Nanotechnology Enabled Hydrogen Gas Sensing

An important contribution to industry standards and to effective installation of hybrid renewable energy systems is evaluation of hydrogen (H2) monitoring techniques under pilot-scale and/or real-world conditions. We have designed a hybrid system to integrate solar power, electrolysis and hydrogen fuel cell components in a DC micro-grid with capacity to evaluate novel nanomaterials for enhanced H2 gas sensing performance. In general, enhanced hydrogen sensing performance is evaluated by high sensitivity, selectivity and stability as well as low power consumption. Unique properties, such as high surface area to volume ratio, a large number of surface active sites, high specific surface area and reactivity are key attributes of nanomaterials used for gas sensing. These attributes enable sensors to be embedded in Internet-of-Things applications or in mobile systems. With rapid development of hydrogen-based technologies for clean energy applications, there remains a requirement for faster, accurate and selective H2 sensors with low cost and low power consumption. Operating principles for these sensors include catalytic, thermal conductivity, electrochemical, resistance based, optical and acoustic methods. In this paper, we review performance of H2 gas sensors based on conductometric devices operating at room temperature up to 200 °C. The focus of this work includes nanostructured metal oxides, graphene materials and transition metal dichalcogenides employed as sensing materials.