Graduate School of Engineering, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki 852-8521, Japan.
Institute of Physical and Theoretical Chemistry, Eberhard Karls University of Tuebingen, Tübingen D-72076, Germany.
ACS Sens. 2021 Nov 26;6(11):4019-4028. doi: 10.1021/acssensors.1c01412. Epub 2021 Oct 25.
Gas adsorption properties of semiconductor-type gas sensors using porous (pr-) InO powders loaded with and without 0.5 wt % Au (Au/pr-InO and pr-InO sensors, respectively) at 100 °C were examined by using diffuse reflectance infrared Fourier transform spectroscopy, and the effect of the Au loading onto pr-InO on the NO-sensing properties were discussed in this study. We found the following: the resistance of the Au/pr-InO sensor in dry air is lower than that of the pr-InO sensor; the DRIFT spectra of both the sensors show a broad positive band between 1600 and 1000 cm in dry air (reference: in dry N at 100 °C), which mainly originates from oxygen adsorbates and/or lattice oxygen, and that this band is much larger for the Au/pr-InO sensor than for the pr-InO sensor; the Au loading also increases the adsorption amount of HO and the reactivity of NO on the pr-InO surface; and the NO response of the Au/pr-InO sensor in dry air is marginally higher than that of the pr-InO sensor in the examined concentration range of NO (0.6-5 ppm) in dry air. The obtained results strongly support the enhancement of the NO adsorption onto the pr-InO surface by Au loading, which contributed to the improvement of the NO-sensing properties.
采用漫反射红外傅里叶变换光谱法研究了在 100°C 下负载和未负载 0.5wt%Au（分别为 Au/pr-InO 和 pr-InO 传感器）的多孔（pr-）InO 粉末对半导体型气体传感器的气体吸附性能，并在本研究中讨论了 Au 负载对 pr-InO 的 NO 传感性能的影响。我们发现：在干燥空气中，Au/pr-InO 传感器的电阻低于 pr-InO 传感器；两种传感器的 DRIFT 谱在干燥空气中（参考：在 100°C 的干燥 N 中）在 1600 至 1000cm 之间显示出一个宽的正带，主要来源于氧吸附物和/或晶格氧，并且 Au/pr-InO 传感器的带比 pr-InO 传感器的带大得多；Au 负载还增加了 pr-InO 表面上 HO 的吸附量和 NO 的反应性；在干燥空气中，Au/pr-InO 传感器在 0.6-5ppm 范围内的 NO 响应略高于 pr-InO 传感器的响应。研究结果强烈支持通过 Au 负载增强 pr-InO 表面对 NO 的吸附，这有助于提高 NO 传感性能。
