Energy Transfer Dynamics of Highly Stable Fe3+ Doped CsPbCl3 Perovskite Nanocrystals with Dual-Color Emission

Developing metal-halide perovskite nanocrystals (NCs) have attracted great interest due to its potential application in optoelectronic devices. Herein, for the first time we report the facile synthesis of Fe3+ doped cesium lead chloride (CsPbCl3) perovskite NCs along with their exciton relaxation dynamics. Efficient energy transfer occurs from host (CsPbCl3) exciton to Fe3+ dopant, leading to pink-colored dual emission consisting of blue from CsPbCl3 exitonic peak (410 nmand red from Fe-dopant state (584 nm).Interestingly, Fe-doping is found to not only enhance the photoluminescence quantum yield from 1.85 to 4.32%, but also improve the homogeneity of size and cubic shape of NCs as observed by electron microscopy. Ultrafast transient absorption studies and global fitting analysis reveal the impact of Fe-doping on the exciton relaxation dynamics, where the efficient energy transfer from host exciton to Fe3+with the lifetime of 135 ps is identified. Another highlighted feature of Fe-doped NCs is its high st...