Tandem Architecture of Perovskite and Cu(In,Ga)(S,Se)2 Created by Solution Processes for Solar Cells

Integrating tandem solar cell architectures into devices can improve their power conversion efficiency (PCE) by overcoming the limited incident light absorption range of a single absorber and reducing the thermalization loss. Here, fabricated tandem solar cells are successfully fabricated employing different absorber materials, in this case perovskite and Cu(In,Ga)(S,Se)2 (CIGS) as top and bottom cells, respectively. For cost effectiveness most tandem device manufacturing processes are achieved by solution‐based methods, which even provide the electrode layers. Using such a process to create a tandem device, a PCE of 8.34% for the semitransparent perovskite top solar cell and 2.48% for the CIGS bottom solar cell is obtained, resulting in an overall efficiency of 10.82% for the four‐terminal tandem device. This result highlights the potential of this solution‐based tandem configuration as a way to facilitate the creation of simple and inexpensive efficient light‐utilizing solar cell devices.