Biexciton Auger recombination in mono-dispersed, quantum-confined CsPbBr3 perovskite nanocrystals obeys universal volume-scaling  

作　　者：Yulu Li Tao Ding Xiao Luo Zongwei Chen Xue Liu Xin Lu Kaifeng Wu 

机构地区：[1]Departmental of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China [2]State Key Laboratory of Molecular Reaction Dynamics and Dynamics Research Center for Energy and Environmental Materials, Dalian Institute oj Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China

出　　处：《Nano Research》2019年第3期619-623,共5页纳米研究（英文版）

基　　金：We gratefully acknowledge financial supports from the Ministry;Science and Technology of China (No. 2018YFA028703);the National Natural Science Foundation of China (No. 21773239).

摘　　要：Auger recombination has been a long?standing obstacle to many prospective applications of colloidal quantum dots (QDs) ranging from lasing, light-emitting diodes to bio-labeling. As such, understanding the physical underpinnings and scaling laws for Auger recombination is essential to these applications. Previous studies of biexciton Auger recombination in various QDs established a universal scaling of biexciton lifetime (rxx) with QD volume (V):τxx =γV. However, recent measurements on perovskite nanocrystals (NCs), an emerging class of enablers for light harvest!ng and emitting applications, showed significant deviations from this universal scaling law, likely because the measured NCs are weakly-confined and also have relatively broad size-distributions. Here we study biexciton Auger recombination in mono-dispersed (size distributions within 1.7%—9.0%), quantunvconfined CsPbBr3 NCs (with confinement energy up to 410 meV) synthesized using a latest approach based on thermodynamic equilibrium control. Our measurements clearly reproduce the volume-scaling of τxx in confined CsPbBb QDs. However, the scaling factor γ(0.085 ± 0.001 ps/nm^3) is one order of magnitude lower than that reported for CdSe and PbSe QDs (1.00 ± 0.05 ps/nm^3), suggest!ng unique mechanisms enhancing Auger recombination rate in perovskite NCs.

关 键 词：PEROVSKITE NANOCRYSTALS AUGER recombination BIEXCITON volume-scaling ultrafast spectroscopy 

分 类 号：O4[理学—物理]