Fig. 2: Optoelectronic properties of RDP films.

a PL spectra of the RDP films. Inset shows the PLQYs and photographs under ultraviolet illumination of the RDP films. b Arrhenius plots of the characteristic frequencies to extract the defect activation energy (Ea) for the RDP films. c Core-level XPS spectra of Pb 4 f of the RDP films. d Integration of the temperature-dependent PL intensity of the RDP films and fitting curves for Eb