Carlos Alberto López, Carmen Abia, Javier Gainza, João Elias Rodrigues, Brenda Martinelli, Federico Serrano-Sánchez, Romualdo Santos Silva Jr., Mateus M. Ferrer, Oscar J. Dura, José Luis Martínez, María Teresa Fernández-Díaz and José Antonio Alonso*,
{"title":"揭示通过机械化学方法获得的二维 CsSn2Br5 卤化物的结构特性、光学行为和热电性能。","authors":"Carlos Alberto López, Carmen Abia, Javier Gainza, João Elias Rodrigues, Brenda Martinelli, Federico Serrano-Sánchez, Romualdo Santos Silva Jr., Mateus M. Ferrer, Oscar J. Dura, José Luis Martínez, María Teresa Fernández-Díaz and José Antonio Alonso*, ","doi":"10.1021/acs.inorgchem.4c01861","DOIUrl":null,"url":null,"abstract":"<p >Metal halide perovskites with a two-dimensional structure are utilized in photovoltaics and optoelectronics. High-crystallinity CsSn<sub>2</sub>Br<sub>5</sub> specimens have been synthesized via ball milling. Differential scanning calorimetry curves show melting at 553 K (endothermic) and recrystallization at 516 K (exothermic). Structural analysis using synchrotron X-ray diffraction data, collected from 100 to 373 K, allows for the determination of Debye model parameters. This analysis provides insights into the relative Cs–Br and Sn–Br chemical bonds within the tetragonal structure (space group: <i>I</i>4/<i>mcm</i>), which remains stable throughout the temperature range studied. Combined with neutron data, X–N techniques permit the identification of the Sn<sup>2+</sup> lone electron pair (5s<sup>2</sup>) in the two-dimensional framework, occupying empty space opposite to the four Sn–Br bonds of the pyramidal [SnBr<sub>4</sub>] coordination polyhedra. Additionally, diffuse reflectance UV–vis spectroscopy unveils an indirect optical gap of approximately ∼3.3 eV, aligning with the calculated value from the <i>B3LYP</i>-DFT method (∼3.2 eV). The material exhibits a positive Seebeck coefficient as high as 6.5 × 10<sup>4</sup> μV K<sup>–1</sup> at 350 K, which evolves down to negative values of −3.0 × 10<sup>3</sup> μV K<sup>–1</sup> at 550 K, surpassing values reported for other halide perovskites. Notably, the thermal conductivity remains exceptionally low, between 0.32 and 0.25 W m<sup>–1</sup> K<sup>–1</sup>.</p><p >2D CsSn<sub>2</sub>Br<sub>5</sub>, prepared by mechanochemistry, is studied from SXRD and NPD data in the 100−373 K interval. The Sn<sup>2+</sup> lone electron pair is identified by X–N techniques. UV−vis spectroscopy unveils an optical gap of ∼3.3 eV, matching the calculated value from the <i>B3LYP</i>-DFT method (∼3.2 eV). The material demonstrates a remarkable thermoelectric performance comparable to those of other tin and lead halides, including a significant positive Seebeck coefficient and low thermal conductivity.</p>","PeriodicalId":40,"journal":{"name":"Inorganic Chemistry","volume":null,"pages":null},"PeriodicalIF":4.3000,"publicationDate":"2024-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/epdf/10.1021/acs.inorgchem.4c01861","citationCount":"0","resultStr":"{\"title\":\"Unveiling the Structural Properties, Optical Behavior, and Thermoelectric Performance of 2D CsSn2Br5 Halide Obtained by Mechanochemistry\",\"authors\":\"Carlos Alberto López, Carmen Abia, Javier Gainza, João Elias Rodrigues, Brenda Martinelli, Federico Serrano-Sánchez, Romualdo Santos Silva Jr., Mateus M. Ferrer, Oscar J. Dura, José Luis Martínez, María Teresa Fernández-Díaz and José Antonio Alonso*, \",\"doi\":\"10.1021/acs.inorgchem.4c01861\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p >Metal halide perovskites with a two-dimensional structure are utilized in photovoltaics and optoelectronics. High-crystallinity CsSn<sub>2</sub>Br<sub>5</sub> specimens have been synthesized via ball milling. Differential scanning calorimetry curves show melting at 553 K (endothermic) and recrystallization at 516 K (exothermic). Structural analysis using synchrotron X-ray diffraction data, collected from 100 to 373 K, allows for the determination of Debye model parameters. This analysis provides insights into the relative Cs–Br and Sn–Br chemical bonds within the tetragonal structure (space group: <i>I</i>4/<i>mcm</i>), which remains stable throughout the temperature range studied. Combined with neutron data, X–N techniques permit the identification of the Sn<sup>2+</sup> lone electron pair (5s<sup>2</sup>) in the two-dimensional framework, occupying empty space opposite to the four Sn–Br bonds of the pyramidal [SnBr<sub>4</sub>] coordination polyhedra. Additionally, diffuse reflectance UV–vis spectroscopy unveils an indirect optical gap of approximately ∼3.3 eV, aligning with the calculated value from the <i>B3LYP</i>-DFT method (∼3.2 eV). The material exhibits a positive Seebeck coefficient as high as 6.5 × 10<sup>4</sup> μV K<sup>–1</sup> at 350 K, which evolves down to negative values of −3.0 × 10<sup>3</sup> μV K<sup>–1</sup> at 550 K, surpassing values reported for other halide perovskites. Notably, the thermal conductivity remains exceptionally low, between 0.32 and 0.25 W m<sup>–1</sup> K<sup>–1</sup>.