TiO2 Nanotube Photonic Crystals Coupled with Gold Nanoparticles for Efficient Visible-Light-Driven Photocatalysis

To achieve highly efficient visible-light photocatalysis, a new composite photocatalyst was designed and constructed for the first time in this study by coupling novel TiO2 nanotube photonic crystals (TiO2 NT PCs) with localized surface plasmon resonance (LSPR) of gold nanoparticles (Au NPs). Due to the synergistic effect of slow photon and LSPR which originated from TiO2 NT PCs and Au NPs respectively, the photocatalyst could expand the light absorption spectrum, thus enhancing photocatalysis efficiency in the visible light region. Compared to its bare TiO2 NT and TiO2 NT PC counterparts, the optimized Au NPs/TiO2 NT PC showed superior performances under the visible light irradiation. Moreover, over 65% Rhodamine B was degraded within 3.5 h by the optimized Au NPs/TiO2 NT PC, while only 15% and 8% Rhodamine B were degraded within the same time by using Au NPs/TiO2 NT and bare TiO2 NT, respectively. We believe that this work will be helpful in designing of PC-coupled plasmonic nanostructure materials for visible-light-driven photocatalysts, as well as other photoelectronic applications, such as photoelectrochemical water splitting and photovoltaic.