The Study of Pure and Mn Doped ZnO Nanocrystals for Gas-sensing Applications

International Journal of Bio-Inorganic Hybrid Nanomaterials

مقاله 3، دوره 2، شماره 1، فروردین 2013، صفحه 295-302   

نوع مقاله: Research Paper

چکیده

ZnO and ZnO: Mn nanocrystals were synthesized via reverse micelle method. The structural properties of nanocrystals were investigated by XRD. The XRD results indicated that the synthesized nanocrystals had a pure wurtzite (hexagonal phase) structure. Resistive gas sensors were fabricated by providing ohmic contacts on the tablet obtained from compressed nanocrystals powder and the installation of a custom made micro heater beneath the substrate. Sensitivity (S= Ra/Rg) of ZnO and ZnO: Mn nanocrystals were investigated as a function of temperature and concentration of ethanol and gasoline vapor. The obtained data indicated that optimum working temperatures of the ZnO and ZnO: Mn nanocrystals sensors are about 360°C and 347°C for ethanol vapor and about 287°C and 335°C for gasoline vapor. Based on gas sensing results, although Mn impurity reduces the Sensitivity but the sensor got saturated at much higher gas concentration.

کلیدواژه‌ها

ZnO Nanocrystals؛ Gas sensor؛ Response time؛ Recovery time؛ Micelle method