Hydrogen sensors are important not only in producing, storing, and handling hydrogen fuel but also in using hydrogen-powered devices. However, there are various challenges for practical use and commercialization of gas sensors such as (i) the cost reduction of materials for mass production, (ii) the sensitivity of the sensors towards a wide concentration range of analyte gas, and (iii) the stability of the sensors, especially in high humidity levels. For the first two objectives, our miniaturized resistive sensor based on a multilayered Pd-Ni nanocatalyst is developed. Our Pd-Ni sensors possessed excellent hydrogen sensitivity from 20 ppm to 100 % at room temperature. To solve the problem of humidity interference, polytetrafluoroethylene (PTFE) and titanate (TiOx) are used for passivating the sensors. With passivation, our sensors can operate well under high relative humidity conditions of up to 85 % RH at operating temperatures ≤ 80 °C. More importantly, the passivated Pd-Ni sensors are produced using dry methods (e-beam evaporation and sputtering), which are highly applicable in industrial-scale manufacturing.
Dr. LT Duy has worked with Prof. H. Seo’s 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. His current research is the development of nanocatalysts and functional materials for wearable sensors and energy devices.This work was supported by the Korea Energy Technology Evaluation and Planning (Project No: 20203030040030 ) by Ministry of Trade, Industry and Energy, Republic of Korea and the Korea Electric Power Research Institute (Project No: R21XO02-1 ), Republic of Korea.
