Kai Chang , Jingyuan Liao , Zhaodong Zhang , Lingwei Zeng , Hong He , Guannan Li , Chunmei Li , Hua Lin , Jing Liu , Jianfeng Tang
{"title":"通过具有分离的[GeO6]八面体的Mn⁴+:K2Ge4O9晶体的控制结晶,增强了锗酸盐玻璃陶瓷中的红色发射","authors":"Kai Chang , Jingyuan Liao , Zhaodong Zhang , Lingwei Zeng , Hong He , Guannan Li , Chunmei Li , Hua Lin , Jing Liu , Jianfeng Tang","doi":"10.1016/j.jeurceramsoc.2025.117778","DOIUrl":null,"url":null,"abstract":"<div><div>Mn<sup>4+</sup>-activated luminescent materials are highly valued for their intense red emission. This study explores Mn<sup>4+</sup>-activated germanate glass-ceramics (GCs) made by in situ crystallization of a germanate parent glass. Controlled heat treatment enabled the sequential precipitation of two crystalline phases: Mn<sup>4+</sup>:K<sub>4</sub>Ge<sub>9</sub>O<sub>20</sub> (K4) and Mn<sup>4+</sup>:K<sub>2</sub>Ge<sub>4</sub>O<sub>9</sub> (K2). Mn<sup>4+</sup> ions favor six-fold coordinated Ge<sup>4+</sup> sites in these phases. The isolated trigonal-distorted [GeO<sub>6</sub>] octahedra in K2 enhance the <sup>2</sup>E → <sup>4</sup>A<sub>2</sub> emission intensity ten-fold compared to K4. Theoretical calculations indicate that Mn<sup>4+</sup> ions incorporation strengthens metal-ligand interaction and introduce new d-electron-related defect states within the forbidden band. The Mn<sup>4+</sup>:K2-embedded GC sample with 0.1 mol% Mn<sup>4+</sup> nominal concentration achieves optimal luminescence performance. It exhibits superior thermal stability compared to the Mn<sup>4+</sup>:K2 phosphor synthesized by solid-state reaction. These findings demonstrate the potential of Mn<sup>4+</sup>:K2-embedded germanate GC as an excellent red-emitting component for white LEDs, which can enhance indoor lighting quality by improving color rendering performance.</div></div>","PeriodicalId":17408,"journal":{"name":"Journal of The European Ceramic Society","volume":"46 2","pages":"Article 117778"},"PeriodicalIF":6.2000,"publicationDate":"2025-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Enhanced red emission in germanate glass-ceramics via controlled crystallization of Mn⁴⁺:K2Ge4O9 crystals with isolated [GeO6] octahedra\",\"authors\":\"Kai Chang , Jingyuan Liao , Zhaodong Zhang , Lingwei Zeng , Hong He , Guannan Li , Chunmei Li , Hua Lin , Jing Liu , Jianfeng Tang\",\"doi\":\"10.1016/j.jeurceramsoc.2025.117778\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><div>Mn<sup>4+</sup>-activated luminescent materials are highly valued for their intense red emission. This study explores Mn<sup>4+</sup>-activated germanate glass-ceramics (GCs) made by in situ crystallization of a germanate parent glass. Controlled heat treatment enabled the sequential precipitation of two crystalline phases: Mn<sup>4+</sup>:K<sub>4</sub>Ge<sub>9</sub>O<sub>20</sub> (K4) and Mn<sup>4+</sup>:K<sub>2</sub>Ge<sub>4</sub>O<sub>9</sub> (K2). Mn<sup>4+</sup> ions favor six-fold coordinated Ge<sup>4+</sup> sites in these phases. The isolated trigonal-distorted [GeO<sub>6</sub>] octahedra in K2 enhance the <sup>2</sup>E → <sup>4</sup>A<sub>2</sub> emission intensity ten-fold compared to K4. Theoretical calculations indicate that Mn<sup>4+</sup> ions incorporation strengthens metal-ligand interaction and introduce new d-electron-related defect states within the forbidden band. The Mn<sup>4+</sup>:K2-embedded GC sample with 0.1 mol% Mn<sup>4+</sup> nominal concentration achieves optimal luminescence performance. It exhibits superior thermal stability compared to the Mn<sup>4+</sup>:K2 phosphor synthesized by solid-state reaction. These findings demonstrate the potential of Mn<sup>4+</sup>:K2-embedded germanate GC as an excellent red-emitting component for white LEDs, which can enhance indoor lighting quality by improving color rendering performance.</div></div>\",\"PeriodicalId\":17408,\"journal\":{\"name\":\"Journal of The European Ceramic Society\",\"volume\":\"46 2\",\"pages\":\"Article 117778\"},\"PeriodicalIF\":6.2000,\"publicationDate\":\"2025-08-27\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Journal of The European Ceramic Society\",\"FirstCategoryId\":\"88\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S0955221925005990\",\"RegionNum\":2,\"RegionCategory\":\"材料科学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q1\",\"JCRName\":\"MATERIALS SCIENCE, CERAMICS\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of The European Ceramic Society","FirstCategoryId":"88","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0955221925005990","RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"MATERIALS SCIENCE, CERAMICS","Score":null,"Total":0}
Enhanced red emission in germanate glass-ceramics via controlled crystallization of Mn⁴⁺:K2Ge4O9 crystals with isolated [GeO6] octahedra
Mn4+-activated luminescent materials are highly valued for their intense red emission. This study explores Mn4+-activated germanate glass-ceramics (GCs) made by in situ crystallization of a germanate parent glass. Controlled heat treatment enabled the sequential precipitation of two crystalline phases: Mn4+:K4Ge9O20 (K4) and Mn4+:K2Ge4O9 (K2). Mn4+ ions favor six-fold coordinated Ge4+ sites in these phases. The isolated trigonal-distorted [GeO6] octahedra in K2 enhance the 2E → 4A2 emission intensity ten-fold compared to K4. Theoretical calculations indicate that Mn4+ ions incorporation strengthens metal-ligand interaction and introduce new d-electron-related defect states within the forbidden band. The Mn4+:K2-embedded GC sample with 0.1 mol% Mn4+ nominal concentration achieves optimal luminescence performance. It exhibits superior thermal stability compared to the Mn4+:K2 phosphor synthesized by solid-state reaction. These findings demonstrate the potential of Mn4+:K2-embedded germanate GC as an excellent red-emitting component for white LEDs, which can enhance indoor lighting quality by improving color rendering performance.
期刊介绍:
The Journal of the European Ceramic Society publishes the results of original research and reviews relating to ceramic materials. Papers of either an experimental or theoretical character will be welcomed on a fully international basis. The emphasis is on novel generic science concerning the relationships between processing, microstructure and properties of polycrystalline ceramics consolidated at high temperature. Papers may relate to any of the conventional categories of ceramic: structural, functional, traditional or composite. The central objective is to sustain a high standard of research quality by means of appropriate reviewing procedures.