Carrier dynamics and the role of surface defects: Designing a photocatalyst for gas-phase CO ₂ reduction

Abstract

Significance In this work, we investigate the role of defects on the electronic and photocatalytic properties of In 2 O 3 - x (OH) y nanoparticles that have been shown to effectively reduce CO 2 to CO via the reverse water–gas shift reaction under light. To understand how such defects affect photogenerated electrons and holes in these materials, we studied the relaxation dynamics of these nanoparticles with varying concentration of defects. This analysis showed that higher defect concentrations result in longer excited-state lifetimes, which are attributed to improved charge separation and correlate well with the observed trends in the photocatalytic activity.