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.