Methylammonium-free, high-efficiency, and stable all-perovskite tandem solar cells enabled by multifunctional rubidium acetate

All-perovskite tandem solar cells (APTSCs) offer the potential to surpass the Shockley-Queisser limit of single-junction solar cells at low cost. However, high-performance APTSCs contain unstable methylammonium (MA) cation in the tin-lead (Sn-Pb) narrow bandgap subcells. Currently, MA-free Sn-Pb perovskite solar cells (PSCs) show lower performance compared with their MA-containing counterparts. This is due to the high trap density associated with Sn2+ oxidation, which is exacerbated by the rapid crystallization of MA-free Sn-containing perovskite. Here, a multifunctional additive rubidium acetate (RbAC) is proposed to passivate Sn-Pb perovskite. We find that RbAC can suppress Sn2+ oxidation, alleviate…

• NN
  National Natural Science Foundation of China

  Awards: 52302333, 52202293, 52302327, 52330004
• FR
  Fundamental Research Funds for the Central Universities

  Awards: 2023IVB009, 2023IVA075
• BA
  Basic and Applied Basic Research Foundation of Guangdong Province

  Award: 2023A1515012788