Wafer-scale synthesis of graphene by chemical vapor deposition and its application in hydrogen sensing

Graphene with a large area was synthesized on Cu foils by chemical vapor deposition under ambient pressure A 4 '' x 4 '' graphene film was transferred onto a 6 '' Si wafer with a thermally grown oxide film Raman mapping indicates monolayer graphene dominates the transferred graphene film Gas sensors were fabricated on a 4 mm x 3 mm size graphene film with a 1 nm palladium film deposited for hydrogen detection Hydrogen in air with concentrations in 00025-1% (25-10,000 ppm) was used to test graphene-based gas sensors The gas sensors based on palladium-decorated graphene films show high sensitivity, fast response and recovery, and can be used with multiple cycles The mechanism of hydrogen detection is also discussed (C) 2010 Elsevier B V All rights reserved