Interfacial Toughening for High-Efficiency Perovskite Solar Modules

The distinctive benefits of perovskite solar cells, such as their lightweight nature, high flexibility, and ease of deformation, have garnered significant interest. These characteristics make them well-suited for use in portable electronic devices. Nevertheless, a significant efficiency gap exists between laboratory-based small cells and industrial-oriented large-scale modules. One of the primary reasons for the efficiency losses is the limited adhesion at the brittle interface between the perovskite layer and the hole-transport layer. Herein, potassium acetate is selected to tailor the interface of the perovskite/hole-transport layer. Different from the potassium acetate treatment layer located underneath the perovskite changed perovskite orientations, the presence of potassium acetate between the perovskite and hole-transport layer has the potential to enhance the p-type perovskite interface. Furthermore, the strengthen of the interface contact may be verified by the utilization of KPFM and DFT calculations. As result, the charge separation is accelerated associated with the substantial enhancement in Voc from 1.118 V to 1.139 V. The power conversion efficiency of the solar cell has been enhanced from 23.76% to 24.81%. Additionally, the perovskite solar module exhibits little loss, with an efficiency of 21.13% with an aperture area of 29.0 cm2.