| Pacific Rim Symposium on Surfaces, Coatings and Interfaces (PacSurf 2018) | |
| Nanomaterials | Wednesday Sessions |
| Session NM-WeP |
| Session: | Nanomaterials Poster Session II |
| Presenter: | Hyonkwang Choi, KwangWoon University, Korea, Republic of Korea |
| Authors: | H. Choi, KwangWoon University, Korea, Republic of Korea W. Yang, KwangWoon University, Korea, Republic of Korea |
| Correspondent: | Click to Email |
TiO2 is one of the most promising catalysts owing to its relatively low cost, superior photocatalytic performance, long-term stability, low cost, and low toxicity under UV illumination.
However, the inherent drawbacks of the TiO2, e.g. the poor response to visible light due to its large bandgap of 3.2 eV, and the fast recombination of photogenerated electron-hole pairs, have significantly impeded the photocatalytic application. To address these matters, the absorption of TiO2 has been extended into the visible range using chemical doping. Nitrogen doping, especially, can alter the band structure or suppress the recombination efficiency of the photogenerated electron-hole pairs, resulting in an enhanced photocatalytic capacity of TiO2 in the visible light region.
We present a facile method to the fabrication of nitrogen-doped GQDs/TiO2 via polyacrylonitrill (PAN)-based carbon fibers (PAN-CFs). Electrospun PAN-CFs have here been selected to produce an electrochemically-active carbon-network matrix containing in-frame incorporated nitrogen, because of its high carbonization yield and high controllable residual nitrogen content. Also, an improvement in visible light absorption is enabled at the GQDs/TiO2 heterostructure due to bandgap narrowing of TiO2 by Ti–O–C bond formed between GQDs and TiO2. PAN plays a dual role, nitrogen doping during its cyclization as well as acting an electrical conducting substrate of a support that enhances the performance of other decorated active catalysts. Thus, nitrogen-doping process of GQDs/TiO2 heterostructure and its corresponding structural and optical properties were investigated through a series of experiments(SEM, TEM, FTIR, XPS, XRD, UV-Vis, PL). We also demonstrate that GQDs/TiO2/PAN electrodes exhibit enhanced photochemical and electrochemical activities advantageous by indoor light methylene blue test and solar-driven hydrogen evolution reaction.