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One-Step Hydrothermal Synthesis of Precious Metal-Doped Titanium Dioxide-Graphene Oxide Composites for Photocatalytic Conversion of CO₂ to Ethanol.

ABSTRACT: We utilized a one-step hydrothermal process for the synthesis of precious metal-doped titanium dioxide (TiO₂)/graphene oxide (GO) composites. The metal-doped TiO₂/GO composites, including silver-TiO₂/GO (Ag-TiO₂/GO), palladium-TiO₂/GO (Pd-TiO₂/GO), and copper-TiO₂/GO (Cu-TiO₂/GO), were synthesized by mixing a metal precursor, titanium butoxide, and graphene oxide in a water-ethanol mixture in an autoclave hydrothermal reactor. The photocatalytic performance of the composites was tested in the photoreduction of carbon dioxide (CO₂) to ethanol. Ag-TiO₂/GO, Pd-TiO₂/GO, and Cu-TiO₂/GO exhibited an ethanol production rate of 109, 125, and 233 μmol/g_cat h, respectively. The outstanding performances of Cu-TiO₂/GO can be attributed to a combined effect of key parameters, including optical band gap, crystallite size, and BET surface area.

SUBMITTER: Lertthanaphol N

PROVIDER: S-EPMC8717584 | biostudies-literature |

REPOSITORIES: biostudies-literature

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