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近年来,三氧化钨作为一种潜能材料在各种应用领域特别是在气敏传感器方面引起了广泛关注。综述了气敏响应的原理,灵敏度的灵活表示以及目前三氧化钨水热合成和气敏性研究的实验结果。三氧化钨的形貌和结构在很大程度上决定着其气敏性能。由于表面活性区域或体表比的增加能增强利于气体探测的一些性质,所以,晶粒的尺寸有待减小。在众多制备方法中,水热法可以用来制备出各种要求的形貌和结构,且尺寸较小。在水热处理过程中,添加一些辅助试剂还有助于调控三氧化钨的尺寸大小,表面形貌、形状和晶体结构等。大多数关于气体探测的工作都是致力于提高三氧化钨的灵敏度,实现对低浓度气体的探测,扩大探测的气体种类等。事实上,通过优化制备方法,掺杂以及电极的设计等在这些方面都已经取得了很大的成功。但是,得到的这些三氧化钨基气体传感器通常仅能在高于150℃的工作温度下才能发挥出较好的气敏性能。三氧化钨基气体传感器未来研究方向:一方面,寻求新的掺杂材料,使用某些辅助试剂,准确控制制备条件来优化三氧化钨的气敏特性将是人们广泛采用的途径;另一方面,改变探测气体的方式(不测试三氧化钨电学性质的变化),通过记录三氧化钨基传感器光学性质的变化来分析器气敏响应。
In recent years, tungsten trioxide has attracted much attention as a potential material in various fields of application, especially in gas sensors. The principle of gas-sensing response, the flexible representation of sensitivity and the experimental results of the current research on hydrothermal synthesis and gas sensitization of tungsten trioxide are summarized. Tungsten oxide morphology and structure to a large extent determines its gas sensitivity. Since the increase of the surface active area or body surface area ratio can enhance some of the properties conducive to gas detection, the size of the grains needs to be reduced. In many preparation methods, hydrothermal method can be used to prepare a variety of topography and structure, and the smaller size. In the hydrothermal treatment process, adding some auxiliary reagents also help to control the size, surface morphology, shape and crystal structure of tungsten trioxide. Most of the work on gas detection is devoted to the improvement of the sensitivity of tungsten trioxide, the detection of low concentration gas and the expansion of the type of gas to be detected. In fact, we have achieved great success in these areas through optimized preparation methods, doping, and electrode design. However, the resulting tungsten trioxide-based gas sensors typically perform better gas sensing performance only at operating temperatures above 150 ° C. The future of tungsten trioxide-based gas sensors Research directions: On the one hand, the search for new dopant materials, the use of certain auxiliary reagents, and accurate control of the preparation conditions to optimize the gas-sensing properties of tungsten trioxide will be widely adopted; on the other hand , Changing the way of detecting gas (not testing the change of the electrical property of tungsten trioxide), and analyzing the gas sensor’s response by recording the change of the optical property of the tungsten trioxide-based sensor.