Hydrogen is a renewable energy resource used as a fuel carrier with many advantages for future hydrogen economy systems. However, the safety of handling hydrogen fuel is of great concern due to explosion risks. Thus, in this study, a cost-effective WO3/MoO3-based gasochromic hydrogen sensor having a long-lasting signal (i.e., irreversible color change) is developed for detecting hydrogen leaks. Particularly, the active WO3/MoO3 compound film is deposited on a glass substrate by co-sputtering, and an ultrathin Pd catalyst layer for hydrogen gas decomposition is deposited on it using e-beam evaporation. Various characterizations are conducted to understand the structural, chemical, and optical properties of the WO3/MoO3-Pd films. In general, our WO3/MoO3-Pd sensor has excellent gas discoloration starting from 0.1 % of hydrogen concentration (in dry air) with fast response speed at room temperature. Besides, a DFT study further explains the sensing mechanism of our hybrid WO3/MoO3 structure. Those highlight the potential of our developed sensor for practical hydrogen sensing applications.
Le Thai Duy has worked with Prof. H. Seo\u2019s group at Ajou University after finishing the integrated M.S./Ph.D. program from Sungkyunkwan University in 2017. He was one of the selected candidates for KRF/BP Fellowship in 2018, funded by National Research Foundation of Korea. Currently, he is working as a faculty at Vietnam National University. His current research interest is the development of nanocatalyst and functional materials for wearable sensors and energy devices.
