Dong Wang, Jie Chen, Dongyan Zhang, Dariusz M. Niedzwiedzki, Richard A. Loomis, Bryce Sadtler
{"title":"单粒子光致发光将热处理与铯-溴化铅纳米晶体阱分布的非均质性联系起来","authors":"Dong Wang, Jie Chen, Dongyan Zhang, Dariusz M. Niedzwiedzki, Richard A. Loomis, Bryce Sadtler","doi":"10.1007/s12274-024-6989-3","DOIUrl":null,"url":null,"abstract":"<div><p>Understanding the mechanisms of degradation in lead halide perovskite nanocrystals is critical for their future application in optoelectronic devices. We report single-particle measurements of the photoluminescence from cesium lead bromide nanocrystals coated with a silica shell (CsPbBr<sub>3</sub>@SiO<sub>2</sub>). Through correlative imaging, we quantified changes in the fluorescence intensity trajectories of the same nanocrystals before and after annealing them at different temperatures. We observe that nearly equal numbers of CsPbBr<sub>3</sub>@SiO<sub>2</sub> nanocrystals exhibit an increase versus decrease in the amount of time they spend in an emissive state after annealing at temperatures of 70 and 100 °C. On the other hand, annealing at 120 °C produces a decrease in the on-fraction for most nanocrystals and, correspondingly, a substantial decrease in the photoluminescence intensity for a thin film annealed at this temperature. We attribute the differences in behavior among individual nanocrystals to heterogeneity in the distribution of trap states that are initially present. X-ray photoelectron, time-resolved photoluminescence, and transient absorption spectroscopies performed on thin films of CsPbBr<sub>3</sub>@SiO<sub>2</sub> nanocrystals indicate that thermal annealing heals electron traps by passivating surface Pb ions and simultaneously creates hole traps through the formation of Pb and Cs vacancies. The relative rates of these parallel processes depend on the annealing temperature, which are important to account for when developing passivation strategies for lead halide perovskite nanocrystals in optoelectronic devices that will operate at elevated temperatures.\n</p><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":713,"journal":{"name":"Nano Research","volume":"17 :","pages":"10363 - 10375"},"PeriodicalIF":9.0000,"publicationDate":"2024-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Single-particle photoluminescence connects thermal processing with heterogeneity in the trap distribution of cesium lead bromide nanocrystals\",\"authors\":\"Dong Wang, Jie Chen, Dongyan Zhang, Dariusz M. Niedzwiedzki, Richard A. Loomis, Bryce Sadtler\",\"doi\":\"10.1007/s12274-024-6989-3\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><p>Understanding the mechanisms of degradation in lead halide perovskite nanocrystals is critical for their future application in optoelectronic devices. We report single-particle measurements of the photoluminescence from cesium lead bromide nanocrystals coated with a silica shell (CsPbBr<sub>3</sub>@SiO<sub>2</sub>). Through correlative imaging, we quantified changes in the fluorescence intensity trajectories of the same nanocrystals before and after annealing them at different temperatures. We observe that nearly equal numbers of CsPbBr<sub>3</sub>@SiO<sub>2</sub> nanocrystals exhibit an increase versus decrease in the amount of time they spend in an emissive state after annealing at temperatures of 70 and 100 °C. On the other hand, annealing at 120 °C produces a decrease in the on-fraction for most nanocrystals and, correspondingly, a substantial decrease in the photoluminescence intensity for a thin film annealed at this temperature. We attribute the differences in behavior among individual nanocrystals to heterogeneity in the distribution of trap states that are initially present. X-ray photoelectron, time-resolved photoluminescence, and transient absorption spectroscopies performed on thin films of CsPbBr<sub>3</sub>@SiO<sub>2</sub> nanocrystals indicate that thermal annealing heals electron traps by passivating surface Pb ions and simultaneously creates hole traps through the formation of Pb and Cs vacancies. The relative rates of these parallel processes depend on the annealing temperature, which are important to account for when developing passivation strategies for lead halide perovskite nanocrystals in optoelectronic devices that will operate at elevated temperatures.\\n</p><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>\",\"PeriodicalId\":713,\"journal\":{\"name\":\"Nano Research\",\"volume\":\"17 :\",\"pages\":\"10363 - 10375\"},\"PeriodicalIF\":9.0000,\"publicationDate\":\"2024-11-11\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Nano Research\",\"FirstCategoryId\":\"88\",\"ListUrlMain\":\"https://link.springer.com/article/10.1007/s12274-024-6989-3\",\"RegionNum\":2,\"RegionCategory\":\"材料科学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q1\",\"JCRName\":\"CHEMISTRY, PHYSICAL\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Nano Research","FirstCategoryId":"88","ListUrlMain":"https://link.springer.com/article/10.1007/s12274-024-6989-3","RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"CHEMISTRY, PHYSICAL","Score":null,"Total":0}
Single-particle photoluminescence connects thermal processing with heterogeneity in the trap distribution of cesium lead bromide nanocrystals
Understanding the mechanisms of degradation in lead halide perovskite nanocrystals is critical for their future application in optoelectronic devices. We report single-particle measurements of the photoluminescence from cesium lead bromide nanocrystals coated with a silica shell (CsPbBr3@SiO2). Through correlative imaging, we quantified changes in the fluorescence intensity trajectories of the same nanocrystals before and after annealing them at different temperatures. We observe that nearly equal numbers of CsPbBr3@SiO2 nanocrystals exhibit an increase versus decrease in the amount of time they spend in an emissive state after annealing at temperatures of 70 and 100 °C. On the other hand, annealing at 120 °C produces a decrease in the on-fraction for most nanocrystals and, correspondingly, a substantial decrease in the photoluminescence intensity for a thin film annealed at this temperature. We attribute the differences in behavior among individual nanocrystals to heterogeneity in the distribution of trap states that are initially present. X-ray photoelectron, time-resolved photoluminescence, and transient absorption spectroscopies performed on thin films of CsPbBr3@SiO2 nanocrystals indicate that thermal annealing heals electron traps by passivating surface Pb ions and simultaneously creates hole traps through the formation of Pb and Cs vacancies. The relative rates of these parallel processes depend on the annealing temperature, which are important to account for when developing passivation strategies for lead halide perovskite nanocrystals in optoelectronic devices that will operate at elevated temperatures.
期刊介绍:
Nano Research is a peer-reviewed, international and interdisciplinary research journal that focuses on all aspects of nanoscience and nanotechnology. It solicits submissions in various topical areas, from basic aspects of nanoscale materials to practical applications. The journal publishes articles on synthesis, characterization, and manipulation of nanomaterials; nanoscale physics, electrical transport, and quantum physics; scanning probe microscopy and spectroscopy; nanofluidics; nanosensors; nanoelectronics and molecular electronics; nano-optics, nano-optoelectronics, and nano-photonics; nanomagnetics; nanobiotechnology and nanomedicine; and nanoscale modeling and simulations. Nano Research offers readers a combination of authoritative and comprehensive Reviews, original cutting-edge research in Communication and Full Paper formats. The journal also prioritizes rapid review to ensure prompt publication.