氧化锡氧化铌共掺杂二氧化钛氧气响应特性的稳定性  

STABILITY OF OXYGEN RESPONSE CHARACTERISTICS ON STANNIC OXIDE AND NIOBIUM PENTOXIDE CODOPED TITANIA

作　　者：袁战恒[1] 张茂林[1] 郑程[1] 

机构地区：[1]西安交通大学电子系,西安710049

出　　处：《硅酸盐学报》2007年第9期1163-1168,共6页Journal of The Chinese Ceramic Society

摘　　要：研究了氧化锡(SnO2)、氧化铌(Nb2O3)共掺杂二氧化钛(TiO2)作为厚膜用氧传感器材料的响应特性。X射线衍射分析表明:适量掺杂使厚膜晶粒保持金红石结构,晶胞参数有所增大。扫描电子显微镜显示:厚膜在1280℃左右长时间(11h)保温,晶粒仍保持适度尺寸。X射线光电子能谱分析表明:较低的Nb掺杂浓度导致晶粒表面产生高浓度金属缺位(Vm),低温端(300℃)的氢气响应时间变短;高温端(600℃)的氧气响应时间急剧增大。Nb掺杂浓度较高时,低温端(300℃)氢气响应时间变长;高温端(600℃)氧气响应时间变短,但仍保持着响应特性的稳定性。结果表明:用摩尔分数x(Sn)=2.31%,x(Nb)=0.48%的组分,既能在同一结构下适度增加晶胞参数,又能相应提高掺杂浓度,可获得工作温度范围(300～600℃)内灵敏度和响应速度长期稳定的厚膜材料。Response characteristics of stannic oxide （SnO2） and niobium pentoxide （Nb2O5） codoped titania （TiO2） as thick film sensors were studied. X-ray diffraction indicates that under proper doping, the TiO2 keeps its rutile phase and its crystal lattice becomes larger. Scanning electron microscope results show that, when the thick film is kept at 1280℃ for a long time （11 h）, the grain of the material will retain an appropriate size. X-ray photoelectron spectroscopy indicates that the low Nb doping induces a high concentration of metal vacancy on the surface of the grain, and the hydrogen response time is very short at a low temperature （300℃）, while the oxygen response time extends quickly at a high temperature （600℃）. When the Nb doping is high, the hydrogen response time becomes long at a low temperature （300℃）, while the oxygen response time is short at a high temperature （600℃）, so it retains stable response characteristics. The results indicate that the material compounding of molar fraction x（Sn）=2.31%, x（Nb）=0.48% could enlarge the crystal lattice parameters properly under the rutile phase, as while as increase the doping concentration, and provide the long-term stability of the titania＇s sensitivity and response under the operating temperature of 300-600 ℃.

关 键 词：氧传感器 二氧化钛 氧化锡氧化铌共掺杂 响应特性 

分 类 号：TQ174[化学工程—陶瓷工业]