Authors: | Koo, Youngmi; Malik, Rachit; Alvarez, Noe; Shanov, Vesselin N.; Schulz, Mark; Sankar, Jag; Yun, Yeoheung |
Title: | Free-standing carbon nanotube-titania photoactive sheets |
Type: | Journal Article |
Publisher: | Journal of Colloid and Interface Science |
Year: | 2015 |
Volume: | 448 |
Issue: | 0 |
Start Page: | 148 |
End Page: | 155 |
DOI: | 10.1016/j.jcis.2015.02.022 |
WEB-link: | http://www.sciencedirect.com/science/article/pii/S0021979715001782 |
Abstract: | We report on the development of a new photoactive material via titania (TiO2) nanoparticle deposition on free-standing aligned carbon nanotube (CNT) sheets. Controlling homogeneous dispersion of negatively charged TiO2 nanoparticles, achieved by adjusting pH higher than the point of zero charge (PZC), influenced electrochemical deposition of TiO2 on CNT sheets substrate. Varying deposition time with constant voltage, 5 V allowed different thickness of TiO2 to be deposited layer on the CNT sheets. The thickness and morphology of CNTTiO2 sheets was verified by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS) and X-ray diffraction (XRD). Electrochemical experiments show that diffusion coefficient of Fe ( CN ) 6 3 - was 5.56 ý 106 cm2s1 at pristine CNT sheets and 2.19 ý 106 cm2 s1 at the CNTTiO2 sheets. Photocatalytic activity for CNTTiO2 sheets exhibits high photocurrent density (when deposition time = 30 min, 4.3 ýA cm2 in N2, 13.4 ýA cm2 in CO2). This paper proved a possibility to use CNTTiO2 sheets based on highly-aligned CNT sheets substrate as new photoactive material. |
Keywords: | A. Carbon nanotube sheets, B. Titanium oxide, C. Electrochemical deposition, D. Carbon support, E. Electrocatalysis |