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| Abstract: |
| CdFe2O4and its Ag+-doped nano-powders were prepared by sol-gel method, the preparation conditions, phase constituents, microstructures, conductance and gas-sensing properties were also investigated. The results show that Cd1-xAgxFe2O4(0≤x≤0.04) solid solution nano-materials can be obtained when gel powder is calcined for 2h at 800℃, which is made from preheating gels at 350℃for 2hr and gets rid of surviving lemon acid. Measuring conductance shows that the material assumes behavior of the surface-resistance-controlled n-type semiconductor because of ionization of defect AgCd×(→AgCd′+ h·). The positive holes nullify free electrons (h·+ e′→null). The conductance of Ag+-doped solid solution is much lower than that of pure CdFe2O4at same temperature; Sensitivity of the element made from Cd0.98Ag0.02Fe2O4to 45μmol/L C2H5OH is 11 times larger than the petrol interfering gas of same concentration at 330℃. It is hoped to develop a new type information sensitive material of C2H5OH. |
| Key words: Sol-gel method, Cd0.98Ag0.02Fe2O4, AgCd×, C2H5OH, Gas-sensing properties |
| FundProject:安徽省教育厅自然科学基金资助项目. |
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| 银掺杂对CdFe2O4电导和气敏性能的影响 |
|
葛秀涛
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| 摘要: |
| 用溶胶-凝胶法制备了CdFe2O4及其掺银纳米粉,并对其制备条件、物相组成、微结构、电导和气敏性能作了系统研究.结果表明:350℃下预烧2h进一步除尽残存柠檬酸的凝胶粉于800℃下热处理2h可得纯相掺银纳米粉Cd1-xAgxFe2O4(0≤x≤0.04);电导测量显示,该材料呈表面电阻控制的n型半导体导电行为,由于AgCd×电离出的空穴h对材料中导带自由电子的湮灭,使得掺银固溶体的导电性远小于同温下的纯相CdFe2O4;Cd0.98Ag0.02Fe2O4纳米粉制作的元件在330℃下对45μmol/LC2H5OH的灵敏度为相同浓度干扰气体Petrol的11倍多.有望开发为一类新型C2H5OH信息敏感材料. |
| 关键词: 溶胶-凝胶法 Cd0.98Ag0.02Fe2O4 AgCd× C2H5OH 气敏效应 |
| DOI：10.1088/1674-0068/14/4/485-490 |
| 分类号: |