Optical properties of TiO2@C nanocomposites: Synthesized by green synthesis technique

¹Nanoscience Laboratory, Dept. of Physics, National Institute of Technology, Durgapur, 713209, West Bengal, India

²School of Laser Science and Engg., Jadavpur University, Jadavpur, Kolkata, 700032, West Bengal, India

Adv. Mater. Lett., 2017, 8 (4), pp 449-457

DOI: 10.5185/amlett.2017.1421

Publication Date (Web): Mar 14, 2017

Copyright © IAAM-VBRI Press

E-mail: nitdgpkumbhakar@yahoo.com, pathik.kumbhakar@phy.nitdgp.ac.in

Abstract

In this work, we have reported an eco-friendly and cost-effective technique of synthesis of TiO₂@Carbon nanocomposites (TCNs) material by a facile solvothermal treatment of banana (Musa balbisiana) bract extract. Yellow-green photoluminescence (PL) feature and efficient catalytic activities of green synthesized TCNs have been demonstrated. X-ray diffraction (XRD) data has revealed the simultaneous presence of rutile and anatase phases of TiO₂ in the synthesized TCNs. The presence of amorphous carbon and TiO₂ is also confirmed by Raman spectroscopy. The light emission characteristics of TCNs are studied by PL emission spectroscopy which has confirmed the presence of defect levels caused by oxygen vacancies and surface hydroxyl groups localized within the band-gap. The photocatalytic performance of the synthesized material has been systematically evaluated by observing the degradation of Methylene Blue (MB) dye under the incidence of ultraviolet-visible (UV-Vis)/visible light irradiation and manifested a superior UV-Vis light photo-catalytic activity far over the commercial TiO₂ powder (CTP) under the same experimental conditions. A relatively higher electrochemical performance and 52 times larger cathodic current density is obtained in TCNs in compared to that of CTP. TCNs exhibit extremely high hydrogen evolution reaction catalytic activity with very small onset over potential.

Keywords

Green synthesis, TiO₂-Carbon nanocomposite, optical properties, photoluminescence emission.