A promotional effect of surface plasmon resonance (SPR) on direct hydrogen peroxide (H2O2) formation from H-2 and O-2 over a structure-controlled Pd-Au catalytic system is reported herein. Pd NPs supported on reduced graphene oxide (rGO) layer-coated Au nanorod (NR) nanocomposite catalysts were synthesized, and the structure was confirmed by multiple characterization techniques. H2O2 production is highly enhanced under visible light irradiation in the direct H2O2 formation from H-2 and O-2. The H2O2 decomposition test and the H-2-D-2 exchange reaction reveal that the SPR of Au NRs facilitates H-2 activation on the Pd NP surface, leading to efficient H2O2 production. Furthermore, the rGO layer not only functions as an electron mediator in the catalytic reaction, but also contributes to the control of Pd NP sizes in the catalyst synthesis. (c) 2020 Elsevier Inc. All rights reserved.