采用水热法,在160℃下反应48h制得方块状的WO3纳米孔柱阵列,并使用扫描电镜和X射线衍射仪对样品进行了物相和形貌分析。为验证该材料在湿度感应方面的结构优势,制作了基于单块WO3方块的微型湿度感应器。测试结果显示,在相对湿度为20%~75%的范围内,感应器的电阻几乎随相对湿度的增加而线性减小;感应器对在20%和60%两者间周期性变化的湿度表现出极快速的响应(约2s),且具有良好的稳定性和重复性。分析表明质子导电对该感应器的湿度感应起主要贡献。
Square-like WO3 nanoporous pillar arrays were prepared by a hydrothermal process at 160℃ for 48h.The phase and morphology of the product were characterized by scanning electron microscopy and X-ray diffraction spectroscopy.A micro-humidity sensor based on a single piece of WO3 square was fabricated,for proving the superiority of the as-synthesized material in structure.It was shown that the resistance of the sensor decreased almost in a linear way,with the increase of the relative humidity from 20% to 75%.It was also found that when the relative humidity in atmosphere changed periodically between 20% and 60%,the sensor responded fast(about 2s) with excellent stability and repeatability.Analysis indicated that the protonic conductivity played a leading role in the sensing process of the humidity sensor.