Pd-gate MOS sensor for detection of methanol and propanol

• Published in: Journal of natural gas chemistry 2011-03, Vol.20 (2), p.123-127
• Main Authors: Pandey, Preeti, Srivastava, J.K., Mishra, V.N., Dwivedi, R.
• Format: Article
• Language: English
• Subjects: Alcohols: methanol, ethanol, etc; Alternative fuels. Production and utilization; Applied sciences; Atomic force microscopy; Cracks; Energy; Exact sciences and technology; Fuels; gas sensor; Gates; Metal oxide semiconductors; Methyl alcohol; MOS structure; MOS结构; Palladium; Scanning electron microscopy; sensitivity; Sensors; 传感器检测; 原子力显微镜; 异丙醇; 扫描电子显微镜; 甲醇反应; 金属氧化物半导体
• ISSN: 1003-9953
• DOI: 10.1016/S1003-9953(10)60165-X

The present paper focused on the detection of methanol and propanol using Pd-gate metal-oxide-semiconductor （MOS） sensor. Surface mor- phology and composition of the gate film were studied by scanning electron microscopy （SEM） and atomic force microscopy （AFM）. The response of the sensor for propanol and methanol was measured as shift in capacitance-voltage （C-V） and conductance-voltage （G-V） curves of the MOS structure. The sensitivity of the sensor towards methanol was found to be greater than that towards propanol. It was 58.2% for methanol and 32% for propanol （at 0.6 V, 1 MHz） in terms of capacitance measurements, while in terms of conductance results the sensitivity was found to be 57.2% for methanol and 38.9% for propanol at 1 kHz. The discontinuities or cracks present in the microstructure of the gate material are believed to be mainly responsible for the high sensitivity of the sensor, going with the decomposition of gas molecules and subsequent hydrogen permeation through Pd.