Surface-Plasmon-Resonance-Enhanced Photoelectrochemical Water Splitting from Au-Nanoparticle-Decorated 3D TiO2 Nanorod Architectures

Abstract

Surface plasmonic resonance (SPR) is a new paradigm in photoelectrochemical (PEC) research that realizes the persistent supply of green energy in a sustainable manner. However, typical approaches for decorating surfaces Au nanoparticles (NPs), such as the colloidal chemical method, nanolithography, and in situ photo/thermal reduction, involve multiple complex steps and often introduce unwanted surface/interface chemicals that jeopardize the SPR effect and charge transport. Herein, we report a largely enhanced PEC performance achieved by decorating Au NPs onto 3D titanium dioxide (TiO2) nanorod architectures grown by surface-reaction-limited pulsed chemical vapor deposition through a one-step sputtering process. The Au NP size and amount could be manipulated in a controlled manner. Compared to pristine TiO2, the Au–TiO2 electrodes achieved high photocurrent density enhancements of 42% and 267% under simulated sunlight and visible-light illumination, respectively. When amorphous aluminum oxide (Al2O3) films...