半导体陶瓷型薄膜气敏传感器的研究进展

半导体陶瓷型薄膜气敏传感器,具有灵敏度高、与气体反应快、制备成本较低等优点,已经成为近年传感器研究和开发的重点．是未来气敏传感器的发展方向之一。本文介绍了陶瓷型半导体薄膜气敏传感器常见的器件结构、薄膜材料的主要制备方法．部分主要的半导体金属氧化物薄膜气敏材料．以及近期相关的研究进展,并扼要分析了今后的发展方向。     

纳米ZnO气敏传感器研究进展

半导体金属氧化物气敏传感器被广泛应用于有毒性气体、可燃性气体等的检测.ZnO是一种重要的半导体气敏材料,特别是纳米ZnO,由于其粒子尺寸小,比表面积大,成为被广泛研究的气敏响应材料之一.简要介绍了纳米ZnO气敏传感器的气敏机理、主要特性,综述了通过新型纳米形貌、结构制备以及元素掺杂改性提升纳米ZnO气敏性能等方面的研究进展,并进一步指出了纳米ZnO气敏传感器研究中存在的问题和未来的研究方向.     

半导体气体传感器新近发展动态

本文简要介绍了国内外半导体气体传感器的生产情况,评述了半导体气体传感器目前发展动向。认为超微粒技术、L-B 膜技术对促进气敏技术很有意义。本文还强调气敏基础研究的重要性,提出从表面和催化伪度出发研究气敏材料是有意义的,并讨论了催化和气敏的关系。     

氧化锌气敏传感器性能的改善及在民航系统的应用

氧化锌是多功能N型半导体材料,具有优良的气敏性能,在气体传感器方面具有广泛的用途。氧化锌气敏材料及测试方法进一步优化后,传感器具有更高的灵敏度和更广泛的适用性。对纳米氧化锌传感器的气敏机理、改善气敏性能的主要方法以及传感器在民用航空方面的应用做了详细的综述。     

碳纳米管及其掺杂氧化物半导体气敏传感器

碳纳米管气敏传感器以其工作温度低和最低检出限较低等优点而备受关注,而碳纳米管掺杂氧化物半导体气敏传感器兼备了氧化物半导体气敏传感器和碳纳米管气敏传感器二者的优点,具有灵敏度较高、最低检出限低和工作温度低等特性。综述了这两类传感器的研究进展,介绍了其气敏机理,并对相应存在的问题及今后的发展趋势进行了概述。     

丙酮气敏传感材料的研究进展

丙酮是一种有毒有害的有机气体,广泛存在于工业生产及家居生活中,同时也是糖尿病的诊断物之一,因此准确实时的丙酮检测手段是安全生产和人体健康所迫切需要的。金属氧化物半导体气体传感器具有灵敏度高、成本低、可靠性高等优点,在有毒有害气体检测领域应用广泛。本文综述了近年来丙酮气敏传感材料的研究进展,对气敏材料的结构与形貌、气敏机理与改性手段等方面进行了介绍,分析了其研究现状以及未来的发展趋势。     

SnO_2复合薄膜甲烷气敏传感器研究进展

甲烷是具有稳定四面体分子结构的碳氢化合物,其键能大、分解困难且活性低,是煤矿安全生产的主要障碍及一种温室气体。SnO2半导体薄膜制备工艺简单、成本低廉、性能稳定,是甲烷传感器研发的主流气敏材料。科技人员进行了很多相关研究以提高传感器的性能,如新气敏材料的研究、催化剂/添加剂的使用、气敏机理的探索、传感器结构改进及气敏膜的表面修饰改性等。本文从气敏膜制备与改性、传感器结构设计及气敏机理研究三个方面,综述了近年来SnO2复合薄膜甲烷传感器的研究进展,结果表明:①应开发复合型金属氧化物半导体及高分子气敏材料,以提高灵敏度、选择性与稳定性;②研发微型智能传感器是未来发展的主要方向,而自组装技术应可用于制备金属氧化物半导体薄膜气体传感器微纳阵列;③气敏机理应与实验测试、材料设计及器件制备进行对照研究。     

