An Analysis of Surface Reaction of Gas Sensors
Project/Area Number |
14550053
|
Research Category |
Grant-in-Aid for Scientific Research (C)
|
Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
Applied physics, general
|
Research Institution | Wakayama National College of Technology |
Principal Investigator |
FUJIMOTO Akira Wakayama National College of Technology, Department of Electrical Engineering, Professor, 電気工学科, 教授 (10238610)
|
Project Period (FY) |
2002 – 2003
|
Project Status |
Completed (Fiscal Year 2003)
|
Budget Amount *help |
¥3,000,000 (Direct Cost: ¥3,000,000)
Fiscal Year 2003: ¥1,200,000 (Direct Cost: ¥1,200,000)
Fiscal Year 2002: ¥1,800,000 (Direct Cost: ¥1,800,000)
|
Keywords | gas sensor / smell distinguishing / molecular orbital calculation / 臭い識別 |
Research Abstract |
We have compared experimental results and simulated results for surface reaction on a gas sensor to realize smell distinguishable sensor. Carboxylic acid gases, alcoholic gases and aminic gases were used as sample gases. Heat of formation and surface charge of an SnO_2 cluster and sample gases were estimated as a function of the distance between the cluster and gas molecules by molecular orbital calculation with MOPAC97 package. The calculation results showed that acetic acid gas, a kind of carboxylic acid gas, was adsorbed closer than alcoholic and aminic gases to the SnO_2 cluster surface with a distance of 5 A. Sensitivity of the gas sensor for carboxylic acid gases was higher than that of aminic gases. These results suggested that the adsorption distance from the SnO2 surface strongly affected the sensor sensitivity. We have also measured responses of a gas sensor for several alcoholic gases under modulation of sensor heater. The responses were dependent on kinds of alcoholic gases with different triangular shaped voltage modulation. Delay times of the responses were differing among alcoholic gases. The differences reached the maximum when the sensor was modulated with a triangular voltage with its increasing speed of 43 mV/sec. Four kinds of alcoholic gases, which were methanol, ethanol, propanol and butanol, were distinguished by sensor heater modulation.
|
Report
(3 results)
Research Products
(18 results)