共查询到17条相似文献,搜索用时 187 毫秒
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首先采用射频溅射在单晶硅(Si)上制备氧化锌(ZnO)薄膜,作为生长ZnO纳米棒的晶种层,再在水热条件下生长ZnO纳米棒.X射线衍射、X射线能量色散谱,扫描电镜及室温光致发光谱对样品的物相结构、成分、表面微观形貌和晶体缺陷进行了表征.结果表明合成的ZnO纳米棒是六方纤锌矿结构,长径比较高,结晶良好.研究了ZnO纳米棒/单晶Si传感器在空气和酒精气体中的电压-电流(Ⅰ-Ⅴ)特性,阻抗谱及响应-恢复时间.该传感器在+6 V的偏置电压下,其电阻在0.08 g/L酒精气体中下降71%,响应时间小于1 min,可以作为一种新型的酒精气体传感器. 相似文献
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采用溶胶凝胶法制备的Al掺杂ZnO纳米粉末(AZO)。利用X射线衍射(XRD)和扫描电子显微镜(SEM)表征样品的晶体结构和表面形貌。采用浸渍提拉法将该样品制成旁热式气体传感器,检测其对不同气体的响应恢复特性。结果表明:Al掺杂ZnO表面粗糙,Al的掺杂能够抑制ZnO晶粒增长。当工作温度为70℃、湿度为27%RH时,4.98wt.%Al掺杂ZnO对丙酮气体具有很好的选择性,电阻灵敏度达到了14075,响应和恢复时间分别为1 s和3 s。紫外光照射可明显提高传感器的气敏特性,并降低工作温度。 相似文献
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王晓冬 《电子制作.电脑维护与应用》2014,(13)
本文介绍了一种基于MEMS技术的ZnO气体传感器的设计与制备方案。该传感器采用磁控溅射技术制备掺杂碳纳米管的ZnO薄膜气敏材料,利用干法刻蚀技术形成硅中空膜片,并在膜片上形成Pt环形加热电阻作为微型加热装置。该传感器具有低温敏感、低功耗和小型化等特性。 相似文献
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采用静电纺丝法制备了ZnO纳米纤维材料并使用氧等离子体对其进行表面处理.通过X射线衍射(XRD),扫描电子显微镜(SEM),BET比表面积测试以及X射线光电子能谱分析(XPS)等手段对样品的结构与形貌进行了表征分析.将氧等离子体处理前后的ZnO纳米纤维分别制成气体传感器,对浓度为1×10-6~100×10-6(体积分数)丙酮气体的敏感特性进行了测试分析.测试结果表明,氧等离子体处理后的ZnO纳米纤维响应值较未处理的ZnO纳米纤维有大幅度的提升,最佳工作温度也有所降低,且对甲醛、苯、甲苯、二甲苯等几种干扰气体表现出更好的选择性.从晶粒间势垒和耗尽层厚度等角度初步分析了氧等离子体处理改善ZnO气敏特性的机理. 相似文献
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甲烷(CH4)是电力变压器油纸绝缘中溶解的主要故障特征气体,能有效反映运行变压器油纸绝缘故障.气体传感检测是油中气体在线监测、分析的关键.基于水热法,制备了氧化锌(ZnO)纳米片和纳米球气敏材料及传感元件,基于实验室搭建的微量气体检测平台测试了其对CH4的检测特性.研究表明:基于ZnO纳米片制作的气体传感器比纳米球传感器对CH4表现出更好的气敏性能,对50μL/L CH4的最佳工作温度降低了约60℃,同时对低浓度(1μL/L~20μL/L)CH4表现出较高的线性度和长期稳定性.本研究对研制高性能的ZnO基CH4气体传感器奠定了基础. 相似文献
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以质量分数0.3的In2O3掺杂ZnO电极材料作为敏感电极,Pt为参比电极,在1200℃下烧结制备了(ZnO+质量分数0.3的In2O3)/YSZ/Pt结构的CO传感器。保持O2的体积分数为5%不变,在450℃~550℃下测试其对浓度为2×10-4的CO气体的响应。实验表明,工作温度为500℃时,传感器的响应值达到最大(-59 mV),接近未掺杂之前的两倍,使得传感器的灵敏度得到极大极高。为了克服C3H6气体的干扰(响应值在-50 mV以上),借鉴混合电位理论,用柱状形貌Cr2O3材料替代Pt做参比电极制备了抵偿型CO传感器,并测试其敏感性能。结果表明,该传感器对CO的响应值只减小了-11 mV(为-48 mV),而对C3H6的响应则呈现出大幅度衰减(-10 mV以下),明显提高了传感器的选择性。最后,对此现象,我们采用相应的传感器敏感机理进行了探讨。 相似文献
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Mei ChenAuthor VitaeZhihua WangAuthor Vitae Dongmei HanAuthor VitaeFubo GuAuthor Vitae Guangsheng GuoAuthor Vitae 《Sensors and actuators. B, Chemical》2011,157(2):565-574
Hierarchical flower-like and 1D tube-like ZnO architectures were synthesized by a microemulsion-based solvothermal method. Technologies of XRD, SEM and TEM were used to characterize the morphological and structural properties of the products. The influence of the flower-like and tube-like morphologies on their NO2 sensing properties was investigated. The experimental results showed that high-sensitivity NO2 gas sensors were fabricated. The sensitivity of the tube-like ZnO gas sensor was much higher than that of the flower-like ZnO gas sensor and the tube-like ZnO gas sensor exhibited shorter response time. The in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) technique was employed to investigate the NO2 sensing mechanisms. Free nitrate ions, nitrate and nitrite were the main adsorbed species during the adsorption, and NO also existed in the initial period of surface reoxidation. Furthermore, N2O was formed via NO− and N2O2− stemmed from NO and increased upon rising temperature. Moreover, the PL spectra and the XPS spectra further proved that the intensity of donors (oxygen vacancy (VO) and zinc interstitial (Zni)) and surface oxygen species (O2− and O2) involved in the gas sensing mechanism leaded to the different sensitivities. 相似文献
