Lewis Base Strategy for Crystallization Control and Buried Interface Passivation on Hydrophobic PTAA Substrate for Efficient Tin–Lead Perovskite and All-Perovskite Tandem Solar Cells

Nonionic PTAA is an ideal substitute for PEDOT:PSS as a hole-selective layer to improve the stability of mixed tin–lead (Sn–Pb) perovskite solar cells (PSCs). However, its hydrophobic nature aggravates the unbalanced crystallization and poor buried contacts of Sn–Pb perovskite films. Here, we report a Lewis base strategy to tackle these issues by introducing 4-bromophenylurea (BPU) or 4-bromophenylthiourea (BPSU) to interact with precursor ingredients to form large clusters, which accelerate nucleation and delay crystal growth as well as suppress buried interfacial nonradiative recombination. Compared to BPU, the more polar BPSU enables stronger interactions with Sn-halides than Pb-halides, resulting in…

• NS
  Natural Science Foundation of Shanghai

  Award: 22ZR1428200
• NN
  National Natural Science Foundation of China

  Award: 52350610264