Flexible hydrogen sensors using graphene with palladium nanoparticle decoration

Abstract Flexible hydrogen gas (H 2 ) sensors are fabricated using a single layer graphene decorated with palladium (Pd) nanoparticles. Thermally evaporated Pd is generally deposited on a graphene in the form of nanoparticles when the deposition thickness is very small. The graphene sensor with Pd thickness of 3 nm exhibits a gas response of ∼33% when exposed to 1000 ppm H 2 and it is able to detect as low as 20 ppm H 2 at room temperature (22 °C). The sensor is so flexible that any significant degradation is not observed when it is bent to a curved geometry with a bending radius of 3 mm. The flexible hydrogen sensors are applicable to a broad range of systems with demanding mechanical flexibility, durability and high gas response.