我国气体场效应纳米传感器研究获进展

正高灵敏N O传感器的开发是2半导体纳米材料领域的研究热点,而如何选择对气体具有优异响应性能的传感材料是实现对NO高灵敏检测的前提。传感材2料对被测气体响应的大小与其在材料表面的吸附热力学之间有着密切联系,气体在半导体表面的标准摩尔吸附焓代表了气体在半导体表面结合的强弱程度,对气敏传感器的性能具有决定性。因此,在气体传感器研究领域,如何建立标准摩尔吸附焓与传感器响应大小的对应关系,以及如何从传感器测试中获得标准摩尔吸     

TiO2-WO3复合薄膜型气敏传感器性质研究

二氧化钛和三氧化钨是具有重要功能的无机n型半导体材料，常用来制备气敏传感器。本文利用电子束蒸发制备了TiO2-WO3复合氧化畅薄膜，在500℃下退火2h。通过SEM和XRD观察了该薄膜的形貌特性并进行了气敏测试。实验表明，该薄膜对酒精、丙酮和二氧化硫气体具有较强的敏感性。本文还研究了温度、复合浓度和气体浓度对薄膜气体传感能力的影响。     

基于复合金属氧化物的三乙胺气体传感器研究进展

随着市场对有机挥发性气体检测需求的提高,半导体气体传感器因其工作温度低、循环稳定性良好、响应恢复时间短等特性受到了广泛关注。三乙胺是一种重要的化工原料,然而,其挥发性特性及刺激性气味和低毒性对人类的生命安全造成了威胁。近年来国内外有不少三乙胺气体检测的研究论文和产品介绍,但全面性的综述文章极少。本文以前期学者对三乙胺气体检测的工作为抓手,首先讲述了三乙胺传感器的响应机理和提高气敏响应的内在因素,总结了以不同金属氧化物为基质的复合型半导体传感器对三乙胺气体的检测情况,并详细介绍了不同材料形貌与气敏性能之间的关系。另外,对部分材料的气敏增强机理作了简要概述。最终,对三乙胺气体传感领域做出展望,并为后续开展相关领域工作提供了理论基础。     

Influence of electrode material on properties of SnO2-based gas sensor

The influence of electrode material on the properties of oxide semiconductor gas sensor was studied. SnO₂ thick films were printed on top of Au and Pt electrodes on alumina substrate using screen-printing technique. The gap between the electrodes was made narrow (approx. 5 μm) to emphasize the effects, which the electrodes might have on the overall conductance and gas-sensing properties of the sensor, at different temperatures. Laser micromachining was used in the fabrication of the electrode structure with the narrow gap. Temperature-stimulated conductance measurements were carried out in different ambient atmosphere conditions in order to have information about the effects that the electrode materials have on the overall sensor conductance. Many different gases at different concentrations in synthetic air were used in the experiments. It is possible to conclude from the results that the interface between the electrode and sensing material has a very important role for the sensing mechanism of tin dioxide gas sensors.     

纳米SnO2的制备技术及应用

SnO2为N型半导体结构，是一种优良的气敏和湿教材料。介绍了纳米SnO2的主要用途以及电弧气相法、溶胶—凝胶法、水热反应法和机械化学法等制备技术，探讨了SnO2的气敏机理，包括晶体尺寸效应和掺杂效应，并指出了纳米SnO2的发展前景。     

Fabrication of ZIF-8 encapsulated ZnO microrods with enhanced sensing properties for H<Subscript>2</Subscript> detection

As one of the most typical fault characteristic gases in transformer oil, the content of H₂ is an important criterion for judging the operation state of power transformers; while online monitoring of such species through gas sensing technology could effectively detect latent faults and avoid accidents. Zinc oxide is a popular sensing material in recent years with limited sensitivity, selectivity and stability for gas detection, while zeolite imidazolate framework-8 (ZIF-8), one kind of metal–organic frameworks (MOFs) materials, possesses adjustable porosity, huge specific surface areas and good thermal stability, so it could perfectly remedy those defects. This paper studied gas-sensing properties of ZnO rods encapsulated by ZIF-8 (ZnO@ZIF-8) for H₂. The morphologies, structures, and composition were characterized in detail by means of X-ray diffraction, scanning electron microscope, transmission electron microscope, X-ray photoelectron spectroscopy and energy disperse spectroscopy. H₂ gas sensing properties of pure ZnO and ZnO@ZIF-8 composites were implemented based on gas sensing platform. Results suggested that the ZnO@ZIF-8 showed better sensitivity, selectivity and stability than pure ZnO rods, and meanwhile possessed lower optimum operating temperature upon H₂ detection. Meanwhile the gas-sensing mechanism was analyzed comprehensively from three aspects of sensitivity, selectivity and stability. Our aim of this work is to propose a novel core–shell material with enhanced performance for H₂ sensing and provide a new idea for developing high-performance materials to detect fault characteristic gases.     

