Research progress of perovskite-based triple-junction tandem solar cells

Abstract

The energy conversion efficiency of single-junction solar cells is limited by the Shockley-Queisser theory and the most effective strategy to break through this limit is to fabricate multi-junction tandem solar cells. Perovskite materials offer a continuously tunable energy band structure, which provides a new option for light-absorbing materials in multi-junction tandem cells. In the field of perovskite-based multi-junction tandem solar cells, triple-junction tandem solar cells demonstrating immense potential. The present paper introduces the configuration of triple-junction solar cells and addresses three scientific challenges. 1）Ensuring energy level alignment among sub-cells is a critical concern for three-junction batteries. Specifically, the top wide-band gap sub-cell must possess a band gap ranging from 1.8eV to 2.2eV; however, current perovskite material systems with wide-band gaps exhibit certain defects. 2） attaining current matching in multi-junction tandem solar cells while optimizing the absorption layer and minimizing parasitic absorption is essential to maximize solar cell current output. 3） The functional layers of multi-junction tandem solar cells are sequentially stacked using different deposition methods, thereby imposing higher compatibility requirements on the intermediate interconnect layer. Subsequently, the research progress of perovskite-based triple-junction tandem solar cells is then presented, encompassing perovskite/perovskite/silicon tandem solar cells, perovskite/perovskite/organic tandem solar cells, and all-perovskite tandem solar cells. Their respective highest efficiencies are 19.4%, 23.87%, and 27.1%. Finally, this paper examines the research direction for further enhancing the performance of triple-junction solar cells. In addition to augmenting energy conversion efficiency, perovskite-based solar cells must address stability issues in order to achieve future commercialization, thereby offering guidance for the development of efficient triple-junction cells.