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

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.