Kylie M. Lytle, Emma L. Brass, Benjamin J. Roman and Matthew T. Sheldon*,
{"title":"CsPbBr3 包晶石纳米晶体中反斯托克斯光致发光的热激活:表面极龙态的作用。","authors":"Kylie M. Lytle, Emma L. Brass, Benjamin J. Roman and Matthew T. Sheldon*, ","doi":"10.1021/acsnano.4c03548","DOIUrl":null,"url":null,"abstract":"<p >Optically driven cooling of a material, or optical refrigeration, is possible when optical up-conversion via anti-Stokes photoluminescence (ASPL) is achieved with near-unity quantum yield. The recent demonstration of optical cooling of CsPbBr<sub>3</sub> perovskite nanocrystals (NCs) has provided a path forward in the development of semiconductor-based optical refrigeration strategies. However, the mechanism of ASPL in CsPbBr<sub>3</sub> NCs is not yet settled, and the prospects for cooling technologies strongly depend on details of the mechanism. By analyzing the Arrhenius behavior of ASPL in CsPbBr<sub>3</sub> NCs, we investigated the relationship between the average energy gained per photon during up conversion, Δ<i>E</i>, and the thermal activation energy, <i>E</i><sub>a</sub>. We find that <i>E</i><sub>a</sub> is systematically larger than Δ<i>E</i>, and that <i>E</i><sub>a</sub> increases for larger Δ<i>E</i>. We suggest that the additional energetic cost is due to a rearrangement of the crystal lattice as charge carriers pass from surface localized, structurally distinct sub-gap polaron states to the free exciton state during up-conversion. Our interpretation is further corroborated by quantifying the impact of ligand coverage on the NC surface. These findings help inform the development of CsPbBr<sub>3</sub> NCs for applications in optical refrigeration.</p>","PeriodicalId":21,"journal":{"name":"ACS Nano","volume":null,"pages":null},"PeriodicalIF":15.8000,"publicationDate":"2024-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Thermal Activation of Anti-Stokes Photoluminescence in CsPbBr3 Perovskite Nanocrystals: The Role of Surface Polaron States\",\"authors\":\"Kylie M. Lytle, Emma L. Brass, Benjamin J. Roman and Matthew T. Sheldon*, \",\"doi\":\"10.1021/acsnano.4c03548\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p >Optically driven cooling of a material, or optical refrigeration, is possible when optical up-conversion via anti-Stokes photoluminescence (ASPL) is achieved with near-unity quantum yield. The recent demonstration of optical cooling of CsPbBr<sub>3</sub> perovskite nanocrystals (NCs) has provided a path forward in the development of semiconductor-based optical refrigeration strategies. However, the mechanism of ASPL in CsPbBr<sub>3</sub> NCs is not yet settled, and the prospects for cooling technologies strongly depend on details of the mechanism. By analyzing the Arrhenius behavior of ASPL in CsPbBr<sub>3</sub> NCs, we investigated the relationship between the average energy gained per photon during up conversion, Δ<i>E</i>, and the thermal activation energy, <i>E</i><sub>a</sub>. We find that <i>E</i><sub>a</sub> is systematically larger than Δ<i>E</i>, and that <i>E</i><sub>a</sub> increases for larger Δ<i>E</i>. We suggest that the additional energetic cost is due to a rearrangement of the crystal lattice as charge carriers pass from surface localized, structurally distinct sub-gap polaron states to the free exciton state during up-conversion. Our interpretation is further corroborated by quantifying the impact of ligand coverage on the NC surface. These findings help inform the development of CsPbBr<sub>3</sub> NCs for applications in optical refrigeration.</p>\",\"PeriodicalId\":21,\"journal\":{\"name\":\"ACS Nano\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":15.8000,\"publicationDate\":\"2024-07-05\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"ACS Nano\",\"FirstCategoryId\":\"88\",\"ListUrlMain\":\"https://pubs.acs.org/doi/10.1021/acsnano.4c03548\",\"RegionNum\":1,\"RegionCategory\":\"材料科学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q1\",\"JCRName\":\"CHEMISTRY, MULTIDISCIPLINARY\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"ACS Nano","FirstCategoryId":"88","ListUrlMain":"https://pubs.acs.org/doi/10.1021/acsnano.4c03548","RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"CHEMISTRY, MULTIDISCIPLINARY","Score":null,"Total":0}
Thermal Activation of Anti-Stokes Photoluminescence in CsPbBr3 Perovskite Nanocrystals: The Role of Surface Polaron States
Optically driven cooling of a material, or optical refrigeration, is possible when optical up-conversion via anti-Stokes photoluminescence (ASPL) is achieved with near-unity quantum yield. The recent demonstration of optical cooling of CsPbBr3 perovskite nanocrystals (NCs) has provided a path forward in the development of semiconductor-based optical refrigeration strategies. However, the mechanism of ASPL in CsPbBr3 NCs is not yet settled, and the prospects for cooling technologies strongly depend on details of the mechanism. By analyzing the Arrhenius behavior of ASPL in CsPbBr3 NCs, we investigated the relationship between the average energy gained per photon during up conversion, ΔE, and the thermal activation energy, Ea. We find that Ea is systematically larger than ΔE, and that Ea increases for larger ΔE. We suggest that the additional energetic cost is due to a rearrangement of the crystal lattice as charge carriers pass from surface localized, structurally distinct sub-gap polaron states to the free exciton state during up-conversion. Our interpretation is further corroborated by quantifying the impact of ligand coverage on the NC surface. These findings help inform the development of CsPbBr3 NCs for applications in optical refrigeration.
期刊介绍:
ACS Nano, published monthly, serves as an international forum for comprehensive articles on nanoscience and nanotechnology research at the intersections of chemistry, biology, materials science, physics, and engineering. The journal fosters communication among scientists in these communities, facilitating collaboration, new research opportunities, and advancements through discoveries. ACS Nano covers synthesis, assembly, characterization, theory, and simulation of nanostructures, nanobiotechnology, nanofabrication, methods and tools for nanoscience and nanotechnology, and self- and directed-assembly. Alongside original research articles, it offers thorough reviews, perspectives on cutting-edge research, and discussions envisioning the future of nanoscience and nanotechnology.