【摘要】 针对被大众所忽视的造纸厂空气污染问题,以其中主要污染成分硫化氢为目标气体,采用液相反应工艺与后续退火工艺相结合的方法制备了α-Fe₂O₃/TiO₂复合纳米气敏传感器。首先,采用XRD,TEM和红外光谱对气敏材料的微观结构和化学组成进行了表征。其次,研究了纳米α-Fe₂O₃/TiO₂气敏传感器对硫化氢气体的气敏性能。研究结果表明,所制备的复合纳米材料纯度较高,以此为基础的纳米α-Fe₂O₃/TiO₂气敏传感器对体积分数为50×10^-6的硫化氢灵敏度为15.6,在120℃的工作温度下,比纯的纳米TiO₂的灵敏度提升到6.8倍,与大多数文献报道的金属氧化物气敏传感器工作温度300℃相比,工作温度下降了60%,传感器的响应与硫化氢浓度之间存在良好的线性关系,同时还具有较快的响应/恢复时间和良好的硫化氢选择性。更多还原

【Abstract】 Since H₂S has been revealed as one of the main gaseous pollutants in the ambient air of pulp and paper mills, a high performance of α-Fe₂O₃/TiO₂ gas sensor for the H₂S detection was developed by a liquid phase reaction process with the subsequent annealing process. Firstly, the microstructure and chemical composition of the synthesized gas sensing materials were characterized by the methods of XRD, TEM and FTIR. Subsequently, the H₂S gas sensing properties of the developed α-Fe₂O₃/TiO₂ nanocomposite sensor were studied. The study results showed that, the compositions of α-Fe₂O₃/TiO₂ were of high purity. Operated at the temperature of 120 ℃, for a volume fraction of 50×10^-6H₂S, the response of the α-Fe₂O₃/TiO₂ gas sensor was 15.6, which was 6.8 times higher than that of the pure TiO₂ material. Compared with the most reported metal oxides gas sensors whose operation temperatures were around 300 ℃, the operating temperature of the developed α-Fe₂O₃/TiO₂ gas sensor was reduced by 60%. Moreover, there was a good linear relationship between the response and the concentration of H₂S, and the developed α-Fe₂O₃/TiO₂ nanocomposite sensor also possessed the fast response/recovery time and excellent H₂S selectivity.更多还原