共查询到17条相似文献,搜索用时 656 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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通过溶剂热法和退火处理制备了不同浓度(0 mol%,2 mol%,5 mol%,10 mol%)PdO修饰的SnO2纳米球.采用X射线衍射仪(XRD)、X射线能谱分析仪(EDS)和扫描电子显微镜(SEM)等测试手段对材料的物相、元素种类和形貌进行了表征,并制成气敏元件,对氢气(H2)进行气敏测试.实验结果表明:5 mol%PdO修饰的SnO2纳米球气体传感器最佳工作温度为175℃,其对100×10-6氢气灵敏度达到19,是纯的SnO2纳米球的灵敏度的3倍.最后,对PdO修饰氧化锡纳米球气体传感器气敏机理进行了分析讨论. 相似文献
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采用水热法合成了纯SnO2和4 mol%Ni掺杂SnO2花状微结构.利用X射线衍射仪(XRD)、X射线能谱分析仪(EDS)和扫描电子显微镜(SEM)对其晶相、成分进行了表征,对制备的纯的和Ni掺杂SnO2传感器性能进行了测试.实验结果表明:Ni掺杂可以显著改善SnO2微结构的气敏特性.在最佳工作温度(280℃)条件下,4 mol%Ni掺杂SnO2传感器对100×10-6甲醇的响应可达到13.0,其响应是纯SnO2气体传感器的2.4倍.同时,其具有快速的响应/恢复时间(6 s/5 s),较低的检测极限(1×10-6),以及对甲醇的良好选择性.最后,对Ni掺杂SnO2气体传感器的气敏机理进行了分析讨论. 相似文献
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采用水热法制备得到铁酸锌(ZnFe2O4)纳米球和纳米片状中空球粉末,利用X射线衍射(XRD)和场发射扫描电镜(SEM)对样品进行了物相分析和形貌观察.利用测试平台检测了两种纳米材料对丙酮的气敏特性,利用铁酸锌纳米片状中空球制备的传感器对丙酮的气敏特性比纳米球更好,在检测范围内(0.8×10-6~500×10-6)表现出更高的灵敏度和较短的响应恢复时间,并具有较好的线性、稳定性和选择性. 相似文献
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《计算机与应用化学》2015,(6)
采用水热法合成了孪连柱状ZnO纳米粉体,通过X射线衍射仪(XRD)、扫描电镜(SEM)、红外光谱仪(IR)和X-射线光电子能谱仪(XPS)等对产物的物相、微观形貌、表面化学键及化学组分进行了表征与分析,并用静态配气法测试了其厚膜型元件的气敏性质,结果表明,产物属于纤锌矿型六方晶系的ZnO,平均直径约300 nm,长约500 nm,其厚膜型元件在工作温度为395℃时对体积分数为100×10-6乙醇和丙酮气体能快速响应,灵敏度分别达到了14.4和29.4,特别是对丙酮气体具有较好的选择性。 相似文献
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利用水热法合成了不同形貌的ZnO基纳米结构气敏材料,利用X射线衍射仪(XRD)和扫描电子显微镜 (SEM)对其进行了结构表征和分析。制备成旁热式气体传感器,测试了其对乙醇(C2H5OH)的气敏特性。实验结果表明:基于ZnO纳米花制作出的传感器比纳米球状传感器对C2H5OH具有更高的灵敏度,在200oC下对50ppm的C2H5OH灵敏度为34.7,是球状ZnO基传感器的1.7倍;两种ZnO基传感器对C2H5OH均表现出较好的重复性,在最佳工作温度下对C2H5OH的响应恢复时间均在15秒以内;最后对ZnO基C2H5OH气体传感器的气敏机理进行了讨论。 相似文献
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张嘉琪胡馨升胡发志等 《传感器与微系统》2014,(4):14-16,20
主要介绍了ZnO纳米棒修饰的石英晶体微天平(QCM)气体传感器的制备与测试。采用两步法在石英晶振片表面制备直径为100 nm的ZnO纳米棒敏感膜,构成QCM NH3传感器。检测系统为自主研发的基于LabVIEW平台的QCM气体传感器频率测试软件。检测NH3的体积分数为5×10-6~50×10-6,响应时间均在10 s以内,最大频差值为10.9 Hz,响应最大频差值与NH3体积分数呈现良好的线性关系。室温条件下,ZnO纳米棒敏感膜可以完全实现吸附解吸过程,具有可逆性。该传感器性能稳定,响应灵敏,具有重复性。 相似文献
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Li LiuAuthor Vitae Shouchun LiAuthor VitaeJuan ZhuangAuthor Vitae Lianyuan WangAuthor VitaeJinbao ZhangAuthor Vitae Haiying LiAuthor VitaeZhen LiuAuthor Vitae Yu HanAuthor VitaeXiaoxue JiangAuthor Vitae Peng ZhangAuthor Vitae 《Sensors and actuators. B, Chemical》2011,155(2):782-788
Pure and Co-doped (0.3 wt%, 0.5 wt%, and 1 wt%) ZnO nanofibers are synthesized by an electrospinning method and followed by calcination. The as-synthesized nanofibers are characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and energy dispersive X-ray (EDX) spectroscopy. Comparing with pure ZnO nanofibers, Co-doped nanofibers exhibit improved acetone sensing properties at 360 °C. The response of 0.5 wt% Co-doped ZnO nanofibers to 100 ppm acetone is about 16, which is 3.5 times larger than that of pure nanofibers (about 4.4). The response and recovery times of 0.5 wt% Co-doped ZnO nanofibers to 100 ppm acetone are about 6 and 4 s, respectively. Moreover, Co-doped ZnO nanofibers can successfully distinguish acetone and ethanol/methanol, even in a complicated ambience. The high response and quick response/recovery are based on the one-dimensional nanostructure of ZnO nanofibers combining with the Co-doping effect. The selectivity is explained by the different optimized operating temperatures of Co-doped ZnO nanofibers to different gases. 相似文献
