Weak Fermi level pinning and low barrier interfacial contact: 2D lead-free perovskites on multilayer GaN

GaN as an electron transport layer for the CsSrI 3 perovskite achieves low loss contact. The Ba–CsSrI 3 /GaN interface effectively overcomes both FLP and high barriers, exhibiting an interface electron transfer conductivity of up to 7.79 × 10 3 S cm −1 .