{"title":"Real-Time Tracking of Emitter Generation in Zero-Dimensional Perovskite","authors":"Ruijia Sun, Nianqiao Liu, Wei Zheng, Ning-bo Li, Huqiang Lian, Hong Liu, Yuhai Zhang","doi":"10.2139/ssrn.3661952","DOIUrl":null,"url":null,"abstract":"The photoluminescence of green-emitting Cs4PbBr6 crystals has shown superior stability over that of standard CsPbBr3 phase towards many harsh conditions, including long-term storage, heat shock, light irradiation, and even multiple solvent rinsing. However, the understanding of its origin remained controversial, partially due to the lack of real-time observation on its initial formation stage. Here, this work reported the direct observation of emitter generation in the crystallization stage. Through the use of a home-made crystal incubator coupled with a fluorescent microscope, both the crystal growth and emitter emergence were tracked in a real-time manner. The emitter distribution was found oriented along c axis and the cooling rate of precursor was found a key factor to manipulate the emitter density, which was reported for the first time to the best of our knowledge. Through an ultra-slow cooling procedure, a full-body emitting crystal of high PL QY up to 83% was obtained. Importantly, the PL QY was found temperature-insensitive in a broad range from 80 K to 300 K despite of strong phonon-electron coupling effect. The lifetime displayed a linear relationship to temperature, which suggested a 2D quantum-well feature of excitons according to Rosales model. This work provided many new evidences and insights into the PL origin of Cs4PbBr6, representing a step forward to approaching the nature of emitters in low dimensional perovskites.","PeriodicalId":9858,"journal":{"name":"Chemical Engineering (Engineering) eJournal","volume":null,"pages":null},"PeriodicalIF":0.0000,"publicationDate":"2020-08-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Chemical Engineering (Engineering) eJournal","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.2139/ssrn.3661952","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 0
Abstract
The photoluminescence of green-emitting Cs4PbBr6 crystals has shown superior stability over that of standard CsPbBr3 phase towards many harsh conditions, including long-term storage, heat shock, light irradiation, and even multiple solvent rinsing. However, the understanding of its origin remained controversial, partially due to the lack of real-time observation on its initial formation stage. Here, this work reported the direct observation of emitter generation in the crystallization stage. Through the use of a home-made crystal incubator coupled with a fluorescent microscope, both the crystal growth and emitter emergence were tracked in a real-time manner. The emitter distribution was found oriented along c axis and the cooling rate of precursor was found a key factor to manipulate the emitter density, which was reported for the first time to the best of our knowledge. Through an ultra-slow cooling procedure, a full-body emitting crystal of high PL QY up to 83% was obtained. Importantly, the PL QY was found temperature-insensitive in a broad range from 80 K to 300 K despite of strong phonon-electron coupling effect. The lifetime displayed a linear relationship to temperature, which suggested a 2D quantum-well feature of excitons according to Rosales model. This work provided many new evidences and insights into the PL origin of Cs4PbBr6, representing a step forward to approaching the nature of emitters in low dimensional perovskites.