多孔硅基WO_3气敏传感器的制备与性能研究

Study on Preparation and Properties of Porous Silicon/WO_3 Gas Sensor

以钨酸钠和氯化钠为原料,采用水热法在硅基多孔硅上原位生长WO_3纳米棒薄膜,制成p型多孔硅基-n型WO_3复合结构气敏传感器。为了获得最大比表面积的复合形貌,详细研究了水热反应时间和温度对多孔硅基WO_3复合结构显微组织表面形貌的影响。利用扫描电镜、粉末衍射等表征手段测试并分析了多孔硅基表面WO_3纳米棒薄膜的形貌以及晶体结构,并测试了复合结构传感器在不同工作温度下的气敏响应特性,结果表明:该气敏传感器在室温下便对有毒气体NO_2具有高灵敏度以及稳定的重复性。

A novel composite structure of p-porous silicon/n-WO3 was favourably synthesized using sodium tungstate and sodium chloride as raw material and porous silicon as growth substrate by a facile hydrothermal process. In order to maximize specific surface of composite structrue, the influence of reaction time and temperature on appearance and gas sensing performance of samples were studied detailedly. The morphological feature and crystal structure of the WO3 nanorods film grown on porous silicon were characterized by SEM and XRD. Then the dynamic response curves of p-porous silicon/n- WO3 at different working temperatures were tested by a homemade static gas sensing testing system. The experiment results indicate that the sensor as prepared exhibite high response and excellent repeatability at room temperature.