尖晶石铁酸盐气敏材料的研究进展

尖晶石铁酸盐具有良好的气敏性能,对其制备方法及气敏性能进行了大量研究.综述了尖晶石铁酸盐的结构、制备方法、气敏性能及气敏机理,同时讨论了目前气敏传感器存在的问题并对今后的研究进行了展望.     

Synthesis and NO2-sensing properties of one-dimensional tungsten oxide nanowire bundles

Tungsten oxide nanowires were synthesized by solvothermal method with tungsten hexachloride (WCl6) as precursor. X-ray diffraction, field emission scanning electron microscope and transmission electron microscope characterizations indicated that the as-synthesized nanowires are single phase monoclinic W18O49. With WCl6 concentration increasing, the bundled nanowire became shorter and thicker. The gas-sensing properties of W18O49 nanowire towards NO2 gas were evaluated and the results showed that the optimal gas sensitivity is achieved at 150 degrees C and the thinner nanowire exhibits the higher sensitivity. The results indicate that tungsten oxide nanowire is a promising gas-sensing material for high performance and low power cost NO2 gas sensor.     

A MEMS toolkit for metal-oxide-based gas sensing systems

Silicon micromachining technologies have been used to develop metal oxide gas sensor elements with very small heating power consumption. With the power consumption of a single micromachined sensor element being an order of magnitude less than that of commercial thick-film devices, novel kinds of gas sensing systems become feasible, which allow higher selectivity, lower drift and built-in self-test functionalities to be realised within the power budget of a single thick-film gas-sensing element. Such systems can be built up using components from an emerging MEMS toolkit for miniaturised gas sensing systems. The article presents components of this toolkit and points out system functionalities that can be achieved by combining elements from this kit.     

网状纤维结构氧化镍的制备及其气敏性能

p型半导体金属氧化物作为气敏材料具备响应快速、选择性高的特点,用于气体传感器的制备与开发。静电纺丝法可制备具有丰富气体吸附位点的网状结构材料,增强材料的气体敏感特性。以聚乙烯吡咯烷酮(PVP)、四水合乙酸镍为原料,采用静电纺丝法制备具有网状纤维结构的p型半导体氧化镍。通过X射线衍射、扫描电镜、X射线光电子能谱和比表面积测试等分析技术对材料的结构、形貌、组成和比表面等性能进行表征,并对其气敏性能进行测定,考察煅烧温度对材料气敏性能的影响。结果表明:煅烧温度为500℃时获得的氧化镍组装成气体传感器,在工作温度为250℃时,该元件对50mg/L丙酮气体表现出快速响应特性(响应时间为5s)、良好选择性和稳定性。     

Ce-doped hollow In2O3 nanoboxes derived from metal–organic frameworks with excellent formaldehyde-sensing performance

In recent years, metal oxides derived from metal organic frameworks (MOFs) have been widely used in the gas-sensing direction due to their regular framework structure and large porosity. At the same time, rare earth ion doping can also effectively improve the gas-sensing properties of metal oxide semiconductors. Herein, we report the synthesis of MOFs-drived Ce-doped In₂O₃ samples by calcining precursors prepared by a simple oil bath method. The experimental characterization results show that the as-prepared samples exhibit uniform hollow nanoboxes with high surface area (48.5 m²/g) and abundant oxygen vacancies. Owing to the unique structures, the 1 wt% Ce-doped In₂O₃ nanobox-based gas sensor shows a fast response (1 s), quick recovery (1 s), and an ultralow detection limit (response of 13.4 for 1 ppm of formaldehyde) at the low operating temperature (140 °C). The excellent gas-sensing performance is mainly attributed to hollow structure and the incorporation of Ce, increasing the number of oxygen vacancies and adsorbed oxygen in improving formaldehyde sensing performance of In₂O₃ sensors. This kind of rare earth ion-doped hollow nanoboxes derived from MOFs provides a strategy for the design and development of high performance gas sensor.