Nanostructured materials for photocatalysis and energy storage devices

Abstract

Graphene oxide (GO) is synthesized by Improved Hummer s newlinemethod. The chemically exfoliated GO sheets contain a large number of newlinecarboxyl, hydroxyl and epoxy groups. These function groups act as an anchor newlinesites for ZnO nanoparticles to embed on to GO layers. The synthesized newlinenanocomposites are then characterized by XRD, SEM and HRTEM. ZnO and newlineZnO-rGO are then used as a photocatalyst to effectively degrade methylene newlinebye and rhodamine B dye solution in an UV reactor. newlineAlso, we tested MoS2 nanosheets as working electrode in lithium newlineion batteries. Vertically aligned (MS-VA) is synthesized by hydrothermal newlinetechnology. MS-VA and purchased horizontally aligned MoS2 (MS-HA) are newlinecharacterized by XRD, SEM, EDX, HRTEM and XPS. The electrochemical newlineproperties of both the sample are performed. Both the nano materials are newlinemixed separately with a binder and carbon black individually to coat them on newlinea copper foil. The copper foil is then cut into 15.8 mm circular discs to use as newlinean anode in coin cell CR2032. Cyclic voltammograms (CV), galvanostatic newlinecharge discharge profile, rate capability and cyclic stability are studied. newlineMS-VA delivers an initial discharge and charge capacity of 873 mAh g-1 and newline574 mAh g-1 respectively. Whereas, MS-HA delivers an initial discharge and newlinecharge capacities of MS-VA of 704 mAh g-1 and 427 mAh g-1. Initial newlineCoulombic efficiency of MS-VA is 65.7% and is higher compared to MS-HA newlinewhich, achieved initial coulombic efficiency of 60.6%. MS-VA exhibited newlinehigher specific capacity, rate capability and better cyclic stability compared to newlineMS-HA. newline newline