基于对经过伽马射线照射的氧化钨纳米颗粒的微观结构、电学和气体传感性能的研究

The Research of Microstructural,Electrical and Gas Sensing Properties of Tungsten Oxide Nanocrystals After Irradiated by Gamma Rays

三氧化钨纳米材料(WO3) 由于具有良好的气体传感特性,被广泛应用于工业气体泄露检测和废气处理。WO3纳米颗粒采用溶胶-凝胶法和微波辅助法制备合成,然后经过不同剂量(0、50和100 kGy)60Co伽马射线照射后,形成本研究的实验样品。首先使用透射电镜(TEM)、x射线衍射仪(XRD)和傅里叶变换红外光谱仪(FT-IR)对实验样品的微观形貌和结构进行了表征研究。表征结果表明,伽马射线照射会使WO3纳米颗粒的微观结构发生明显的变化,晶相向三斜晶型转变,颗粒尺寸明显减小。为了研究实验样品的电学性能和气体传感性能,实验样品被作为敏感材料制成了简易传感器,然后通过该传感器分别对NH3、CO2和CO进行敏感特性测试。测试结果表明,经过伽马射线照射后的WO3传感器对NH3的敏感性能降低,对CO2的敏感性能增加,对CO的敏感性能变化不明显。实验结果证实,伽马射线照射使WO3微观结构会发生了变化,能够改变WO3纳米颗粒表面传感层的酸碱特性。因此,伽马射线照射这种可以调整WO3纳米颗粒的传感性能的方法,可以作为一种创新的工艺,以适应不同的应用领域。

Tungsten trioxide nanomaterials (WO3) are widely used in industrial gas leak detection and waste gas treatment due to their good gas sensing properties.In this paper,WO3 nanoparticles was prepared by sol-gel method and Microwave assisted method,and then are exposed to 60Co gamma-rays at different doses (0,50 and 100 kGy) to form the experimental research samples.In this research,transmission electron microscopy (TEM),X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FT-IR) were used to characterize the microstructure of the samples.The characterization results showed that gamma-ray irradiation would significantly change the microstructure of WO3 nanoparticles,transform the crystal phase to triclinic crystal type,and significantly reduce the particle size.In order to study the electrical properties and gas sensing properties of the experimental samples,the experimental samples were made into simple sensors as sensitive materials,and then the sensitive properties of NH3,CO2 and CO were tested through the sensors.The test results showed that,the sensitivity of WO3 sensor to NH3 after gamma-ray irradiation decreased,while the sensitivity to CO2 increased,but the sensitivity to CO did not change significantly.The experimental results confirmed that gamma-ray irradiation changed the microstructure of WO3 nanoparticles,and it would change the acid-base characteristic of the sensing layer on the surface of WO3 nanoparticles.Therefore,gamma-ray irradiation can be used as an effective process method to modify the sensing properties of WO3 nanoparticles in order to adapt to different applications.