electrical and gas - sensing properties of wo3 semiconductor material

... Electrical and gas- sensing properties of WO 3 semiconductor material Wang Yu-De * , Chen Zhan-Xian, Li Yan-Feng, Zhou Zhen-Lai, Wu Xing-Hui Department of Materials Science and Engineering, ... sensors to certain control and monitoring. 3.3. Gas- sensing properties In this study, we ®rst examined the eect of calcining temperature on gas- sensing properties o...

Ngày tải lên: 19/03/2014, 16:48

... oxidizing gases, CO, O 2 and CO 2 , at 600 °C, and a gas mixture (NO 2 + oxidizing gases) with CO, O 2 and CO 2 concen- trations of 1000 ppm, 15% and 10%, respectively. The detection re- sults of the ... The surface and morphological properties of the fabricated sensor were studied, while its gas sensing properties were investigated by detecting NO 2 and other oxid...

Ngày tải lên: 19/03/2014, 16:48

... the effective gas diffusion (Fig. 5). The gas response was improved fur- Fig. 7. Dynamic sensing transients of (a) R30-RH and (b) R30 sensors and (c) gas responses (R g /R a ) of R30-RH and R30 sensors ... hydrothermal synthesis and gas sensing characteristics of WO 3 hollow microspheres Choong-Yong Lee, Sun-Jung Kim, In-Sung Hwang, Jong-Heun Lee ∗ Department of Ma...

Ngày tải lên: 19/03/2014, 16:48

... tungsten oxide films by drop-coating single-crystalline, size-controlled WO 2.72 nanorod solution, and then investigated the dependence of their material and gas- sensing properties on thermal treatment ... the material and gas- sensing properties of room-temperature tungsten oxide nanorod sensors Yong Shin Kim ∗ Department of Applied Chemistry, Hanyang University, An...

Ngày tải lên: 20/03/2014, 13:11

... the best of our knowledge, this is the first report of the selective synthesis of ␣-Fe 2 O 3 superstructures and nanocubes. The gas- sensing properties of the ␣-Fe 2 O 3 superstructures, nanocubes and nanoparticle ... Sensors and Actuators B 141 (2009) 381–389 is one of the most important parameters of sensors. In addition, the sensing properties of hollow sea urch...

Ngày tải lên: 05/05/2014, 15:26

... the band gap of the In- loaded WO 3 . These energetic levels are the source of added support of charge that changes the sensing properties of the WO 3 -based sensors. 4. Conclusions The gas sensing ... Reduc- ing the grain size of active layers is one of the key factors to enhance the gas sensing properties of semiconductor metal oxide sensors [7,8]. Additionally...

Ngày tải lên: 19/03/2014, 16:48

... Research Pro- gram for Materials Technology (Project No. KC 0 2-0 5/0 6-1 0), the research projects of Vietnam Ministry of Education and Training (Code B200 8-0 1-2 17 and B200 8-2 1-0 9) and Key basic ... response time for gas exposure (t 90%(air-to -gas) ) and that for recovery (t 90% (gas- to-air) ) were calculated from the resistance- time data shown in Fig. 3d....

Ngày tải lên: 19/03/2014, 16:48

... Idrissi, Electrical and optical properties of WO 3 thin films, Thin Solid Films 397 (2001) 238–243. [8] W. Yu-De, C. Zhan-Xian, L. Yan-Feng, Z. Zhen-Lai, W. Xing-Hui, Electri- cal and gas- sensing properties ... Au/WO 3 and Pd/WO 3 at T work = 300 ◦ C, and resulting sensing response “S gas ” of the sensors calculated by using the relations: S gas = G gas − G 0 G 0...

Ngày tải lên: 19/03/2014, 16:48

... deal of efforts has been put into developing new sensing materials with improved sensor properties. Of these, n-type semiconducting materials such as SnO , ZnO 2 wx and TiO are promising materials ... S092 5-4 005 00 0051 7-7 () I. Hayakawa et al.rSensors and Actuators B 67 2000 270–274 271 Fig. 1. Change of gas sensitivity with firing temperature. This paper described the...

Ngày tải lên: 19/03/2014, 16:48

... calcinations are in the range of 30–150 nm. The gas sensing properties of these powders in the form of thick film were investigated with and without platinum doping. Gas response of thick films sintered ... achieveimprovements in the gas sensing properties such as enhancing their response, selectiv- ity to a given target species and reduce the operating temperature, sm...

Ngày tải lên: 19/03/2014, 16:48