Fig. 3: Uniform and spectrally tuneable heterophase films.
From: Nanoscale heterophase regulation enables sunlight-like full-spectrum white electroluminescence
a–c Hyperspectral images of α-CsPbI3 and α-CsPb(I/Cl)3 QDs film (a), the γ/δ-CsPbI3 and γ/δ-CsPb(I/Cl)3 film ranging from 660 to 700 nm (b) and the γ/δ-CsPbI3 and γ/δ-CsPb(I/Cl)3 film ranging from 400 to 600 nm (c), the scalebar is 2 μm. Spatially resolved confocal fluorescence-lifetime imaging microscopy of the heterophase film (> 600 nm) (d) and the heterophase film (<600 nm) (e), the scalebar is 2 μm. f PL lifetime of the γ/δ-CsPbI3 and γ/δ-CsPb(I/Cl)3 film. The temperature-dependent PL spectroscopy of α-CsPbI3 and α-CsPb(I/Cl)3 QDs film (g), γ/δ-CsPbI3 film (h) and γ/δ-CsPb(I/Cl)3 film (i). Early-time transient absorption spectra measurements of perovskite thin films (0–2 ps average) with different annealing times under 400 nm pump (j) and 560 nm pump (k). l Schematic of PL phenomena of band-to-band luminescence from γ-CsPbI3 and STE luminescence from δ-CsPbI3.
