Efficient H_2 production over Au/graphene/TiO_2 induced by surface plasmon resonance of Au and band-gap excitation of TiO_2

摘要

H_2 production over Au/Gr/TiO_2 composite photocatalyst induced by surface plasmon resonance of Au and band-gap excitation of TiO_2 using graphene (Gr) as an electron acceptor has been investigated. Electron paramagnetic resonance study indicated that, in this composite, Gr collected electrons not only from Au with surface plasmon resonance but also from TiO_2 with band-gap excitation. Surface photovoltage and UV-vis absorption measurements revealed that compared with Au/TiO_2, Au/Gr/TiO_2 displayed more effective photogenerated charge separation and higher optical absorption. Benefiting from these advantages, the H_2 production rate of Au/Gr/TiO_2 composite with Gr content of 1.0 wt% and Au content of 2.0 wt% was about 2 times as high as that of Au/TiO_2. This work represents an important step toward the efficient application of both surface plasmon resonance and band-gap excitation on the way to converting solar light into chemical energy.