</p><p >2D CsSn<sub>2</sub>Br<sub>5</sub>, prepared by mechanochemistry, is studied from SXRD and NPD data in the 100−373 K interval. The Sn<sup>2+</sup> lone electron pair is identified by X–N techniques. UV−vis spectroscopy unveils an optical gap of ∼3.3 eV, matching the calculated value from the <i>B3LYP</i>-DFT method (∼3.2 eV). The material demonstrates a remarkable thermoelectric performance comparable to those of other tin and lead halides, including a significant positive Seebeck coefficient and low thermal conductivity.</p>\",\"PeriodicalId\":40,\"journal\":{\"name\":\"Inorganic Chemistry\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":4.3000,\"publicationDate\":\"2024-06-26\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"https://pubs.acs.org/doi/epdf/10.1021/acs.inorgchem.4c01861\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Inorganic Chemistry\",\"FirstCategoryId\":\"92\",\"ListUrlMain\":\"https://pubs.acs.org/doi/10.1021/acs.inorgchem.4c01861\",\"RegionNum\":2,\"RegionCategory\":\"化学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q1\",\"JCRName\":\"CHEMISTRY, INORGANIC & NUCLEAR\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Inorganic Chemistry","FirstCategoryId":"92","ListUrlMain":"https://pubs.acs.org/doi/10.1021/acs.inorgchem.4c01861","RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"CHEMISTRY, INORGANIC & NUCLEAR","Score":null,"Total":0}
Unveiling the Structural Properties, Optical Behavior, and Thermoelectric Performance of 2D CsSn2Br5 Halide Obtained by Mechanochemistry
Metal halide perovskites with a two-dimensional structure are utilized in photovoltaics and optoelectronics. High-crystallinity CsSn2Br5 specimens have been synthesized via ball milling. Differential scanning calorimetry curves show melting at 553 K (endothermic) and recrystallization at 516 K (exothermic). Structural analysis using synchrotron X-ray diffraction data, collected from 100 to 373 K, allows for the determination of Debye model parameters. This analysis provides insights into the relative Cs–Br and Sn–Br chemical bonds within the tetragonal structure (space group: I4/mcm), which remains stable throughout the temperature range studied. Combined with neutron data, X–N techniques permit the identification of the Sn2+ lone electron pair (5s2) in the two-dimensional framework, occupying empty space opposite to the four Sn–Br bonds of the pyramidal [SnBr4] coordination polyhedra. Additionally, diffuse reflectance UV–vis spectroscopy unveils an indirect optical gap of approximately ∼3.3 eV, aligning with the calculated value from the B3LYP-DFT method (∼3.2 eV). The material exhibits a positive Seebeck coefficient as high as 6.5 × 104 μV K–1 at 350 K, which evolves down to negative values of −3.0 × 103 μV K–1 at 550 K, surpassing values reported for other halide perovskites. Notably, the thermal conductivity remains exceptionally low, between 0.32 and 0.25 W m–1 K–1.
2D CsSn2Br5, prepared by mechanochemistry, is studied from SXRD and NPD data in the 100−373 K interval. The Sn2+ lone electron pair is identified by X–N techniques. UV−vis spectroscopy unveils an optical gap of ∼3.3 eV, matching the calculated value from the B3LYP-DFT method (∼3.2 eV). The material demonstrates a remarkable thermoelectric performance comparable to those of other tin and lead halides, including a significant positive Seebeck coefficient and low thermal conductivity.
期刊介绍:
Inorganic Chemistry publishes fundamental studies in all phases of inorganic chemistry. Coverage includes experimental and theoretical reports on quantitative studies of structure and thermodynamics, kinetics, mechanisms of inorganic reactions, bioinorganic chemistry, and relevant aspects of organometallic chemistry, solid-state phenomena, and chemical bonding theory. Emphasis is placed on the synthesis, structure, thermodynamics, reactivity, spectroscopy, and bonding properties of significant new and known compounds.