Translator Disclaimer
11 April 2019 Hydrogen sensors based on plasmonic nanostructures present on palladium films
Author Affiliations +
Abstract
A highly sensitive and easy-to-fabricate hydrogen sensor based on a plasmonic ‘gold nanowire array on a palladium layer deposited on a metallic substrate' is proposed. Plasmonic waveguide modes are excited in the gaps between the nanowires in this ‘gold nanowire array on a palladium spacer layer deposited on a metallic substrate' system. As incident light is coupled into the plasmonic modes, a dip in the reflectance spectra is observed at the resonant wavelength, i.e., the wavelength at which the incident light is coupled into plasmonic modes. On exposure to hydrogen, the palladium spacer layer transforms to palladium hydride (PdHx), where x, the atomic ratio of H:Pd, increases as the hydrogen concentration increases. This transformation changes the optical properties of the Pd layer, and hence the position of the resonance wavelengths (λres), i.e., the position of the reflection dips in the reflectance spectra of the Au-Pd-Au system, for various concentrations of hydrogen. The difference between the positions of the resonant wavelengths of PdHx and Pd, (λres(PdHx)−λres(Pd)), is used as a measure of the sensitivity of the proposed hydrogen sensor. Analysis of this shift in the plasmon resonance wavelength is done numerically, using Rigorous Coupled Wave Analysis (RCWA) for various values of d, the side length of the nanowires; t, the thickness of the Pd spacer; g, the gap between the adjacent nanowires and θ, the angle of the incident radiation. It is found that, in the presence of hydrogen, the maximum shift in the resonance wavelength for the proposed sensor is ~41 nm as compared to the case when hydrogen is absent. This shift in the resonance wavelength is higher than many currently employed plasmonic Pd-based hydrogen sensors. Thus, the proposed ‘gold nanowire array on a palladium spacer layer deposited on a metallic substrate' is an easy-to-fabricate, selective and sensitive hydrogen sensor.
© (2019) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Yashna Sharma, Mangesh Jaiswal, Rajib Ghosh, and Anuj Dhawan "Hydrogen sensors based on plasmonic nanostructures present on palladium films", Proc. SPIE 11028, Optical Sensors 2019, 110282Z (11 April 2019); https://doi.org/10.1117/12.2524928
PROCEEDINGS
9 PAGES


SHARE
Advertisement
Advertisement
RELATED CONTENT

Nanoplasmonic hydrogen sensing
Proceedings of SPIE (September 09 2014)
Wide bandgap nanowire sensors
Proceedings of SPIE (April 29 2008)
Nanowire growth for sensor arrays
Proceedings of SPIE (October 14 2003)

Back to Top