Tandem solar cells have multiple active layers. The purpose of the tandem solar cell is to make use of the broader part of the electromagnetic spectrum by designing each layer to be sensitive to different

wavelengths. In this way, more efficiency is obtained compared to single-junction solar cells. The layers can be organic, inorganic, or both organic and inorganic (hybrid). Tandem solar cells can be connected in two different ways as parallel and series. In tandem structures (multi-junction), multiple arrangements can be used; each structure has its advantages and disadvantages. Tandem structures are generally classified as two Terminals (2T), three terminals (3T), and four terminals (4T).

We are working following subjects on Tandem solar cells:

• Fabrication and characterization of Si HIT/Perovskite tandem solar cells
• New hole transport materials
• Scale-up and stability of tandem solar cells