Theoretical Guided Material and Interface Optimization for High Performance Perovskite/Organic Tandem Solar Cells

Addressing the pressing challenges of rising global energy needs and achieving carbon neutrality to protect the environment necessitates the development of a practical solution. The emergence of solution-processed organic and metal halide perovskite semiconductors, and their resultant solar cells, could potentially instigate a revolution in photovoltaic technology, enabling the delivery of scalable, high-performance solar cells for sustainable green energy production. Despite the power conversion efficiencies of both single-junction organic solar cells and perovskite solar cells rapidly reaching over 19% and 26% respectively, their maximum efficiency is confined to around 30% as per the Shockley-Queisser model for single-junction devices. However, by fabricating a multi-junction device with multiple light absorbers possessing significantly varied bandgaps, the efficiency of solar cells could potentially be augmented to over 40%.<br/>In this talk, I will introduce high-performance monolithic perovskite/organic tandem solar cells with PCE&gt;26%. These encompass a wide bandgap perovskite front cell and a narrow bandgap organic rear cell connected via a recombination junction. We have selected wide bandgap perovskite solar cells for the front cell due to their robust absorption for visible light, minimal voltage loss, and superior photoresponse. Meanwhile, narrow bandgap organic solar cells could potentially offer superior near-infrared absorption tunability and stability, making them ideal candidates for the rear cell of the tandem cells. To demonstrate the potential of perovskite/organic tandem solar cells, we employ an integrated strategy that combines materials, interface, optical, and process engineering.