New Nanocomposites Based on Li–Fe–Mn Double Spinel and Carbon Self-Doped Graphitic Carbon Nitrides with Synergistic Effect for Electrochemical Hydrogen Storage Application

Decoration of green synthesized S, N-GQDs and CoFe2O4 on halloysite nanoclay as natural substrate for electrochemical hydrogen storage application

Halloysite nanotubes (HNTs) with high active sites are used as natural layered mineral supports. Sulfur- and nitrogen-co doped graphene quantum dots (S, N-GQDs) as conductive additive and CoFe2O4 as the electrocatalyst was decorated on a HNT support to design an effective and environmentally friendly active material. Herein, an eco-friendly CoFe2O4/S, N-GQDs/HNTs nanocomposite is fabricated via a green hydrothermal method to equip developed hydrogen storage sites and to allow for quick charge transportation for hydrogen storage utilization. The hydrogen storage capacity of pure HNTs was 300 mAhg-1 at a current density of 1 mA after 20 cycles, while that of S, N-GQD-coated HNTs (S, N-GQDs/HNTs) was 466 mAhg-1 under identical conditions. It was also conceivable to increase the hydrogen sorption ability through the spillover procedure by interlinking CoFe2O4 in the halloysite nanoclay. The hydrogen storage capacity of the CoFe2O4/HNTs was 450 mAhg-1, while that of the representative designed nanocomposites of CoFe2O4/S, N-GQDs/HNTs was 600 mAhg-1. The halloysite nano clay and treated halloysite show potential as electrode materials for electrochemical energy storage in alkaline media; in particular, ternary CoFe2O4/S, N-GQD/HNT nanocomposites prove developed hydrogen sorption performance in terms of presence of conductive additive, physisorption, and spillover mechanisms.

Introducing of Li2FeMn3O8 /C-C3N4 /IL nanocomposite for electrochemical determination of pantoprazole sodium in real samples

A new electrochemical sensor based on Li₂FeMn₃O₈/C-C₃N₄ (LFMO/CCN)/1-ethyl-3-methylimidazolium chloride modified carbon paste electrode (CPE) has been constructed to measure pantoprazole sodium (PNZS). The electrochemical impedance spectroscopy (EIS) method was employed to evaluate the electrode charge-transfer resistances. Moreover, the differential pulse voltammetry method was used to detect PNZS in phosphate buffer solution (PBS) at pH 7.0. The detection limit of 80.0 × 10^-9 M and 10.9 × 10^-7 M was obtained under optimal conditions in the linear concentration range of PNZS 0.09-100 μM and 100-900 μM. Chronoampermetry technique was utilized to determine the diffusion coefficient (D) of PNZS on the modified electrode surface. The CCN/LFMO/IL/CPE was successfully used to determine PNZS in various drug formulations such as tablets and vials. Finally, simultaneous determination of PNZS and acetaminophen was accomplished with no interference based on the proposed sensor.

Preparation and study of characteristics of LiCoO2/Fe3O4/Li2B2O4 nanocomposites as ideal active materials for electrochemical hydrogen storage

The nanocomposites of LiCoO2/Fe3O4/Li2B2O4 were designed by the Pechini route using different fuels for the optimization of their morphology and structure. Compared to other fuels, citric acid can act as both an ideal fuel and a capping agent. The ratio of the EG : H2O mixture is another parameter, which was studied in terms of its effects on the structural characterization. The optimized sample with a rod shape was selected to compare with the bulk sample through electrochemical hydrogen storage capacity. The discharge capacity for rod-shaped nanocomposites measured was 1284 mA h g-1. However, the discharge capacity for the bulk morphology was calculated to be about 694 mA h g-1. The magnetic, electrochemical and structural analyses were performed to investigate the properties of LiCoO2/Fe3O4/Li2B2O4 nanocomposites.