Chiral Plasmonic Hydrogen Sensors

In this article, a chiral plasmonic hydrogen‐sensing platform using palladium‐based nanohelices is demonstrated. Such 3D chiral nanostructures fabricated by nanoglancing angle deposition exhibit strong circular dichroism both experimentally and theoretically. The chiroptical properties of the palladium nanohelices are altered upon hydrogen uptake and sensitively depend on the hydrogen concentration. Such properties are well suited for remote and spark‐free hydrogen sensing in the flammable range. Hysteresis is reduced, when an increasing amount of gold is utilized in the palladium‐gold hybrid helices. As a result, the linearity of the circular dichroism in response to hydrogen is significantly improved. The chiral plasmonic sensor scheme is of potential interest for hydrogen‐sensing applications, where good linearity and high sensitivity are required. Chiral plasmonic Pd‐based nanohelices for hydrogen sensing. To reduce hysteresis and improve the linearity during hydrogenation/dehydrogenation, Pd‐Au hybrid nanohelices are investigated. Strong circular dichroism responses with excellent signal‐to‐noise ratios are achieved. Such chiral plasmonic sensors are of great interest for hydrogen‐sensing applications, where good linearity and high sensitivity are required.