共查询到17条相似文献,搜索用时 140 毫秒
1.
2.
3.
4.
5.
6.
聚噻吩/WO_3复合纳米材料的制备及气敏性能 总被引:1,自引:1,他引:0
采用水合肼法制备WO3粉体,再以无水FeCl3作氧化剂,通过原位化学氧化聚合制备了不同聚噻吩(PTh)掺杂量的PTh/WO3复合纳米材料。并研究了用其制备的气敏元件的气敏性能。结果表明:气敏元件对H2S和NOx有较高的灵敏度和较好的选择性。用质量分数w(PTh)为5%的PTh/WO3复合纳米材料制备的气敏元件,在加热电压为2.25V时,对体积分数φ(NOx)为5×10–6的灵敏度可达77.14;用w(PTh)为20%的PTh/WO3复合纳米材料所制之气敏元件,在加热电压为2.43V时,对φ(H2S)为20×10–6的灵敏度达63.27。 相似文献
7.
以热氧化钨丝法制备的WO3纳米材料为基材制备了厚膜气敏元件,在常温、紫外光激发条件下实验测试了所制纯WO3气敏元件对不同体积分数的H2S气体的气敏特性曲线,探讨了元件对H2S的灵敏度与紫外光的辐射通量密度的依赖关系。结果表明,常温、无紫外光照下WO3气敏元件对H2S不敏感,而在常温及紫外光激发下WO3气敏元件对H2S的灵敏度显著增大,且随着紫外光辐射通量密度增加,元件对H2S的灵敏度先增大而后减小。 相似文献
8.
9.
采用溶胶-凝胶法制备了CuO掺杂TiO_2纳米材料并用于丙酮气敏传感器制备,通过XRD和SEM对样品的物相结构和表面微观形貌进行表征,利用EDS对样品的元素种类与平面分布进行了分析,研究了CuO掺杂量、工作温度、光激发等对元件气敏性能的影响。结果表明,CuO-TiO_2对丙酮表现出良好的选择性,掺杂6.6%(质量分数)CuO的CuO-TiO_2,经500℃退火后,在75℃下,对体积分数为1000×10~(-6)丙酮的灵敏度达到106.71,响应时间和恢复时间均为2 s;同时研究还显示光激发可以有效提高元件的气敏性能,紫外光照射下元件对丙酮的灵敏度相比无光条件下增幅95%,而可见光照射下元件对丙酮的灵敏度相比无光条件下仍能增幅50%。 相似文献
10.
《电子元件与材料》2015,(9):35-39
用过硫酸铵作为氧化剂,通过界面聚合法制备纳米聚苯胺,并进一步通过水热法制备了纳米WO3/聚苯胺复合材料。通过XRD、FTIR、TG-DTA、SEM等手段对不同聚苯胺掺杂(质量分数为1%,5%,10%)的WO3/聚苯胺复合材料进行了表征,并进行了气敏性能研究。结果显示,合成的球状纳米WO3包覆棒状聚苯胺核-壳结构复合材料主晶相为正交晶系,晶粒大小约为20 nm;掺杂质量分数10%的聚苯胺后,主晶相变为六方晶系,晶粒大小为15 nm左右。复合材料的分解温度提高到262℃左右。气敏性能研究表明,复合材料在室温对三甲胺显示出较好的气敏性能,对体积分数200×10–6的三甲胺的灵敏度达到4.8。 相似文献
11.
In the present study, UV light activated gas sensor was investigated for Al/Al2O3/p-Si and Al/TiO2/Al2O3/p-Si samplesby atomic layer deposition method (ALD). Generally, in order to obtain the sensing performance, traditional metal oxide semiconductor gas sensors are operated at 100–400 °C. However, this temperature range limits their applications to flammable gases, and causes high power consumption. It is important to note that sensing performance experiments should have been performed at room temperature. With the support of UV light, gas sensors do not need to be heated and they can work at room temperature easily. For this purpose, electrical measurements have been performed on sensing performance with and without UV irradiation for dedection of NO2 gas. With the help of UV irradition, we obtained good sensitivity at the room temperature for Al/TiO2/Al2O3/p-Sistructure but under the same conditions no result was obtained for Al/Al2O3/p-Si structure. Without UV irradiation, there was no sensitivity for both.We observed that increasing of sensitivities at the room temperature show a direct effect of the light on the adsorbed oxygen ions. According to the relation of photocatalytic reaction and photoactivated gas sensing process, we concluded that TiO2 might be an acceptable sensor for detection of nitrogen dioxide (NO2) at room temperature under UV illumination. 相似文献
12.
