The Photocatalytic Conversion of Carbon Dioxide to Fuels Using Titanium Dioxide Nanosheets/Graphene Oxide Heterostructure as Photocatalyst.

Carbon dioxide (CO) photoreduction to high-value products is a technique for dealing with CO emissions. The method involves the molecular transformation of CO to hydrocarbon and alcohol-type chemicals, such as methane and methanol, relying on a photocatalyst, such as titanium dioxide (TiO). In this research, TiO nanosheets (TNS) were synthesized using a hydrothermal technique in the presence of a hydrofluoric acid (HF) soft template. The nanosheets were further composited with graphene oxide and doped with copper oxide in the hydrothermal process to create the copper-TiO nanosheets/graphene oxide (CTNSG). The CTNSG exhibited outstanding photoactivity in converting CO gas to methane and acetone. The production rate for methane and acetone was 12.09 and 0.75 µmol h g at 100% relative humidity, providing a total carbon consumption of 71.70 µmol g. The photoactivity of CTNSG was attributed to the heterostructure interior of the two two-dimensional nanostructures, the copper-TiO nanosheets and graphene oxide. The nanosheets-graphene oxide interfaces served as the n-p heterojunctions in holding active radicals for subsequent reactions. The heterostructure also directed the charge transfer, which promoted electron-hole separation in the photocatalyst.