Efficient sunlight driven CO₂ reduction on Graphene-wrapped Cu-Pt/rTiO₂ @ SiO₂

The Photoreduction of CO₂ provides a promising way to solving environmental issues. In this work, hydrogen-doped Titania powders were fabricated using NaBH₄ heated with TiO₂ at 350 °C. The reduced Titania was decorated with Platinum nanoparticles by Poly (N-vinyl-2-pyrrolidone) PVP protected Pt solution. The copper precursor was mixed with the previous sample to get Cu-Pt bi-metal co-catalysts deposited on the surface of reduced TiO₂. After wrapping with graphene oxide (GO) sheets, core-shell-structured photocatalysts graphene-wrapped Cu-Pt/rTiO₂ be synthesized. A systematic study of CO₂ photoreduction performance of graphene-wrapped Cu-Pt/rTiO₂ was conducted using the on-line GC system with SiO₂ fiber as the substrate. Under AM1.5 G simulated sunlight, the graphene-wrapped Cu-Pt/rTiO₂ @ SiO₂ produced carbon monoxide (394.84 μmol g^-1cat 1. h⁻¹) from CO₂ with remarkable selectivity reaching 99%. Over 7 h of illumination period, the prepared sample was showing excellent stability with no decrease in origin CO₂ conversion rate. Elemental mapping and transmission electron microscopy images confirmed Cu-Pt bi-metal nanoparticles deposited on the surface of TiO₂ nanoparticles. The Inert gas control group test confirmed that carbon monoxide products originate from CO₂.