The discovery of novel antiviral materials is important because many infectious diseases are caused by viruses. Silver nanoparticles have demonstrated strong antiviral activity, and graphene is a potential antimicrobial material due to its large surface area, high carrier mobility, and biocompatibility. No studies on the antiviral activity of nanomaterials on non-enveloped viruses have been reported. To investigate the antiviral activity of graphene oxide (GO) sheets and GO sheets with silver particles (GO-Ag) against enveloped and non-enveloped viruses, feline coronavirus (FCoV) with an envelope and infectious bursal disease virus (IBDV) without an envelope were chosen. The morphology and sizes of GO and GO-Ag were characterized by transmission, scanning electron microscopy, and X-ray diffraction. A virus inhibition assay was used to identify the antiviral activity of GO and GO-Ag. Go-Ag inhibited 25% of infection by FCoV and 23% by IBDV, whereas GO only inhibited 16% of infection by FCoV but showed no antiviral activity against the infection by IBDV. Further application of GO and GO-Ag can be considered for personal protection equipment to decrease the transmission of viruses.

Graphite oxide (GO) photocatalysts derived from graphite oxidation can have varied electronic properties by varying the oxidation level. Absorption spectroscopy shows the increasing band gap of GO with the oxygen content. Electrochemical analysis along with the Mott–Schottky equation show that the conduction and valence band edge levels of GO from appropriate oxidation are suitable for both the reduction and the oxidation of water. The conduction band edge shows little variation with the oxidation level, and the valence band edge governs the bandgap width of GO. The photocatalytic activity of GO specimens with various oxygenated levels was measured in methanol and AgNO3 solutions for evolution of H2 and O2, respectively. The H2 evolution was strong and stable over time, whereas the O2 evolution was negligibly small due to mutual photocatalytic reduction of the GO with upward shift of the valence band edge under illumination. The conduction band edge of GO showed a negligible change with the illumination. When NaIO3 was used as a sacrificial reagent to suppress the mutual reduction mechanism under illumination, strong O2 evolution was observed over the GO specimens. The present study demonstrates that chemical modification can easily modify the electronic properties of GO for specific photosynthetic applications.

The graphene nanosheet electrode with excellent high-rate performance and satisfactory cyclability is an ideal anode for sodium-ion batteries.

The synthesis of a gelled polymer electrolyte (GPE) using poly(ethylene glycol) blending poly(acrylonitrile) (i.e., PAN‐b‐PEG‐b‐PAN) as a host, dimethyl formamide (DMF) as a plasticizer and LiClO4 as an electrolytic salt for electric double layer capacitors (EDLCs) is reported. The PAN‐b‐PEG‐b‐PAN copolymer in the GPE has a linear configuration for high ionic conductivity and excellent compatibility with carbon electrodes. When assembling the GPE in a carbon‐based symmetric EDLC, the copolymer network facilitates ion motion by reducing the equivalent series resistance and Warburg resistance of the capacitor. This symmetric cell has a capacitance value of 101 F g−1 at 0.125 A g−1 and can deliver an energy level of 11.5 Wh kg−1 at a high power of 10 000 W kg−1 over a voltage window of 2.1 V. This cell shows superior stability, with little decay of specific capacitance after 30 000 galvanostatic charge‐discharge cycles. The distinctive merit of the GPE film is its adjustable mechanical integrity, which makes the roll‐to‐roll assembly of GPE‐based EDLCs readily scalable to industrial levels.

Graphene oxide (GO)-based electrochemical capacitors have been fabricated and investigated in 1 M Li2SO4 and Na2SO4 aqueous electrolytes. The GO sheets were derived from natural graphite powders and subsequently coated over carbon paper forming a composite electrode. The GO sheets have highly oxidized planes and edges, occupied by oxygen functionalities including carboxyl, carbonyl, and ether groups. The GO-based capacitor displays specific capacitances of 238.0 and 98.8 F/g at 0.5 mA/cm2 in Li2SO4 and Na2SO4 electrolytes, respectively. The electrochemically active areas for Li and Na ions are calculated to be 452.8 and 219.3 m2/g at the first discharge cycle, respectively. The staking layer of the hydrated Li molecules forms dual layers, whereas the hydrated Na molecules tend toward a monolayer adsorption on the oxidized sheets. On the basis of the Randles plot, the apparent diffusion coefficient of Li+ is calculated to be 3.1 × 10−15 cm2/s, which is about three times higher than that of Na+ in the GO-based electrodes. Compared with the Na2SO4 electrolyte, the GO-based capacitor in Li2SO4 exhibits high stable capacitance, low inner resistance, and high diffusivity. This originates from the smaller ionic size and the lower hydration number, thus facilitating the performance of the capacitor.