Photo-driven synthesis of polymer-coated platinized ZnO nanoparticles with enhanced photoelectrochemical charge transportation

Incorporation of both metal nanoparticles and a polymer layer is proposed to benefit charge transport in a semiconductor in the absence of electron and hole scavengers. Therefore in this work, zinc oxide is deposited with platinum metal and a layer of polymeric species via a photocatalytic route: platinum cation photoreduction and phenol photooxidative polymerization which utilize photogenerated electrons and holes of ZnO, respectively. The photoelectrochemical performances of these photocatalysts follow the order of Poly/Pt/ZnO > Pt/ZnO > bare ZnO, revealing the effectiveness of both the platinum and polymer in enhancing charge separation within ZnO. Although platinum is known to be an excellent electron sink for promoting electron transfer, the performance of Pt/ZnO was limited by the transport of holes to the ZnO surface for oxidation reactions. Thus, the polymer layer plays an important role in facilitating hole transport, resulting in the enhanced performance of Poly/Pt/ZnO.