How to minimize voltage and fill factor losses to achieve over 20% efficiency lead chalcogenide quantum dot solar cells: Strategies expected through numerical simulation. (1st July 2023)

• Record Type: Journal Article
• Authors: Wang, Dandan; Li, Yusheng; Yang, Yongge; Hayase, Shuzi; Wu, Haifeng; Wang, Ruixiang; Ding, Chao; Shen, Qing
• Is Part Of: Applied energy. Volume 341(2023)
• Publication Date: 2023-07-01
• Subjects: Lead chalcogenide colloidal quantum dot solar cells -- Non-radiative recombination -- Internal resistances -- Open-circuit voltage -- Fill factor; Power (Mechanics) -- Periodicals; Energy conservation -- Periodicals; Energy conversion -- Periodicals; 621.042
• DOI: 10.1016/j.apenergy.2023.121124
• Languages: English
• ISSNs: 0306-2619

Abstract

Abstract: Lead chalcogenide colloidal quantum dot solar cells (CQDSCs) have the potential to revolutionize the field of light-to-electricity conversion with their exceptional optoelectronic properties. Unfortunately, realizing their full potential has been hindered by persistent and poorly understood limitations in fill factor (FF) and open-circuit voltage ( V oc ) losses. In this study, we performed a systematic numerical analysis of practical PbS CQDSCs to identify the root causes of FF and V oc losses in the current development stage, and to provide a clear and feasible roadmap for achieving a PCE of more than 20% in future development stages. Our analysis revealed that the highly effective route for enhancing the current 10% device is to initially modify the internal resistances, resulting in a significant reduction in FF losses to 15%, followed by systematic optimization of surface recombination velocities in the absorber layer and the absorber/hole transfer layer (HTL) interface, which can generate a V oc improvement of 3.76%, ultimately leading to a near-15% PCE. To further elevate PCE to unprecedented heights, we identified the precise regulation of surface excess charge densities at the absorber/HTL interface and the HTL/back contact interface as critical factors. By finely tuning these performance-limiting factors, we demonstrated the feasibility of achieving over 20% PCE, with minimal V oc loss of 318.10 mV and almost negligible FF loss of 6.08% in PbS CQDSCs. Our investigation provides crucial insights into the causes of FF and V oc losses in PbS CQDSCs and offers a clear pathway for future progress in this rapidly evolving field.