Enhanced photocatalytic water splitting of TiO2 by decorating with facet-controlled Au nanocrystals

Localized surface plasmon resonance (LSPR) has drawn much interest in photocatalysis due to the advantages in extending light-absorption and improving charge-separation efficiency. In this work, Au nanocubes with exposed {100} facets and Au nanotrioctahedrons with exposed {221} facets are synthesized via the seed-growth method with the aim of demonstrating the photocatalytic performance under the LSPR effect using a typical TiO2 photocatalyst. The modification of Au nanocrystals results in accelerated charge separation in the TiO2 photocatalyst, which is attributed to the synergetic effect of local electromagnetic field enhancement from the LSPR effect and the Schottky junction established in Au and TiO2. Consequently, the photocatalytic hydrogen-production from the TiO2 photocatalyst is greatly improved. Moreover, Au nanotrioctahedrons modified TiO2 exhibits superior photocatalytic performance due to the stronger local electromagnetic field of the LSPR and the more efficient electron trapping originated from the unique morphology with exposed {221} facets. Published under an exclusive license by AIP Publishing.

Automated summary

This study demonstrates the superior photocatalytic performance of TiO2 under the LSPR effect by synthesizing gold nanocrystals with different exposed facets. The modification of gold nanocrystals accelerates charge separation in TiO2, leading to improved hydrogen production efficiency in photocatalysis.