Researchers from Nanjing University, University of Victoria and Australian National University have achieved a high conversion efficiency of 24.5% on large-size all-perovskite tandem solar cells. The result, which the team states is a new world record for the efficiency of all-perovskite tandem solar cells, has reporetdly been confirmed by an international third-party testing institute.
When a lead-tin perovskite is used instead of silicon as the narrow band gap cell in all-perovskite tandem solar cells, the result is often low film quality and device efficiency due to nonuniform nucleation and fast crystallization. In this recent work, the team shows that aminoacetamide hydrochloride can strongly coordinate the precursor components in solution, which homogenizes the crystallization process and also passivates the buried perovskite interface. The authors achieved a certified power conversion efficiency of 24.5% for a 20-square-centimeter module made by blade-coating the layers.
The team used the aminoacetamide hydrochloride dopant to homogenize perovskite crystallization and to extend the processing window for blade-coating Pb-Sn perovskite films, as well as selectively passivate defects at the buried perovskite interface.
The resulting all-perovskite tandem solar module exhibited a certified power conversion efficiency of 24.5% with an aperture area of 20.25 square centimeteIn