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The synthesis of cheap and efficient materials for developing fuel cells is challenging for researchers. In this study, nickel sulfide nanoparticles (NiS NPs) and nickel sulfide/molybdenum disulfide (NiS/MoS2) nanocomposite modified ITO electrodes were synthesized based on a simple and facile hydrothermal method. Raman spectroscopy, X-ray diffraction, SEM, FTIR, and energy dispersive X-ray spectroscopy analysis were used to study the morphologies, structures, and phase identification of the electrocatalysts. The electrocatalytic activities of the modified electrodes towards the methanol oxidation reaction were also evaluated based on the cyclic voltammetry technique. The results indicated that NiS/MoS2 exhibited higher electrocatalytic activity towards the methanol electrooxidation in alkaline media that could be attributed to the uses of MoS2 with high surface area, which facilitates the diffusion of methanol molecules. Thus, the NiS/MoS2 is a good candidate for application in the direct methanol fuel cell.

Paracetamol (PC) is one of the most common non-steroidal anti-inflammatories, pain-killer, and antipyretic drugs. Thus, the development of a cheap, access, and accurate analytical technique is necessary for monitoring the purity of the PC in their pharmaceutical formulations. Herein, a layer of polypyrrole (PPy) was used to modify gold nanoflowers/gold electrodes and then applied to determine PC in the presence of 4-aminophenol. The relationship between the PC concentrations (within a range from 100 nmol L − 1 to 25 µmol L − 1) and their corresponding current peaks demonstrated a linear curve with a limit of detection (LOD) as low as 133 nmol L − 1. The synthesized PPy/Au nanoflowers nanocomposite modified Au electrode was successfully used to monitor the purity of the Novadol tablets. Then the electrochemical results were validated by the gas chromatography technique. Hence, the developed electrode displays a significant PC-sensing capability even at trace concentrations, maintaining functionality for reuse without substantial deterioration in its original performance.

This review incorporates a large number of chromatographic systems modified by the surfactants. A large number of solvent systems and stationary phases are summarized in this paper. Three different kinds of surfactants (anionic, cationic, and nonionic) are used as modifiers for stationary phases as well as solvent systems. Surfactants are used at all the three different concentration levels (below, above, and at critical micelle concentration) where surfactants behave differently. Modifications of both stationary phases and solvent systems by surfactants produced a new generation of chromatographic systems. Microemulsion solvent systems are also incorporated in this paper. Microemulsion thin-layer chromatography is a new approach in the field of chromatography.

In this paper, we are reporting the influence of addition of aromatic acids (anthranilic and benzoic acid) and their sodium salts on the micellar morphological changes in three cationic gemini surfactant solutions, viz. 5 mM tetramethylene-1,4-bis(N-hexadecyl-N,N-dimethylammonium bromide), 10 mM pentamethylene-1,5-bis(N-hexadecyl-N,N-dimethylammonium bromide), and 10 mM hexamethylene-1,6-bis(N,-hexadecyl-N,N-dimethylammonium bromide). The solubilization site of the counterions (obtained from the additives) near the micellar surface are inferred by 1H NMR. The behavior is explained in the light of binding of counterions to the micelle as well as the nature of the functional group attached to the additive. [ABSTRACT FROM AUTHOR]