Exfoliated MoS₂ Nanosheet/Cellulose Nanocrystal Flexible Composite Films as Electrodes for Zinc Batteries

Abstract

The study presents a more efficient way of exfoliating MoS2 in water and the exfoliated MoS2 was used in an electrode. The electrodes were prepared from exfoliated MoS2 (active material)–nanocrystalline cellulose (binder) with carbon nanotubes (electron-conducting support) and demonstrated in a zinc battery half-cell that showed a Coulombic efficiency of 90%. Successful exfoliation of MoS2 was done by sonication of bulk MoS2 with sulfated cellulose nanocrystals (CNC) for 4 h. The exfoliation was confirmed by Raman and transmission electron microscopy; interestingly, the Raman signals for exfoliated MoS2 show a blue shift for both A1g and E2g 1 bands, which may be an indication of an induced lattice strain effect from the CNC on MoS2. The resulting stable water suspension showed no tendency of precipitation after 2 months of standing. The zeta potential, ζ, for sodium sulfated CNC (CNC–OSO3Na)–MoS2 in water suspension was −45 mV, whereas sulfated CNC (CNC–OSO3H)–MoS2 in water suspension had a zeta potential of −35 mV. The sodium form of sulfated CNCs displayed micelle characteristics, similar to sodium dodecyl sulfate (SDS), with a critical aggregation concentration (CAC) of 1.1 wt %. At CAC, the CNCs efficiently exfoliated MoS2, which is at a much lower concentration than has been reported for synthetic surfactants like SDS and cetyl trimethyl ammonium bromide.

3D Porous MoS2-Decorated Reduced Graphene Oxide Aerogel as a Heterogeneous Catalyst for Reductive Transformation Reactions

“…These results may be observed because of the reduction of various oxygenous moieties from the surface of GO and the weakening of the π electron framework of GO after an interaction with MoS 2 . Additionally, two extra peaks were also observed at ∼379 and ∼404 cm –1 , which are characteristic peaks of the formation of 2H-MoS 2 corresponding to E 2g mode and A 1g mode, respectively. , Additionally, a comparative analysis of the crystal phase of MoS 2 -rGOA before and after the incorporation of MoS 2 was studied using PXRD analysis. The PXRD pattern of GO displayed a well-known diffraction peak located at ∼10.1°, which corresponds to the (001) plane of GO.…”

From Bulk Molybdenum Disulfide (MoS2) to Suspensions of Exfoliated MoS2 in an Aqueous Medium and Their Applications

“…Sonker et al exfoliated the bulk MoS 2 with sulfated cellulose nanocrystals (CNC) in aqueous medium by sonication method and used it as a substrate material into the Zn cell, as shown schematically in Figure c. The Zn/CNC-MoS 2 half cell electrode shows stable voltage efficiency up to 40 cycles and 90% columbic efficiency and the MoS 2 –CNC suspension in aqueous medium used was stable for up to 2 months with no precipitation as shown in Figures d and e . Liu et al fabricated a novel hybrid honeycomb-shaped SC using a Co­(OH) 2 NS-based cathode and a MoS 2 NS-based anode.…”

“…(c) Schematic representation of S Na CNC–MoS 2 composite film as a substrate material for Zn plating in an aqueous electrolyte; cycle stability of Zn plating/striping in 1 M Zn­(Ac) 2 aqueous electrolyte shown by (d) voltage profiles and (e) Coulombic efficiency. [Reproduced with permission from ref , Copyright 2023, American Chemical Society, Washington, DC. ]…”

Fe2O3/Ni Nanocomposite Electrocatalyst on Cellulose for Hydrogen Evolution Reaction and Oxygen Evolution Reaction

“…Interestingly, the incorporation of heteroatoms into modified bio-based materials can also enhance their electrochemical performance. Alternatively, bio-derived materials can be used as binders in electrode materials for various energy and environmental device systems [24,[30][31][32]. Bio-derived materials possessing thickening and binding characteristics are more suitable as binder materials for electrode preparation.…”