MoS2 nanoflower decorated bio-derived chitosan nanocomposites for sustainable energy storage: Structural, optical and electrochemical studies
Muhammad Rakibul Islam, Homaira, Eashika Mahmud, Rabeya Binta Alam
Abstract
Bio-derived chitosan-molybdenum di sulfide (Cs–MoS 2 ) nanocomposites are prepared by a simple and economical aqueous casting method with varying concentrations of MoS 2 . The structural, surface morphological, optical, and electrochemical properties of the nanocomposites were studied. FTIR analysis reveals the strong interaction between Cs and MoS 2 . FESEM micrograph showed an increment of the surface roughness due to the incorporation of MoS 2 layers into Cs. The surface wettability of the nanocomposites was found to be decreased from 73° to 33° due to the incorporation of MoS 2 into the chitosan. UV–vis spectroscopy study demonstrates a reduction of optical bandgap from 4.29 to 3.44 eV as the nanofiller, MoS 2, introduces localized states within the forbidden energy bandgap. The incorporation of MoS 2 was found to increase the specific capacitance of Cs from 421 mFg −1 to 1589 mFg −1 at a current density of 100 μAg -1 . The EIS analysis revealed an increase in the pseudo-capacitance from 0.09 μF to 4.13 μF and a reduction of charge transfer resistance that comes from the nanofiller contribution. MoS 2 nanoflower introduces more active sites and expands the electroactive zone, thus improving the charge storage property of Cs. The Cs–MoS 2 may offer a new route for the synthesis of eco-friendly, biodegradable, and electrical storage devices.