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Dumbbell-like ZnO microcrystals have been obtained through a facile solution method. The structure, morphology and optical properties of the as-prepared ZnO microcrystals have been characterized by X-ray diffraction, field-emission scanning electron microscopy, transmission electron microscopy and photoluminescence. The as-prepared ZnO microcrystals exhibit excellent sensing properties against acetone at an operating temperature of 300 °C. The response and recovery times are found to be 1.5 and 3 s, respectively. Moreover, the sensor holds the successful discrimination between acetone and ethanol, which makes our product a good candidate in fabricating highly selective sensors in practice. 相似文献
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Jiarui HuangAuthor Vitae Youjie WuAuthor VitaeCuiping GuAuthor Vitae Muheng ZhaiAuthor VitaeYufeng SunAuthor Vitae Jinhuai LiuAuthor Vitae 《Sensors and actuators. B, Chemical》2011,155(1):126-133
Hierarchically three-dimensional (3D) porous ZnO architectures are synthesized by a template-free, economical aqueous solution method combined with subsequent calcination. First, the precursors of interlaced and monodisperse basic zinc nitrate (BZN) nanosheets are prepared. Then calcination of the precursors produces hierarchically 3D porous ZnO architectures composed of interlaced ZnO nanosheets with high porosity resulting from the thermal decomposition of the precursors. The products are characterized by X-ray diffraction, thermogravimetric-differential thermalgravimetric analysis, scanning electron microscopy, transmission electron microscopy, and Brunauer-Emmett-Teller N2 adsorption-desorption analyses. The BET surface area of the hierarchically porous ZnO nanostructures was calculated to be 12.8 m2 g−1. Compared with ZnO rods, the as-prepared porous ZnO nanosheets exhibit a good response and reversibility to some organic gases, such as ethanol and acetone. The responses to 100 ppm ethanol and acetone are 24.3 and 31.6, respectively, at a working temperature of 320 °C. These results show that the porous ZnO architectures are highly promising for gas sensor applications, as the gas diffusion and mass transportation in sensing materials are significantly enhanced by their unique structures. Moreover, it is believed that this solution-based approach can be extended to fabricate other porous metal oxide materials with a unique morphology or shape. 相似文献
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碳纳米管掺杂WO_3气敏元件敏感特性的研究 总被引:5,自引:0,他引:5
研究以碳纳米管(CNT)为掺杂剂制备的CNT-WO3旁热式气敏元件。采用球磨、超声分散的方法对碳纳米管进行分散处理,溶胶—凝胶方法制备WO3微粉,用SEM观察了WO3气敏材料的显微结构,测试了元件对丙酮的气敏性能。结果表明:碳纳米管存在于平均粒径为30~50 nm的WO3晶粒间,从而增加了材料的气孔率。碳纳米管掺杂元件对丙酮的灵敏度远高于纯WO3元件,质量分数为0.4%的掺杂量对丙酮有最高灵敏度,具有能检测低体积分数丙酮气体、选择性好的优点,特别是掺杂碳纳米管明显提高了WO3元件的响应速度。 相似文献