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Minggang ZhaoAuthor VitaeXinchang WangAuthor Vitae Lingling NingAuthor VitaeJianfeng JiaAuthor Vitae Xinjian LiAuthor VitaeLiangliang CaoAuthor Vitae 《Sensors and actuators. B, Chemical》2011,156(2):588-592
Pure and Cu-doped ZnO nanofibers were synthesized via electrospinning technology. The morphology and structure of the as-synthesized nanofibers were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) and Raman spectroscopy. The effects of Cu doping on H2S sensing properties at low concentration (1-10 ppm) were investigated at 230 °C. The results show that the H2S sensing properties of ZnO nanofibers are effectively improved by Cu doping: 6 at% Cu-doped ZnO nanofibers show a maximum sensitivity to H2S gas, and the response to 10 ppm H2S is one order of magnitude higher than the one of pure ZnO nanofibers. 相似文献
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人体呼气中的丙酮含量可作为糖尿病的标志物.为实现无创糖尿病诊断,设计以金属氧化物半导体气敏传感器阵列为核心的人工嗅觉系统,对完成痕量丙酮的快速检测具有重要意义.通过多个气体流量控制器MFC(Mass Flow Controller)分别配制出模拟糖尿病患者呼气样本(30×10-6丙酮)与另两种干扰气体样本(30×10-6乙醇样本、15×10-6丙酮与15×10-6乙醇混合样本)进行实验,基于BP神经网络算法对3种气体定性识别,并通过主成分分析PCA(Principal Component Analysis)算法对原始的高维特征子集进行降维优化.实验表明:PCA与BP算法相结合,可降低BP神经网络的复杂性、减少预测的误差,同时能够解决单个气体传感器交叉敏感问题,进而提高对气体的选择性.对痕量丙酮样本与另两种干扰气体样本进行分析识别,识别的结果显示:对3种样本的识别准确率为91%.该研究为准确识别糖尿病标志物实现无创诊断技术提供了理论指导. 相似文献
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Copper-doped zinc oxide (ZnO) (1 mol%) nanocrystals were synthesized using a sol–gel method and characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), inductive coupled plasma with optical emission spectrometry (ICP-OES). The XRD result indicated that the introduction of copper had no influence on the crystal structure of ZnO, though ICP-OES exhibited the molar ratio of copper and zinc was 0.86:100. The gas response of the copper-doped ZnO was also studied to ethanol and acetone without and with the illumination of 355 nm light. It was found that the ultraviolet light irradiation could enhance the gas response, and the mechanism with irradiation was discussed. Our results demonstrated that light irradiation was a promising approach to achieve large response at room temperature. 相似文献
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为研究金属离子对金属氧化物半导体的表面敏化作用,以均匀沉淀法制备了ZnO纳米颗粒,并通过金属离子表面微滴注以及二次退火的方法制备出金属离子表面修饰的平面型ZnO气体传感器阵列。并以乙醚蒸汽为目标气体,进行气敏性能测试。发现大部分传感器对乙醚响应性很好,并且经过表面修饰,ZnO的乙醚敏感性能大多得到提升。特别地,Mg2+表面修饰的ZnO膜层展现了最优的气敏性能。X射线光电子能谱和光致发光谱证实,经过Mg2+表面修饰之后,氧空位缺陷浓度明显增加,并且表面羟基基团的数量显著减少,二者的协同作用构成了Mg2+表面修饰ZnO的敏化机制。 相似文献