| 초록 |
TiO2 nanotube arrays(TNT) offer an exciting prospect as a photocatalytic material architecture due to the combined properties of high surface area, 1-D vectorial charge transfer, and reduced photogenerated charge recombination. However the TiO2 band gap (≈3.2 eV) limits light absorption to the UV region, which comprises but a small fraction of the solar spectrum energt. Graphene is known to effectively absorb visible light, and due to its high convuctivity promote efficient charge transfer. Herein, we present a novel photocatalyst composed of TNTs sensitized with electro deposited graphene quantum dots (GQDs). GQDs electrodeposition-duration is varied to optimize photocatalytic perfomance of the resulting nanostructured graphene-TNT (G-TNT) films. Under solar spectrum illumination we find optimal G-TNT samples promote a CO2 to CH4 photocatalytic conversion rate of 1.98 ppm cm-2 h-1, with carbon origin confirmed by 13CO2 isotopci test. |
