An investigation into the surface phase of nanostructured zirconia by conventional UV spectroscopy
作者:
Zhao, Yubao;Fu, Shifu;Li, Hui;Tian, Xiaoning;Nie, Changming
期刊:
Materials Letters ,2008年62(15):2207-2210 ISSN:0167-577X
通讯作者:
Zhao, YB
作者机构:
[Zhao, Yubao; Fu, Shifu; Li, Hui; Tian, Xiaoning; Nie, Changming] Nanhua Univ, Coll Chem & Chem Engn, Hengyang 421001, Peoples R China.
通讯机构:
[Zhao, YB ] ;Nanhua Univ, Coll Chem & Chem Engn, Hengyang 421001, Peoples R China.
关键词:
zirconia;phase transformation;UV spectroscopy;X-ray diffraction
摘要:
The phase features of nanostructured zirconia samples were characterized by conventional UV spectroscopy and XRD. While XRD identification shows the phase in the bulk of zirconia prepared by refluxing a ZrOCl<inf>2</inf> solution and calcining at 673 K is pure monoclinic, a good few tetragonal ZrO<inf>2</inf> in its surface regions was detected by surface-sensitive UV spectroscopy. Although about 50% of the zirconia from 353 K aging and calcining at 673 K exists as monoclinic in bulk, the surface structure is pure tetragonal. Results show that the thermodynamically feasible tetragonal phase always stays on the surface and the phase transition from tetragonal to monoclinic takes place initially at the core. ©2007 Elsevier B.V. All rights reserved.
语种:
英文
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氮铈共掺杂纳米TiO2的制备和光催化活性研究
作者:
周亮;邓健;廖力夫;赵玉宝;肖方竹;...
期刊:
应用化工 ,2008年37(8):857-860+878 ISSN:1671-3206
作者机构:
南华大学,公共卫生学院,湖南,衡阳,421001;南华大学,化学化工学院,湖南,衡阳,421001;[周亮; 安林; 肖方竹; 邓健; 赵玉宝; 廖力夫] 南华大学
关键词:
甲基橙;氮铈共掺杂;水解沉淀;光催化
摘要:
采用水解沉淀法分别制备了未掺杂、氮掺杂和不同Ce4+浓度的氮、铈共掺杂纳米二氧化钛粉体,并利用XRD、TEM、XPS、UV-vis对其进行表征,以甲基橙的光催化降解为模型反应,考察其在太阳光下的光催化活性.结果表明,450 ℃下煅烧3 h制备的纳米TiO2粉体均为锐态矿型,铈的掺入使衍射峰宽化;氮、铈共掺杂能抑制锐钛矿晶粒的生长,减少团聚,使晶粒细化.N取代了TiO2晶格中的部分氧原子形成N2p掺杂能级,而铈以Ce4+、Ce3+两种价态存在于TiO2中.氮、铈的协同作用不仅使TiO2的光吸收带边红移,也能明显提高TiO2在紫外光区的吸收强度.光催化降解甲基橙实验结果表明:当Ce4+掺杂量为0.6%时,Ce-N-TiO2的光催化效率最高,约为纯二氧化钛的2倍.
语种:
中文
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Phase transformation of zirconia in sulfated zirconia–LiCl system
作者:
Zhao, Yubao* ;Yuan, Xiaohong;Liu, Chuanxiang;Huang, Chuanjing;Wan, Huilin
期刊:
Materials Letters ,2007年61(4-5):942-943 ISSN:0167-577X
通讯作者:
Zhao, Yubao
作者机构:
[Zhao, Yubao] Xiamen Univ, Dept Chem, State Key Lab Phys Chem Solid Surface, Xiamen 361005, Peoples R China.;Xiamen Univ, Inst Phys Chem, Xiamen 361005, Peoples R China.;Nanhua Univ, Coll Chem & Chem Engn, Hengyang 421001, Hunan, Peoples R China.
通讯机构:
[Zhao, Yubao] X;Xiamen Univ, Dept Chem, State Key Lab Phys Chem Solid Surface, Xiamen 361005, Peoples R China.
关键词:
Zirconia;Phase transformation;Raman spectroscopy;X-ray diffraction
摘要:
The phase transformation from tetragonal to monoclinic of zirconia for a series of sulfated zirconia–LiCl samples was characterized by ultraviolet Raman spectroscopy (UVRS) and X-ray diffraction (XRD). Results show that such phase transformation increases with increasing LiCl content and the monoclinic phase is first detected by XRD than that by UVRS for the sample with Li content of 0.5 wt.%. The comparison between XRD and UVRS characterizations indicates that the phase transition takes place initially at the core.
语种:
英文
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物理化学教学改革的初探
作者:
贾晓辉;赵玉宝;丁娟
期刊:
产业与科技论坛 ,2007年(6):103-104 ISSN:1673-5641
作者机构:
南华大学化学化工学院
关键词:
物理化学;教学改革;教学方法
摘要:
分析高校物理化学教学中存在的问题,提出深化物理化学教学改革、增强人才能力培养的思路与方法,并在教学中收到了良好的效果。
语种:
中文
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超强碱负载LiCl催化剂上乙烷氧化脱氢制乙烯
作者:
赵玉宝;袁晓红;傅仕福;万惠霖
作者机构:
[赵玉宝; 袁晓红; 傅仕福; 万惠霖] 南华大学化学化工学院;[赵玉宝; 袁晓红; 傅仕福; 万惠霖] 厦门大学化学化工学院国家重点实验室
会议名称:
第十三届全国催化学术会议
会议时间:
2006-09
会议地点:
中国甘肃兰州
关键词:
超强碱;氯化锂;乙烷;氧化脱氢;乙烯
摘要:
<正>众多乙烷氧化脱氢(ODE)催化剂体系中,Lunsford等开发的Li-MgO(-Cl)和Wang等研究的 LiCl/SO42--ZrO2体系,因其能在高乙烷转化率下保持高的乙烯选择性受到了人们的广泛关注。研究表明,相对于以固体酸SO42--ZrO2为载体的负载型LiCl催化剂而言,以碱性MgO为载体的负载型
语种:
中文
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