Colorimetric Plasmonic Hydrogen Gas Sensor Based on One-Dimensional Nano-Gratings

Plasmonic hydrogen gas sensors have become widely used in recent years due to their low cost, reliability, safety, and measurement accuracy. In this paper, we designed, optimized, fabricated a palladium (Pd)-coated nano-grating-based plasmonic sensor; investigated using the finite-difference time-domain method experimental spectral reflectance measurements, calibrated effects of exposure on mechano-optical properties Pd sensing layer. The nanostructures were DC sputter deposition onto one-dimensional nano-grating optimized with thin-film gold buffer extend optical response dynamic range performance stability; color change sensitivity surface layer was demonstrated for concentrations as 0.5 vol.%, up 4 based resonance wavelength shift within visible band corresponding reversible phase transformation. Visual detection even smallest indicated high sensor. Our technique has potential application high-accuracy portable compatible biochemical smartphones.