Development of a Miniaturized Current Type H2 Gas Sensor Based on Nafion and Pt-Pd/C Sensing Electrode

Abstract

In this manuscript, a miniaturized current type gas sensor based on the membrane electrode assemble (MEA) composed of Nafion and Pt-Pd/C sensing electrode was developed to realize the effective detection of H2 at room temperature. The structure of the sensor and the structure of the testing fixture were redesigned. Compared to ordinary current type gas sensors, the new designed sensors were significantly reduced in size, and the details of the new sensor structure were improved. The miniature sensors are easy to carry, install and apply to other devices on a daily basis, with significantly reduced manufacturing costs and allowing the use of precious metals in the selection of gas-sensitive materials. In the experiment, we used Pt and Pd bimetallic stretcher loaded on carbon as sensing material, both noble metals were sensitive to H2 and have high catalytic activity, which could achieve efficient detection of H2 gas. The sensor could detect H2 at levels as low as 3 ppm with a -0.163 nA response and had a good linear relationship in range of 30-6000 ppm H2. In addition, this amperometric H2 sensor displayed fast response-recovery rate as well as excellent selectivity and stability. Within the explosive limits of H2, our sensors enable fast and accurate detection. Such a miniaturized device has a good application prospect due to its advantages.

Keywords: H2 sensor, miniaturized sensor, Pt-Pd/C electrode, Nafion membrane