کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
746278 894450 2006 8 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Pt/GaN Schottky diodes for hydrogen gas sensors
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی آنالیزی یا شیمی تجزیه
پیش نمایش صفحه اول مقاله
Pt/GaN Schottky diodes for hydrogen gas sensors
چکیده انگلیسی

The performance of Pt/GaN Schottky diodes with different thickness of the catalytic metal were investigated as hydrogen gas detectors. The area as well as the thickness of the Pt was varied between 250 μm × 250 μm and 1000 μm × 1000 μm, 8 and 40 nm, respectively. The sensitivity to hydrogen gas was investigated in dependence on the active area, the Pt thickness and the operating temperature for 1 vol.% hydrogen in synthetic air. We observed a significant increase of the sensitivity and a decrease of the response and recovery times by increasing the temperature of operation to about 350 °C and by decreasing the Pt thickness down to 8 nm. Electron microscopy of the microstructure showed that the thinner Platinum had a higher grain boundary density. The increase in sensitivity with decreasing Pt thickness points to the dissociation of molecular hydrogen on the surface, the diffusion of atomic hydrogen along the Platinum grain boundaries and the adsorption of hydrogen at the Pt–GaN interface as a possible mechanism of sensing hydrogen by Schottky diodes.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Sensors and Actuators B: Chemical - Volume 113, Issue 2, 27 February 2006, Pages 797–804
نویسندگان
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