期刊
JOURNAL OF PHYSICAL CHEMISTRY C
卷 125, 期 9, 页码 5278-5287出版社
AMER CHEMICAL SOC
DOI: 10.1021/acs.jpcc.0c08995
关键词
-
资金
- Youth Project of National Natural Science Foundation [11804086]
- Science Fund for Distinguished Young Scholars of Heilongjiang University [JCL201702]
- Basic Scientific Research Business Expenses of Heilongjiang Province (Heilongjiang University Special Fund Project) [KJCX201927]
- Natural Science Foundation of Heilongjiang Province [LH2020A021]
- Youth Science and Technology Innovation Team Project of Heilongjiang Province [2018-KYYWF-1593]
Metal halide perovskites, such as CsPbX3 nanocrystals, exhibit excellent emission and charge-transfer performance due to the quantum effect. By studying their transient absorption spectra, researchers observed the emergence of biexciton states with increasing excitation power, affecting the binding energy of the biexcitons.
Metal halide perovskites are affected by the quantum effect, their size is equal to the Bohr radius of the material, and they exhibit excellent emission performance and charge-transfer performance. We have synthesized CsPbX3 (X = Cl/Br, Br, Br/I) monodisperse nanocrystals (NCs) by a simple heat injection method. The band gap energy and emission wavelength can be changed by adjusting the composition of nanocrystals. CsPbX3 NCs have an emission linewidth of 18-29 nm, a photoluminescence lifetime of 5.7-20.8 ns, and a fast carriertransfer rate. In this paper, the transient absorption (TA) spectra of CsPbX3 NCs were studied by a femtosecond laser. The carrier dynamics is studied by changing the excitation power and delay time. The experimental results show that the bleaching signal of the TA spectrum has a red shift of 5-12 nm initially and then remains unchanged. With an increase of excitation power, the bleaching signal also shows obvious fast decay components, indicating the emergence of biexciton states. In the TA spectrum, the corresponding wavelengths are obtained from the bleaching signals of single and biexciton states, and then, the binding energy of biexciton in the range of 21.7-61.2 meV is calculated according to the optical quantum energy formula.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据