The gas-sensing properties of titanium oxide (TiO2)-doped zinc oxide (ZnO) thick film sensor specimens to typical ethanol vapor under UV light activation at room temperature have been investigated. Zinc nanoparticles were mixed with commercial TiO2 in various weight percentage (0%, 1%, 5%, and 10%) and sintered at 650 °C for 2 h to prepare the thick film sensors. The sensors exhibit better photosensitivity and gas sensitivity to ethanol analyte. The response and recovery times are within 8 s. TiO2 doping can improve the sensors stability and reproducibility. X-ray diffraction (XRD) and scanning electron microscopy (SEM) characterization of the film materials revealed that Zn2TiO4 and TiO2 phases hindered the rod- or needle-like structure growth and subsequently affected the gas sensitivity. UV absorption spectra of the sensing film material completely dispersed in ethanol solution exhibited that the red shifts were caused with the doping of a small amount of TiO2 into ZnO then blue shift was caused with higher TiO2 level. The results of the UV spectra are well consistent with the photosensitive performance. The maximum sensitivity can be achieved by doping the amount of TiO2 (5 wt%). 相似文献
13.
14.
Hongping Liang Xin Guo Lanpeng Guo Siying Liu Qiuqiang Zhan Haihong Yang Hao Li Nicolaas Frans de Rooij Yi-Kuen Lee Paddy J. French Yao Wang Guofu Zhou 《Advanced functional materials》2023,33(21):2215099
Constructing near-infrared light (NIR) light-enhanced room temperature gas sensors is becoming more promising for practical application. In this study, learning from the structure and photosynthetic process of chlorophyll thylakoid membranes in plants, the first “Thylakoid membrane” structural formaldehyde (HCHO) sensor is constructed by matching the upconversion emission of the lanthanide-doped upconversion nanoparticles (UCNPs) and the UV–vis adsorption of the as-prepared nanocomposites. The NIR-mediated sensor exhibits excellent performances, including ultra-high response (Ra / Rg = 2.22, 1 ppm), low practical limit of detection (50 ppb), reliable repeatability, high selectivity, and broadband spectral response. The practicality of the NIR-mediated gas sensor is confirmed through the remote and external stimulation test. A study of sensing mechanism demonstrates that it is the UCNPs-based light transducer produces more light-induced oxygen species for gas response in the process of non-radiative/radiative energy transfer, playing a key role in significantly improving the sensing properties of the sensor. The universality of NIR-mediated gas sensors based on UCNPs is verified using ZnO, In2O3, and SnO2 systems. This work paves a way for fabricating high-performance NIR-mediated gas sensors and will expand the application fields of NIR light. 相似文献
15.
分别用钨酸钠或钨酸铵溶液及浓盐酸作原料,用直接沉淀法制备了含Na+和不含Na+的WO3粉体,并用XRD及粒度分布测试仪对其进行了表征。结果表明:产物分别是WO3/Na2W4O13混合氧化物及纯WO3,前者的平均粒径为4.459μm,后者为1.366μm。气敏测试结果表明:含Na+的WO3/Na2W4O13气敏元件对体积分数为50×10–6的H2S的灵敏度是164,恢复时间为35s。纯WO3气敏元件对体积分数为50×10–6的NO2及Cl2的气敏性能较好,其灵敏度分别为468与1635。 相似文献
16.
High Performance Three‐Dimensional Chemical Sensor Platform Using Reduced Graphene Oxide Formed on High Aspect‐Ratio Micro‐Pillars
下载免费PDF全文
![点击此处可从《Advanced functional materials》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Le Thai Duy Duck‐Jin Kim Tran Quang Trung Vinh Quang Dang Bo‐Yeong Kim Hock Key Moon Nae‐Eung Lee 《Advanced functional materials》2015,25(6):883-890
The sensing performance of chemical sensors can be achieved not only by modification or hybridization of sensing materials but also through new design in device geometry. The performance of a chemical sensing device can be enhenced from a simple three‐dimensional (3D) chemiresistor‐based gas sensor platform with an increased surface area by forming networked, self‐assembled reduced graphene oxide (R‐GO) nanosheets on 3D SU8 micro‐pillar arrays. The 3D R‐GO sensor is highly responsive to low concentration of ammonia (NH3) and nitrogen dioxide (NO2) diluted in dry air at room temperature. Compared to the two‐dimensional planar R‐GO sensor structure, as the result of the increase in sensing area and interaction cross‐section of R‐GO on the same device area, the 3D R‐GO gas sensors show improved sensing performance with faster response (about 2%/s exposure), higher sensitivity, and even a possibly lower limit of detection towards NH3 at room temperature. 相似文献
17.
La_2O_3掺杂WO_3纳米粉体的制备及气敏性能 总被引:1,自引:0,他引:1
以胶溶法制备的WO3和sol-gel法制备的La2O3为原料,采用固相研磨法制备了掺杂剂质量分数w(La2O3)为0.5%~7.0%的La2O3-WO3纳米粉体,利用XRD、TEM等测试手段分析了粉体的微观结构,采用静态配气法测试了由所制粉体制成的气敏元件对丙酮的气敏性能。结果表明,制得的La2O3-WO3纳米粉体结晶良好,平均粒径为60nm;当工作电压为4.5V,w(La2O3)为5.0%时,粉体在600℃下烧结制得的气敏元件对体积分数为50×10–6的丙酮的灵敏度可达37.6,响应时间和恢复时间分别是1s和11s。 相似文献