Size Modulation and Heterovalent Doping Facilitated Hybrid Organic and Perovskite Quantum Dot Bulk Heterojunction Solar Cells
Yuhao Li, Shu Zhou, Zhiyu Xiong, Minchao Qin, Kuan Liu, Guilong Cai, Han Wang, Shenghe Zhao, Gang Li, Yao‐Jane Hsu, Jianbin Xu, Xinhui Lu
Abstract
Organic photovoltaics and halide perovskite solar cells are both solution-processable third-generation photovoltaic devices (PVs) attracting enormous research attention. In this study, we demonstrate a hybrid organic and perovskite PV device by mixing all-inorganic CsPbI3 quantum dots (QDs) into the conventional organic bulk heterojunction active layer of PBDB-T:IT-M. It is found that the charge transfer properties between QDs and organic donor/acceptor interfaces can be fine-tuned with the size modulation and the heterovalent bismuth (Bi) doping of perovskite QDs, leading to an increase in open-circuit voltage. In addition, the incorporation of perovskite QDs with different sizes could effectively modify the nanoscale bulk heterojunction morphology toward more efficient charge collection and thus a higher fill factor. The photocurrent of the devices can also be improved through Rayleigh scattering and light absorption of the QDs. As a result, a noticeable enhancement in device performance has been achieved by the PBDB-T:IT-M with 10 nm Bi-doped CsPbI3 QD device. This work provides one feasible route to fine-tune the energy level alignment and nanophase separation by integrating these two promising PV materials.