Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
10133676 | Sensors and Actuators B: Chemical | 2018 | 31 Pages |
Abstract
Extremely stable gas sensors at elevated temperature (Tâ>â400â°C) with rapid detection of hydrogen gas are urgently demanded especially for hydrogen production industry which typically involves a high-temperature system. Gallium nitride (GaN) possesses excellent physicochemical properties and is expected to be one candidate for high temperature gas sensor. In this work, the GaN preparation from α-GaOOH precursors by a direct nitridation method under NH3 flow is presented. The nitridation was done at various temperatures to obtain GaN with different oxygen contents, which played a vital role in gas sensing response of thick film GaN in various concentration of H2 gas at 500â°C. The sensitivity of the obtained GaN with 2.07âwt.% of oxygen content was 10 times higher than that sample with the lowest oxygen content (1.9âwt.%) and the sensitivity drastically decreased when the oxygen content was 2.53âwt.%. The sensors also demonstrated high stability as indicated by their repeatable feature after being exposed at a various concentration of H2 (150-750âppm). Furthermore, the GaN showed higher sensitivity than that of β-Ga2O3 sensor.
Related Topics
Physical Sciences and Engineering
Chemistry
Analytical Chemistry
Authors
Angga Hermawan, Yusuke Asakura, Makoto Kobayashi, Masato Kakihana, Shu Yin,