摘要
用反滴定化学共沉淀法制备了纳米尺寸尖晶石型的复合金属氧化物MgFe_2O_4粉体。用X射线粉末衍射分析、透射电镜等手段研究了其结构特性。MgFe_2O_4粉体颗粒均匀，700℃煅烧1 h粉体平均粒径约为20 nm。研究表明：煅烧温度对材料的结构及性能有较大的影响。以MgFe_2O_4纳米粉体为原料制备了旁热式气敏元件，测试了元件的敏感特性和响应恢复特性。结果显示，MgFe_2O_4是一种良好的n型半导体气敏材料，700℃煅烧1 h所得纳米粉体制作的元件在300℃工作温度时对CH_3COCH_3有较高灵敏度和良好的选择性，对体积分数为1 000×10_(-6)的CH_3COCH_3的灵敏度可达36.87。并对气敏机理给予了解释。
MgFe2O4 composite oxide nano-powder of spinel-type was prepared by inverse titrating chemical co-precipitation method, and its microstructure was characterized by means of powder XRD and TEM. The powder with homogeneous grain size of about 20 nm of average diameter was obtained after calcining at 700°C for 1 h. The results show that sintering temperatures have great influence on microstructure and properties of the sample. The properties of MgFe2O4 gas sensors made from MgFe2O4 nano-powder were measured. MgFe2O4 is an excellent n-type semiconductor gas-sensing material, and the sensor prepared by MgFe2O4 powder calcined at 700°C for 1 h exhibits high sensitivity and good selectivity. The sensitivity of the sensor to CH3COCH3 1000 × 10-6 in volume at 300°C operating temperature can reach to 36.87. The gas sensing mechanism is discussed.
出处
《硅酸盐学报》
EI
CAS
CSCD
北大核心
2004年第12期1491-1495,共5页
Journal of The Chinese Ceramic Society
基金
云南省科技厅中日国际合作项目(95E007)
关键词
镁铁复合氧化物
反滴定化学共沉淀
气敏性
丙酮
Acetone
Grain size and shape
Iron compounds
Magnesium compounds
Microstructure
Nanostructured materials
Precipitation (chemical)
Sintering
