Huang Tengzuo, Wu Chunyan, Yang Jinpeng, Hu Pengyu, Qian Lei, Sun Tao, Xiang Chaoyu
Laboratory of Advanced Nano-Optoelectronic Materials and Devices, Qianwan Institute of CNITECH, Ningbo, Zhejiang 315336, P. R. China.
International Joint Research Center of China for Optoelectronic and Energy Materials, Energy Research Institute, Yunnan University, Kunming, Yunnan 650091, P. R. China.
ACS Appl Mater Interfaces. 2024 Jan 10;16(1):915-923. doi: 10.1021/acsami.3c16599. Epub 2023 Dec 25.
The interface loss between the active layer and the hole transport layer (HTL) of lead sulfide colloidal quantum dot (PbS-CQD) solar cells is a significant factor influencing the efficiency improvement of PbS colloidal quantum dot solar cells (PbS-CQDSCs). Currently, the most advanced solar cells adopt organic P-type HTLs (PbS-EDT) via solid-state ligand exchange with 1,2-ethanedithiol (EDT) on the CQD top active layer. However, EDT is unable to altogether remove the initial ligand oleic acid from the quantum dot surface, and its high reactivity leads to cracks in the HTL film caused by volume contractions, which inevitably results in significant loss. These flaws prompted this research to develop a method involving hybrid organic ligand exchange using 3-mercaptopropionic acid (MPA) and 1,2-EDT (PbS-Hybrid) to overcome these drawbacks of loss. The results indicated that the new exchange strategy improved the quality of the HTL film and benefited from the enhanced passivation of the quantum dot surface and better alignment of energy levels, and the average of PbS-Hybrid devices is increased by approximately 25 mV compared to control devices. With the enhanced , the average power conversion efficiency (PCE) of the devices is improved by 10%, with the highest PCE reaching 13.24%.
硫化铅胶体量子点（PbS-CQD）太阳能电池的活性层与空穴传输层（HTL）之间的界面损失是影响PbS胶体量子点太阳能电池（PbS-CQDSCs）效率提升的一个重要因素。目前，最先进的太阳能电池通过在CQD顶部活性层上与1,2-乙二硫醇（EDT）进行固态配体交换来采用有机P型HTL（PbS-EDT）。然而，EDT无法完全去除量子点表面的初始配体油酸，并且其高反应性会导致HTL膜因体积收缩而产生裂缝，这不可避免地会导致显著损失。这些缺陷促使本研究开发一种涉及使用3-巯基丙酸（MPA）和1,2-EDT进行混合有机配体交换的方法（PbS-混合），以克服这些损失的缺点。结果表明，新的交换策略提高了HTL膜的质量，并受益于量子点表面钝化的增强和能级的更好对齐，与对照器件相比，PbS-混合器件的平均 增加了约25 mV。随着 的提高，器件的平均功率转换效率（PCE）提高了10%，最高PCE达到13.24%。
