Site‐Sensitive Selective CO2 Photoreduction to CO over Gold Nanoparticles

Abstract

AbstractWe demonstrate a new case of materials–gene engineering to precisely design photocatalysts with the prescribed properties. Based on theoretical calculations, a phase‐doping strategy was proposed to regulate the pathways of CO2 conversion over Au nanoparticles (NPs) loaded TiO2 photocatalysts. As a result, the thermodynamic bottleneck of CO2‐to‐CO conversion is successfully unlocked by the incorporation of stable twinning crystal planes into face‐centered cubic (fcc) phase Au NPs. Compared to bare pristine TiO2, the activity results showed that the loading of regular fcc‐Au NPs raised the CO production by 18‐fold but suppressed the selectivity from 84 % to 75 %, whereas Au NPs with twinning (110) and (100) facets boosted the activity by nearly 40‐fold and established near unity CO selectivity. This enhancement is shown to originate from a beneficial shift in the surface reactive site energetics arising at the twinned stacking fault, whereby both the CO reaction energy and desorption energy were significantly reduced.