The recent market introduction of hydrogen fuel cell cars and the prospect of a hydrogen economy have drastically accelerated the need for safe and accurate detection of hydrogen. In this Letter, we investigate the use of arrays of nanofabricated Pd-Au alloy nanoparticles as plasmonic optical hydrogen sensors. By increasing the amount of Au in the alloy nanoparticles up to 25 atom %, we are able to suppress the hysteresis between hydrogen absorption and desorption, thereby increasing the sensor accuracy to below 5% throughout the investigated 1 mbar to 1 bar hydrogen pressure range. Furthermore, we observe an 8-fold absolute sensitivity enhancement at low hydrogen pressures compared to sensors made of pure Pd, and an improved sensor response time to below one second within the 0-40 mbar pressure range, that is, below the flammability limit, by engineering the nanoparticle size.
- Hydrogen sensing
- Localized surface plasmon resonance
- Plasmonic sensing
- Alloy nanoparticles
Wadell, C., Nugroho, F. A. A., Lidström, E., Iandolo, B., Wagner, J. B., & Langhammer, C. (2015). Hysteresis-free nanoplasmonic pd-au alloy hydrogen sensors. Nano letters, 15(5), 3563-3570. https://doi.org/10.1021/acs.nanolett.5b01053