Asymmetric Spacer in Dion–Jacobson Halide Perovskites Induces Staggered Alignment to Direct Out-of-Plane Carrier Transport and Enhance Ambient Stability Simultaneously
Dion–Jacobson (DJ)-type 2D halide perovskites present superior environmental stability and a narrower bandgap, yet a contradiction between charge transport and stability remains to be resolved. Herein, it is shown that both symmetry and substitution of the organic spacer in DJ perovskites synergistically direct the narrow interlayer spacing, staggered spacer alignment, and regular phase arrangemen