Investigation of the Structural and Luminescent Properties and the Chromium Ion Valence of Li<sub>2</sub>CaGeO<sub>4</sub> Crystals Doped with Cr<sup>4+</sup> Ions
Herein, we report on the growth of Cr<sup>4+</sup>–Li<sub>2</sub>CaGeO<sub>4</sub> crystals by the flux growth method from the flux of LiCl, as well as on the effect of doping Li<sub>2</sub>CaGeO<sub>4</sub> with Cr<sup>4+</sup>...
| Main Authors: | , , , , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2020-11-01
|
| Series: | Crystals |
| Subjects: | |
| Online Access: | https://www.mdpi.com/2073-4352/10/11/1019 |
| _version_ | 1827702650876985344 |
|---|---|
| author | Dongmei Wang Xiaowei Zhang Xinyu Wang Zhuang Leng Qianqian Yang Wen Ji Hai Lin Fanming Zeng Chun Li Zhongmin Su |
| author_facet | Dongmei Wang Xiaowei Zhang Xinyu Wang Zhuang Leng Qianqian Yang Wen Ji Hai Lin Fanming Zeng Chun Li Zhongmin Su |
| author_sort | Dongmei Wang |
| collection | DOAJ |
| description | Herein, we report on the growth of Cr<sup>4+</sup>–Li<sub>2</sub>CaGeO<sub>4</sub> crystals by the flux growth method from the flux of LiCl, as well as on the effect of doping Li<sub>2</sub>CaGeO<sub>4</sub> with Cr<sup>4+</sup> ions on the NIR region spectral properties and crystal structure. The results quantified the occupancy of Cr<sup>4+</sup> in Ge<sup>4+</sup> sites. The emission spectrum presented broad bands in the NIR region, i.e., 1000–1500 nm excited by 980 nm, with maximum peaks at 1200 nm at room temperature caused by the transition of <sup>3</sup>T<sub>2</sub>→<sup>3</sup>A<sub>2</sub> in Cr<sup>4+</sup> ions. The lifetime decreased with the Cr<sup>4+</sup> ion doping concentration, specifically from 14.038 to 12.224 ms. The chemical composition and the valence state of chromium in Li<sub>2</sub>CaGeO<sub>4</sub> were analyzed using X-ray photoelectron spectroscopy, which showed that the chromium in Li<sub>2</sub>CaGeO<sub>4</sub> was tetravalent and no trivalent chromium was found. Therefore, the Cr<sup>4+</sup>–Li<sub>2</sub>CaGeO<sub>4</sub> crystal has a great potential and future in optical applications. |
| first_indexed | 2024-03-10T15:00:16Z |
| format | Article |
| id | doaj.art-df38501a6d2142338baef51edafd5f3d |
| institution | Directory Open Access Journal |
| issn | 2073-4352 |
| language | English |
| last_indexed | 2024-03-10T15:00:16Z |
| publishDate | 2020-11-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Crystals |
| spelling | doaj.art-df38501a6d2142338baef51edafd5f3d2023-11-20T20:16:50ZengMDPI AGCrystals2073-43522020-11-011011101910.3390/cryst10111019Investigation of the Structural and Luminescent Properties and the Chromium Ion Valence of Li<sub>2</sub>CaGeO<sub>4</sub> Crystals Doped with Cr<sup>4+</sup> IonsDongmei Wang0Xiaowei Zhang1Xinyu Wang2Zhuang Leng3Qianqian Yang4Wen Ji5Hai Lin6Fanming Zeng7Chun Li8Zhongmin Su9School of Materials Science and Engineering, Changchun University of Science and Technology, Changchun 130022, ChinaSchool of Materials Science and Engineering, Changchun University of Science and Technology, Changchun 130022, ChinaSchool of Materials Science and Engineering, Changchun University of Science and Technology, Changchun 130022, ChinaSchool of Materials Science and Engineering, Changchun University of Science and Technology, Changchun 130022, ChinaSchool of Materials Science and Engineering, Changchun University of Science and Technology, Changchun 130022, ChinaSchool of Materials Science and Engineering, Changchun University of Science and Technology, Changchun 130022, ChinaSchool of Materials Science and Engineering, Changchun University of Science and Technology, Changchun 130022, ChinaSchool of Materials Science and Engineering, Changchun University of Science and Technology, Changchun 130022, ChinaSchool of Materials Science and Engineering, Changchun University of Science and Technology, Changchun 130022, ChinaSchool of Materials Science and Engineering, Changchun University of Science and Technology, Changchun 130022, ChinaHerein, we report on the growth of Cr<sup>4+</sup>–Li<sub>2</sub>CaGeO<sub>4</sub> crystals by the flux growth method from the flux of LiCl, as well as on the effect of doping