Perovskite-based tandem solar cells gallop ahead

Perovskite-based tandem cells as clean photovoltaic conversion devices drive the transition to decarbonized energy. Recently in Nature, Tan and co-workers report a certified efficiency of 26.4%, a record-setting efficiency in all-perovskite tandem solar cells. High photocurrent density is achieved by ammonium cation passivation, addressing the short carrier diffusion length in thick mixed Pb-Sn narrow-bandgap subcell.