Improving persistent luminescence in pressure-tuned CsPbBr3 nanocrystals by Ce3+ doping

Abstract

The pressure-dependent photoluminescence kinetics of CsPbBr₃:Ce quantum dots was investigated by steady-state and time-resolved photoluminescence spectroscopy. Here, we propose a novel strategy to improve the persistent luminescence of CsPbBr₃ quantum dots under high pressure through doping of Ce³⁺ ions. Under high pressure, the peak intensity and energy of CsPbBr₃:Ce quantum dots decreased more slowly than those of CsPbBr₃ quantum dots, which is manifested by pressure coefficient reductions of 0.08 a.u. GPa⁻¹ and 0.012 eV GPa⁻¹, respectively. The time-resolved photoluminescence measurements revealed that Ce³⁺-doping can significantly modulate the photoluminescence kinetics to shorten the lifetimes of CsPbBr₃ quantum dots with increasing pressure. These phenomena were absolutely different from those observed in CsPbBr₃ quantum dots. These findings will be useful for broadening the application of optical devices based on all-inorganic perovskite materials under high pressure.