Li<sub>2</sub>CaGeO<sub>4</sub> with Cr<sup>4+</sup> ions on the NIR region spectral properties and crystal structure. The results quantified the occupancy of Cr<sup>4+</sup> in Ge<sup>4+</sup> sites. The emission spectrum presented broad bands in the NIR region, i.e., 1000–1500 nm excited by 980 nm, with maximum peaks at 1200 nm at room temperature caused by the transition of <sup>3</sup>T<sub>2</sub>→<sup>3</sup>A<sub>2</sub> in Cr<sup>4+</sup> ions. The lifetime decreased with the Cr<sup>4+</sup> ion doping concentration, specifically from 14.038 to 12.224 ms. The chemical composition and the valence state of chromium in Li<sub>2</sub>CaGeO<sub>4</sub> were analyzed using X-ray photoelectron spectroscopy, which showed that the chromium in Li<sub>2</sub>CaGeO<sub>4</sub> was tetravalent and no trivalent chromium was found. Therefore, the Cr<sup>4+</sup>–Li<sub>2</sub>CaGeO<sub>4</sub> crystal has a great potential and future in optical applications.https://www.mdpi.com/2073-4352/10/11/1019Cr<sup>4+</sup>–Li<sub>2</sub>CaGeO<sub>4</sub>crystal growthNIR luminescence propertyXPS |
| spellingShingle | Dongmei Wang Xiaowei Zhang Xinyu Wang Zhuang Leng Qianqian Yang Wen Ji Hai Lin Fanming Zeng Chun Li Zhongmin Su Investigation of the Structural and Luminescent Properties and the Chromium Ion Valence of Li<sub>2</sub>CaGeO<sub>4</sub> Crystals Doped with Cr<sup>4+</sup> Ions Crystals Cr<sup>4+</sup>–Li<sub>2</sub>CaGeO<sub>4</sub> crystal growth NIR luminescence property XPS |
| title | Investigation of the Structural and Luminescent Properties and the Chromium Ion Valence of Li<sub>2</sub>CaGeO<sub>4</sub> Crystals Doped with Cr<sup>4+</sup> Ions |
| title_full | Investigation of the Structural and Luminescent Properties and the Chromium Ion Valence of Li<sub>2</sub>CaGeO<sub>4</sub> Crystals Doped with Cr<sup>4+</sup> Ions |
| title_fullStr | Investigation of the Structural and Luminescent Properties and the Chromium Ion Valence of Li<sub>2</sub>CaGeO<sub>4</sub> Crystals Doped with Cr<sup>4+</sup> Ions |
| title_full_unstemmed | Investigation of the Structural and Luminescent Properties and the Chromium Ion Valence of Li<sub>2</sub>CaGeO<sub>4</sub> Crystals Doped with Cr<sup>4+</sup> Ions |
| title_short | Investigation of the Structural and Luminescent Properties and the Chromium Ion Valence of Li<sub>2</sub>CaGeO<sub>4</sub> Crystals Doped with Cr<sup>4+</sup> Ions |
| title_sort | investigation of the structural and luminescent properties and the chromium ion valence of li sub 2 sub cageo sub 4 sub crystals doped with cr sup 4 sup ions |
| topic | Cr<sup>4+</sup>–Li<sub>2</sub>CaGeO<sub>4</sub> crystal growth NIR luminescence property XPS |
| url | https://www.mdpi.com/2073-4352/10/11/1019 |
| work_keys_str_mv | AT dongmeiwang investigationofthestructuralandluminescentpropertiesandthechromiumionvalenceoflisub2subcageosub4subcrystalsdopedwithcrsup4supions AT xiaoweizhang investigationofthestructuralandluminescentpropertiesandthechromiumionvalenceoflisub2subcageosub4subcrystalsdopedwithcrsup4supions AT xinyuwang investigationofthestructuralandluminescentpropertiesandthechromiumionvalenceoflisub2subcageosub4subcrystalsdopedwithcrsup4supions AT zhuangleng investigationofthestructuralandluminescentpropertiesandthechromiumionvalenceoflisub2subcageosub4subcrystalsdopedwithcrsup4supions AT qianqianyang investigationofthestructuralandluminescentpropertiesandthechromiumionvalenceoflisub2subcageosub4subcrystalsdopedwithcrsup4supions AT wenji investigationofthestructuralandluminescentpropertiesandthechromiumionvalenceoflisub2subcageosub4subcrystalsdopedwithcrsup4supions AT hailin investigationofthestructuralandluminescentpropertiesandthechromiumionvalenceoflisub2subcageosub4subcrystalsdopedwithcrsup4supions AT fanmingzeng investigationofthestructuralandluminescentpropertiesandthechromiumionvalenceoflisub2subcageosub4subcrystalsdopedwithcrsup4supions AT chunli investigationofthestructuralandluminescentpropertiesandthechromiumionvalenceoflisub2subcageosub4subcrystalsdopedwithcrsup4supions AT zhongminsu investigationofthestructuralandluminescentpropertiesandthechromiumionvalenceoflisub2subcageosub4subcrystalsdopedwithcrsup4supions |