Activated carbon-based supercapacitor electrodes synthesized from biomass or waste-derived biomass have recently attracted considerable attention because of their low cost, natural abundance, and power delivery performance. In this work, purple-corncob-based active carbons are prepared by KOH activation and subsequently evaluated as a composite electrode for supercapacitors using either an acidic or an alkali solution as the electrolyte. The synthesis of the material involves mixing the purple corncob powder with different concentrations of KOH (in the range of 5% to 30%) and a thermal treatment at 700 °C under an inert atmosphere.
View Article and Find Full Text PDFThis study reports the development of a new electrochemical sensor based on a carbon paste electrode (CPE) composed of biomass-based orange peel activated carbon (ACOP) and multiwalled carbon nanotubes (MWCNTs), and this composite is used for the electrochemical detection of cadmium ions (Cd). The ACOP/MWCNT composite was characterized by FTIR, Raman, and electrochemical impedance spectroscopy. The electrochemical evaluation of Cd was performed using square wave and cyclic voltammetry.
View Article and Find Full Text PDFNifedipine, a widely utilized medication, plays a crucial role in managing blood pressure in humans. Due to its global prevalence and extensive usage, close monitoring is necessary to address this widespread concern effectively. Therefore, the development of an electrochemical sensor based on a glassy carbon electrode modified with carbon nanofibers and gold nanoparticles in a Nafion film was performed, resulting in an active electrode surface for oxidation of the nifedipine molecule.
View Article and Find Full Text PDFPtPd bimetallic catalysts supported on hierarchical porous carbon (HPC) with different porous sizes were developed for the oxygen reduction reaction (ORR) toward fuel cell applications. The HPC pore size was controlled by using SiO nanoparticles as a template with different sizes, 287, 371, and 425 nm, to obtain three HPC materials denoted as HPC-1, HPC-2, and HPC-3, respectively. PtPd/HPC catalysts were characterized by scanning electron microscopy, X-ray photoelectron spectroscopy, X-ray diffraction, and high-resolution transmission electron microscopy.
View Article and Find Full Text PDFThis paper reports the development of a voltammetric sensor using glassy carbon electrode based on hierarchical porous carbon (HPC) with silver sulfide nanoparticles (AgSNP), Nafion and fullerene (C) for the determination of nitrite in foods. Raman spectroscopy, scanning electron microscopy, transmission electron microscopy and energy-dispersive X-ray were used to characterize the morphology and composition of the materials. The use of HPC and C in the construction of the electrode contributed toward the enlargement of the specific surface area and the improvement of the electrochemical performance of the device.
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