CsPbBr₃/CsCaAl₂O₄:Nd,Er Nanoriveted Structure Perovskites with Long Afterglow Dual-Wavelength Emission for Flexible Photoelectric Devices

Lead halide perovskites have garnered widespread attention because of their excellent photoelectric and photonic properties. However, their material fabrications and optoelectronic applications are hindered by low stability. Nanoriveted structure perovskites with high stability and long afterglow dual-wavelength emission are synthesized using a shared ion strategy of perovskites and phosphors. The CsPbBr 3 /CsCaAl 2 O 4:Nd,Er nanoriveted structure perovskites exhibit dual-wavelength emission of blue and green during photoexcitation, as well as a prolonged afterglow. The fabricated flexible electroluminescent devices have spectrally tunable and dual-wavelength emissions even at 60° bending. Because the CsPbBr 3 quantum dots (QDs) capture the photon emitted from Er element, the electroluminescent devices retain observable dual-wavelength emissions and high synchronization in their afterglow, which decays after the removal of power. The CsPbBr 3 /CsCaAl 2 O 4:Nd,Er nanoriveted structure perovskites can also be used as the light-emitting downshift layers to improve the performance of photovoltaic modules in photovoltaic devices. At cryogenic temperatures, the temperature-dependent photoluminescence spectra test reveals the energy transfer between CsPbBr 3 QDs and CsCaAl 2 O 4:Nd,Er (contradicts the energy transfer in the afterglow state). These discoveries overcome the limitations of conventional afterglow phosphors, provide new applications for long afterglow materials, and introduce an innovative approach to energy conservation.