{"title":"火花等离子烧结氧空位诱导Al2O3-TiO2陶瓷的带隙调谐","authors":"Mahdi Hajihashemi, Morteza Shamanian, Fakhreddin Ashrafizadeh","doi":"10.1007/s10832-021-00273-4","DOIUrl":null,"url":null,"abstract":"<div><p>Optical and photocatalytic applications of Al<sub>2</sub>O<sub>3</sub> and TiO<sub>2</sub> ceramics are limited, especially under visible light, due to their wide bandgap; so, this parameter plays an important and even decisive role in these applications. In the present study, Al<sub>2</sub>O<sub>3</sub>-TiO<sub>2</sub> ball milled powders were sintered by spark plasma sintering (SPS) at 1573 K. The products were characterized using XRD, SEM, UV–Vis and electrochemical methods. The results indicated effective improvement in the light absorbing capability of the composites (up to 95%) under visible light and the decrease of the band gap down to 2.2 eV owing to the increase of oxygen vacancies, which was, in turn, due to the reduced atmosphere of the sintering process. In addition, formation of a new phase (Al<sub>2</sub>TiO<sub>5</sub>) during sintering greatly affected the absorption of Al<sub>2</sub>O<sub>3</sub>-TiO<sub>2</sub> composites in the visible light region due to the increase in the fraction of the charge carrier separation centers. Photo-luminescence spectroscopy also showed that tialite formation could be effective in improving the charge separation efficiency.</p></div>","PeriodicalId":625,"journal":{"name":"Journal of Electroceramics","volume":"48 1","pages":"35 - 50"},"PeriodicalIF":1.7000,"publicationDate":"2021-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"1","resultStr":"{\"title\":\"Band gap tuning of oxygen vacancy-induced Al2O3-TiO2 ceramics processed by spark plasma sintering\",\"authors\":\"Mahdi Hajihashemi, Morteza Shamanian, Fakhreddin Ashrafizadeh\",\"doi\":\"10.1007/s10832-021-00273-4\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><p>Optical and photocatalytic applications of Al<sub>2</sub>O<sub>3</sub> and TiO<sub>2</sub> ceramics are limited, especially under visible light, due to their wide bandgap; so, this parameter plays an important and even decisive role in these applications. In the present study, Al<sub>2</sub>O<sub>3</sub>-TiO<sub>2</sub> ball milled powders were sintered by spark plasma sintering (SPS) at 1573 K. The products were characterized using XRD, SEM, UV–Vis and electrochemical methods. The results indicated effective improvement in the light absorbing capability of the composites (up to 95%) under visible light and the decrease of the band gap down to 2.2 eV owing to the increase of oxygen vacancies, which was, in turn, due to the reduced atmosphere of the sintering process. In addition, formation of a new phase (Al<sub>2</sub>TiO<sub>5</sub>) during sintering greatly affected the absorption of Al<sub>2</sub>O<sub>3</sub>-TiO<sub>2</sub> composites in the visible light region due to the increase in the fraction of the charge carrier separation centers. Photo-luminescence spectroscopy also showed that tialite formation could be effective in improving the charge separation efficiency.</p></div>\",\"PeriodicalId\":625,\"journal\":{\"name\":\"Journal of Electroceramics\",\"volume\":\"48 1\",\"pages\":\"35 - 50\"},\"PeriodicalIF\":1.7000,\"publicationDate\":\"2021-11-11\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"1\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Journal of Electroceramics\",\"FirstCategoryId\":\"88\",\"ListUrlMain\":\"https://link.springer.com/article/10.1007/s10832-021-00273-4\",\"RegionNum\":4,\"RegionCategory\":\"材料科学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q2\",\"JCRName\":\"MATERIALS SCIENCE, CERAMICS\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Electroceramics","FirstCategoryId":"88","ListUrlMain":"https://link.springer.com/article/10.1007/s10832-021-00273-4","RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"MATERIALS SCIENCE, CERAMICS","Score":null,"Total":0}
Band gap tuning of oxygen vacancy-induced Al2O3-TiO2 ceramics processed by spark plasma sintering
Optical and photocatalytic applications of Al2O3 and TiO2 ceramics are limited, especially under visible light, due to their wide bandgap; so, this parameter plays an important and even decisive role in these applications. In the present study, Al2O3-TiO2 ball milled powders were sintered by spark plasma sintering (SPS) at 1573 K. The products were characterized using XRD, SEM, UV–Vis and electrochemical methods. The results indicated effective improvement in the light absorbing capability of the composites (up to 95%) under visible light and the decrease of the band gap down to 2.2 eV owing to the increase of oxygen vacancies, which was, in turn, due to the reduced atmosphere of the sintering process. In addition, formation of a new phase (Al2TiO5) during sintering greatly affected the absorption of Al2O3-TiO2 composites in the visible light region due to the increase in the fraction of the charge carrier separation centers. Photo-luminescence spectroscopy also showed that tialite formation could be effective in improving the charge separation efficiency.
期刊介绍:
While ceramics have traditionally been admired for their mechanical, chemical and thermal stability, their unique electrical, optical and magnetic properties have become of increasing importance in many key technologies including communications, energy conversion and storage, electronics and automation. Electroceramics benefit greatly from their versatility in properties including:
-insulating to metallic and fast ion conductivity
-piezo-, ferro-, and pyro-electricity
-electro- and nonlinear optical properties
-feromagnetism.
When combined with thermal, mechanical, and chemical stability, these properties often render them the materials of choice.
The Journal of Electroceramics is dedicated to providing a forum of discussion cutting across issues in electrical, optical, and magnetic ceramics. Driven by the need for miniaturization, cost, and enhanced functionality, the field of electroceramics is growing rapidly in many new directions. The Journal encourages discussions of resultant trends concerning silicon-electroceramic integration, nanotechnology, ceramic-polymer composites, grain boundary and defect engineering, etc.