Observation of electron–phonon coupling and linear dichroism in PL spectra of ultra-small CsPbBr_(3) nanoparticle solution  

作　　者：Chengqiang Wang Tao Song Pingyuan Yan Shu Hu Chenhong Xiang Zihan Wu Heng Li Haibin Zhao Lili Han Chuanxiang Sheng 

机构地区：[1]State Key Laboratory of Photovoltaic Science and Technology,Department of Optical Science and Engineering,School of Information Science and Technology,Fudan University,Shanghai 200433,China [2]College of Chemistry and Chemical Engineering,Key Laboratory of Special Function Materials and Structure Design,Ministry of Education,Lanzhou University,Lanzhou 730000,China [3]School of Electronic and Optical Engineering,Nanjing University of Science and Technology,Nanjing 210094,China [4]State Key Laboratory of Structural Chemistry,Fujian Institute of Research on the Structure of Matter,Chinese Academy of Sciences,Fuzhou 350002,China

出　　处：《eScience》2023年第6期51-57,共7页电化学与能源科学（英文）

基　　金：supported by startup funding at Fudan University,National Natural Science Foundation of China (Nos.62074079,61774039);large instrument equipment open fund of Nanjing University of Science and Technology.

摘　　要：Blue-emission(~480 nm)CsPbBr_(3) nanoparticles with ultra-small size(~2.1 nm)are synthesized using the liquid nitrogen freezing with the ligand of dodecylbenzene sulfonic acid(DBSA).Asymmetric narrow emissions at the low energy side,with the full width at half-maximum of~20 nm,are observed in solution and film at room temperature.The spectral asymmetry is mainly ascribed to phonon vibronic replica with averaged phonon energy of~40 meV.Moreover,exciting this CsPbBr_(3) nanoparticles solution using linearly polarized 6 ns pulsed laser at 355 nm,we observe polarized emission with polarization degree(P_(PL))of~7%,and P_(PL) decreases more than 20%in the vibronic progression.However,the P_(PL) goes to zero in frozen solutions as well as in films.Thus we speculate the polarized emission is due to the photoinduced re-alignment of nanoparticles,and the diminished P_(PL) at the phonon side band may be due to the non-adiabatic electronic-to-vibronic transitions.The novel phenomena from the ultra-small CsPbBr_(3) nanoparticle demonstrated in this work may provide fundamental insights into its photophysics with direct implications for optoelectronics.

关 键 词：CsPbBr_(3) Phonon vibronic replicas Polarized Ultra-small Electron–phonon coupling 

分 类 号：TB383[一般工业技术—材料科学与工程]