Figure 1.

(a) Ultraviolet–visible (UV–vis) absorption and photoluminescence (PL) spectra of CsPbI₂Br PNCs obtained under air conditions. (b) Transmission electron microscope (TEM) images of CsPbI₂Br PNCs. (c) Size distribution of CsPbI₂Br PNCs (11.30 nm in size) from TEM images. (d) UV–vis absorption (PL) spectra of CsPbI₂Br thin films obtained under air conditions. (e) SEM images of CsPbI₂Br thin films. (f) Grain size distribution with ∼450 nm CsPbI₂Br thin films. (g) XRD patterns of the CsPbI₂Br PNCs and film counterparts before and after encapsulation upon 405 nm illumination with an average power density of 3180 W cm^–2.