“…The red shift of PL occurred in MAAc and "L-I" based film may be due to the excess MA + (Figure 2c). [33][34][35][36] Moreover, the PL spectra of LDRP Sn perovskite with different layers (n) and 3D Sn perovskite ( Figure S5, Supporting Information) showed a blue shift of PL peaks from about 990 to 820 nm, corresponding to the phase from 3D to low dimension (LDRP, n = 2, 3, 4, etc.) [33][34][35][36] Moreover, the PL spectra of LDRP Sn perovskite with different layers (n) and 3D Sn perovskite ( Figure S5, Supporting Information) showed a blue shift of PL peaks from about 990 to 820 nm, corresponding to the phase from 3D to low dimension (LDRP, n = 2, 3, 4, etc.)…”