Enhanced Mass Transfer by Hydrophobic Pore SiO2 Mask for the Improvement of Methanol Production from CO2 Photoreduction

Abstract

The photocatalytic Carbon dioxide (CO₂) reduction reaction (PCRR) that is, the artificial photosynthesis is a promising route for the clean utilization of renewable resources, but poor selectivity resulting from the competing hydrogen evolution reaction (HER) in aqueous solution limits its practical applicability. However, the conventional polymers enhanced surface method hinder the transfer of charge carriers from catalysts to reactants. Herein, we fabricated a photocatalyst with hydrophobic mesoporous mask. The hydrophobic SiO₂ mask prevents Pt from H₂O and facilitates effective contact between CO₂ (gas) and photocatalyst. Owing to the hydrophobic property of SiO₂ mask, CO₂ gas can be trapped within the channels of the mesopores, thereby promoting the PCRR reaction. The PCRR generation rate of CH₃OH can reach 156.4 µmol·g⁻¹·h⁻¹. This article will provide a new approach for improving CO₂ reduction and selectivity through hydrophobic modification of photocatalysts.