Opportunities and Challenges for Emerging Inorganic Chalcogenide-Silicon Tandem Solar Cells

This review highlights the promise of emerging inorganic chalcogenide-silicon (Si) tandem solar cells (TSCs) to overcome the power conversion efficiency (PCE) and long-term stability limitations of single-junction solar cells, advancing them toward early commercialization. First, we cover the fundamentals of TSCs, including basic concepts, design considerations, and key requirements. The unique optoelectronic properties of proven and emerging chalcogenide absorber materials are then thoroughly examined to evaluate whether they are suitable candidates for the top cell in tandem configurations. Furthermore, we highlight the critical factors that limit PCE when compared to III-V-, Si-, and perovskite-based tandem and single-junction solar cells. In light of limitations, we discuss the challenges and solutions for the fabrication process, device performance, long-term stability, and outdoor testing of chalcogenide-Si TSCs. Finally, we provide perspectives on future research directions and potential pathways for the early commercialization of these emerging inorganic chalcogenide-Si tandem technologies.