In this work, holey reduced graphene oxide (HRGO) was synthesized by the deposition of silver (Ag) nanoparticles onto the reduced graphene oxide (RGO) sheets followed by nitric acid treatment to remove Ag nanoparticles by microwave irradiation to form a porous structure. The HRGO were characterized by X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), ultra violet-visible spectroscopy (UV-Vis), thermogravimetric analysis (TGA), and Raman spectroscopy. These novel HRGO exhibited high rate capability with excellent cycling stability as an anode material for lithium-ion batteries. The results have shown an excellent electrochemical response in terms of charge/discharge capacity (423 mAh/g at 100 mA/g). The cyclic performance was also exceptional as a high reversible capacity (400 mAh/g at 100 mA/g) was retained for 100 charge/discharge cycles. This fascinating electrochemical performance can be ascribed to their specific porous structure (2–5 nm pores) and high surface area (457 m2/g), providing numerous active sites for Li+ insertion, high electrical conductivity, low charge-transfer resistance across the electrolyte–electrode interface, and improved structural stability against the local volume change during Li+ insertion–extraction. Such electrodes are envisioned to be mass scalable with relatively simple and low-cost fabrication procedures, thereby providing a clear pathway toward commercialization.
The present study reports, high-performance polymer absorbents for crude oil and organic solvents based on 3D cross-linked polystyrene-polymethyl methacrylate/divinyl benzene (PS-PMMA/DVB). The preparation of the 3D crosslinked polymer absorbents has been carried out by bulk polymerization method using styrene (S) and methyl methacrylate (MMA) monomers in the presence of DVB with azobisisobutyronitrile as an initiator. The prepared cross-linked polymer absorbents were characterized by Fourier transform infrared spectroscopy, thermogravimetric and differential scanning calorimetry, and dynamic mechanical analyses. The absorption kinetics, thermodynamics of the absorption process as well as the recyclability of the cross-linked polymer absorbents were investigated in detail. The developed 3D cross-linked PS-PMMA/DVB absorbents have demonstrated excellent absorption capacities for both organic solvents and crude oil. For instance, the developed polymer absorbent (PS-PMMA/DVB [1 wt%]) shows a maximum absorption capacity of 12 g/g for chloroform , 6 g/g for tetrahydrofuran, and 3 g/g for crude oil. The absorption capacities by the polymer absorbents show a direct relationship with the polarity of the solvents. Moreover, the change of absorption capacity after several repeated cycles of absorption/desorption was only marginal. The demonstrated absorption capacities and the excellent recyclability make polymer absorbents as potential candidates for the oilfield applications and produced water treatments.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.