An In Situ Polymerization‐Encapsulation Approach to Prepare TiO2–Graphite Carbon–Au Photocatalysts for Efficient Photocatalysis

Abstract

AbstractA complex nanoarchitecture composed of TiO2 nanobelts, graphite‐like carbon, and Au nanoparticles (NPs) is developed using an in situ surface polymeric encapsulation technique. The precise arrangement of the carbon layer and Au NPs on a TiO2 surface can be programmed to form three different core@shell structures by simply varying the addition sequence of materials during the encapsulation process. The photocatalytic activity of the three nanoarchitectures is assessed in H2 generation, degradation of dye molecules as well as photoelectrochemical cells under solar and visible light irradiation. In the reaction of H2 generation, no activity can be detected for all samples under visible‐light, while under solar light the sample with Au on the surface of carbon layers wrapped on TiO2 shows the highest activity. By stark contrast, in the photodegradation test, significant difference in activity under visible light is observed, where the sample with Au NPs sandwiched between carbon layers demonstrates the highest activity. All the results indicate that the synergistic effect of carbon‐layers and Au NPs is essential for the catalytic activity enhancement. Moreover, the activity of the photocatalysts is not only highly dependent on the architecture of the catalyst, but also on the type of reaction investigated.