Fig. 1. Multilayer structure of PEO∶MAPbBr3 device. (a) Configuration; (b) energy-level diagram

Fig. 2. SEM images of PEO∶MAPbBr3 samples with different PCH3NH3Br∶PPbBr2. (a) 1.05∶1; (b) 1.5∶1; (c) 2∶1; (d) 3∶1

Fig. 3. XRD patterns and EDS image of the samples. (a) XRD patterns for of the samples with PCH3NH3Br∶PPbBr2; (b) EDS image for the PCH3NH3Br∶PPbBr2=1.5∶1 sample

Fig. 4. SEM images of PEO∶MAPbBr3 samples with different PPEO∶PMAPbBr3 and PAN∶MAPbBr3 sample. (a) 0.25∶1; (b) 0.5∶1; (c) 0.75∶1; (d) 1∶1; (e) PPAN∶PMAPbBr3=0.5∶1

Fig. 5. XRD patterns of PEO∶MAPbBr3 samples with different PEO contents and PAN∶MAPbBr3 sample with PPAN∶PMAPbBr3=0.5∶1

Fig. 6. PL spectra of PEO∶MAPbBr3 samples with different PEO contents and PAN∶MAPbBr3 sample with PPAN∶PMAPbBr3=0.5∶1

Fig. 7. V-I-L and LE-I characteristic curves of A-H devices and luminescence spectra of device C. (a) (c) V-I-L characteristic curves and (b) (d) LE-I characteristic curves of A-D and E-H devices; (e) electroluminescence spectra of device C at different voltages, inset is photograph of device C

Fig. 8. Energy-level diagram and voltage-current characteristics of H-only and E-only devices based on PEO and PAN. (a) Energy-level diagram; (b) voltage-current characteristics