【作者】 刘如征；

【导师】 全宝富；

【作者基本信息】 吉林大学 ， 微电子学与固体电子学， 2006， 硕士

【摘要】 采用溶胶-凝胶法制备纳米SnO2和In2O3,采用X射线衍射(XRD)、红外光谱(IR)、透射电镜(TEM)等方法,对制得的材料进行分析和表征。通过准确控制溶液PH值、选取适当的烧结温度,制备出晶相单一,结晶度良好的SnO2和In2O3纳米材料。以制备的纳米SnO2和In2O3为基体材料,分别采用La2O3、ZnO、CuO和WO3等作为掺杂剂,研制出灵敏度高,选择性好,稳定性强,响应恢复快的甲醛和甲苯气体传感器。实验结果表明:在SnO2基体材料中共掺杂5wt%ZnO和3wt%La2O3制作的元件对最低检测浓度10×10-6体积分数的甲醛有2倍的灵敏度,而共掺杂5wt%CuO和0.5wt%WO3制作的元件对最低检测浓度30×10-6体积分数的甲苯有3倍的灵敏度。在In2O3基体材料中掺杂5wt%的La2O3对10×10-6和300×10-6体积分数的甲醛分别有4和25倍的灵敏度。同时,还研究了以NASICON作为掺杂剂,研制的甲醛元件,并且发现NASICON的掺入明显的改善了元件的稳定性。更多还原

【Abstract】 In recent years, with the exaltation of the living level along with thepeople, indoors repair increasingly universal. Formaldehyde and toluene whichreleasing from the decorative material has became the main air pollutionindoors. One study showed that the formaldehyde and toluene have themightiness cancer-causing function. Therefore it is necessary to examine theair pollution indoors.This paper began with the synthesization of SnO₂ and In2O3 materialwhich are the basic material mixed mainly with La₂O₃,ZnO,CuO andWO3.This paper researched formaldehyde and toluene sensor with goodsensitivity, selectivity and stability.SnO₂ and In2O3 material was prepared by sol-gel method. XRD、TEMwas used to character the structure and grain size of the resulting materials.The result indicates that by controlling the PH value is 3 and sintertemperature is 500℃pure SnO₂ nanocrystalline can be prepared, and bycontrolling the PH value is 7 and sinter temperature is 500℃pure In2O3nanocrystalline can be prepared.The formaldehyde sensor is based on the SnO₂ nano-powder. The doping3wt%ZnO and5wt% La₂O₃ of can obviously improve the sensitivity of theelement to the formaldehyde. When heat temperature is about 140℃,formaldehyde concentration is 10×10-6, the sensitivity of the element is 2.With the modification of 4A molecule-sifter layer,the selectivity of theelement is improved. The change of the resistance of the element is found tobe within 10% in the 60 days. And the response and recover time of theelement to 10×10-6 formaldehyde gas is 12s and 120s respectively.The toluene sensor is based on the SnO₂ nano-powder The doping of5wt%CuO and 0.5wt%WO3 can obviously improve the sensitivity and stabilityof the element to the toluene. When heat temperature is about 175℃, tolueneconcentration is 30×10-6, the sensitivity of the element is 3. The change of thesensitivity of the element is found to be within 10% in the 90 days. And theresponse and recover time of the element to 30×10-6 Toluene gas is 8s and15s respectively.The formaldehyde sensor is based on the In2O3 nano-powde The dopingof 5wt%La2O3 can obviously improve the sensitivity of the element to theformaldehyde. When heat temperature is about 145 ℃ , formaldehydeconcentration is 10×10-6, the sensitivity of the element is 4. With themodification of 4A molecule-sifter layer,the selectivity of the element isimproved. The change of the Sensitivity of the element is found to be within10% in the 90 days. And the response and recover time of the element to 10×10-6 formaldehyde gas is 10s and 40s respectively.The formaldehyde sensor is based on the In2O3 nano-powder prepared bySol-gel as the basic material mixed with NASICON.10wt% NASICON whichthe cost of x is 2 can obviously improve the sensitivity and stability of theelement to the formaldehyde.The change of the resistance of the element isfound to be within 5% in the 60 days and found the element mixed withNASICON has much better sensitivity to ethanol.更多还原