Au-NiO(x)nanocomposite for hot electron-assisted plasmonic photocatalysis

摘要

Nanocomposites of metal-oxide semiconductors containing Au nanoparticles are emerging multifunctional materials for sunlight-driven highly efficient photocatalysis. Here we report a solution-processed nanocomposite synthesis of Au-NiO(x)nanocomposite films by slot-die coating and plotter printing in a straightforwardin situsynthesis approach. Our study demonstrated a significantly enhanced photocatalytic decomposition reaction of MO upon exposure of Au-NiO(x)films to a sunlight simulator. The excellent photocatalytic activity is ascribed to the generation of hot carriers after LSPR excitation in Au NPs. Suitable band alignment between the valence band of NiO(x)and the Fermi level of Au NPs leads to the efficient extraction of the corresponding hot holes by the NiO(x)layer. This results in longer lifetime of the generated hot electrons to drive the photodegradation of methyl orange by generating reactive oxygen species (ROS). We found by free radical capture experiments that O(2)(-)was the major ROS in the photocatalytic reaction.