▎ 摘　　要

Palladium decorated reduced graphene oxide/SiO2/Si (Pd-rGO/SiO2/Si) Schottky junction was fabricated by a simple, practical filtration and transfer-printing method. The current-voltage characteristics of the Pd-rGO/SiO2/Si Schottky junction are very sensitive to hydrogen (H-2). An ultrahigh gas response of 970% was achieved using the Schottky junction operated in reverse bias mode at room temperature (RT) for detection of 0.16% H-2, which is much better than that obtained using graphene-based resistance-type H-2 sensors at RT reported previously, due to the junction effect. The gas response enhancement principle demonstrated in this letter can be readily and extensively applied to other graphene-based gas sensing systems. (C) 2014 Elsevier B.V. All rights reserved.