| 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 energy. Graphene is known to effectively absorb visible light, and due to its high conductivity promote efficient charge transfer. Herein, we present a novel photocatalyst composed of TNTs sensitized with electrodeposited graphene quantum dots (GQDs). GQDs electrodeposition-duration is varied to optimize photocatalytic performance 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 conversionrate of 1.98 ppm·cm−2·h−1, with carbon origin confirmed by 13CO2 isotopic test. |
