310018, China.
Laboratory of Low-dimensional Carbon Materials and Department of Physics, Shaoxing University, Shaoxing, Zhejiang, 312000, China.
Small. 2024 Sep;20(38):e2401256. doi: 10.1002/smll.202401256. Epub 2024 May 16.
Nickel oxide (NiO) is a promising hole transport layer (HTL) to fabricate efficient and large-scale inverted perovskite solar cells (PSCs) due to its low cost and superior chemical stability. However, inverted PSCs based on NiO are still lagging behind that of other HTL because of the poor quality of buried interface contact. Herein, a bidentate ligand, 4,6-bis (diphenylphosphino) phenoxazine (2DPP), is used to regulate the NiO surface and perovskite buried interface. The diphosphine Lewis base in the 2DPP molecule can coordinate both with NiO and lead ions at NiO/perovskite interface, leading to high-quality perovskite films with minimized defects. It is found that the inverted PSCs with 2DPP-modified buried interface exhibit double advantages of being both fast charge extraction and reduced nonradiative recombination, which is a combination of multiple factors including favorable energetic alignment, improved interface contact and strong binding between NiO/2DPP and perovskite. The optimal PSC based on 2DPP modification yields a champion power conversion efficiency (PCE) of 21.9%. The unencapsulated PSC maintains above 75% of its initial PCE in the air with a relative humidity (RH) of 30-40% for 1000 h.
氧化镍（NiO）因其低成本和优异的化学稳定性，是制造高效大规模倒置钙钛矿太阳能电池（PSC）的一种很有前景的空穴传输层（HTL）。然而，由于掩埋界面接触质量差，基于NiO的倒置PSC仍落后于其他HTL。在此，一种双齿配体4,6-双（二苯基膦基）吩恶嗪（2DPP）被用于调控NiO表面和钙钛矿掩埋界面。2DPP分子中的二膦路易斯碱能与NiO以及NiO/钙钛矿界面处的铅离子配位，从而得到缺陷最小化的高质量钙钛矿薄膜。研究发现，具有2DPP修饰掩埋界面的倒置PSC展现出快速电荷提取和减少非辐射复合的双重优势，这是多种因素的综合结果，包括有利的能量排列、改善的界面接触以及NiO/2DPP与钙钛矿之间的强结合。基于2DPP修饰的最优PSC的冠军功率转换效率（PCE）为21.9%。未封装的PSC在相对湿度（RH）为30 - 40%的空气中1000小时内保持其初始PCE的75%以上。
