Surface-modified CuO nanoparticles for photocatalysis and highly efficient energy storage devices

Herein we report multifunctional surface-modified CuO nanomaterials were used to fulfill escalating needs in the electrochemical energy storage system and to achieve efficient photocatalysts for the degradation of AR88 organic dye. Due to the atom economy, ease of synthesis, high capacitance, observable electrochemical responsiveness, and low bandgap in CuO-based nanomaterials, its active surface was modified through cationic surfactant CTAB. Surface-modified nanoparticles were characterized using various characterization techniques such as XRD, DRS, FESEM, and TEM. Intriguingly the synthesized materials demonstrated a capacitance of 133 F/g with a long-term charge-discharge cycle of 2000 cycles. In addition, at pH 11, the material also exhibited a superior dye degradation performance under the UV lamp by showing 94.8% AR88 degradation at a catalyst concentration of 1.0 g/L. Hence, we believe this concept would provide novel insights into the preparation of the simplest and cheaper multifunctional materials for next-generation energy storage and photocatalytic applications.

A Short Review Comparing Carbon-Based Electrochemical Platforms With Other Materials For Biosensing SARS-Cov-2

Due to the 2019 SARS-CoV-2 outbreak, low-cost, fast, and user-friendly diagnostic kits for biosensing SARS-CoV-2 in real samples employing multiple working electrodes are in high demand. Choosing SARS-CoV-2 detecting electrodes is difficult because each has advantages and limitations. Carbon-based electrochemical sensing applications have attracted attention from the electrochemical sensing community because carbon and carbon-based materials have been a godsend for testing utilizing an electrochemical platform. Carbon working electrode electrochemical platforms are cost-effective and fast. Covid-sensors use carbon-based materials because they can be easily changed (with inorganic and organic functionalities), have quick response kinetics, and are chemically resistant. Covid-19 sensing materials include graphene and graphite. This review explains how carbon materials have been employed in N and S protein electrochemical detection. Here, we discussed a carbon-based technology for SARS-CoV-2 biosensing. We've compared carbon-based electrochemical sensing to different electrodes.

A Fukui Analysis of an Arginine-Modified Carbon Surface for the Electrochemical Sensing of Dopamine

Amino acid-modified carbon interfaces have huge applications in developing electrochemical sensing applications. Earlier reports suggested that the amine group of amino acids acted as an oxidation center at the amino acid-modified electrode interface. It was interesting to locate the oxidation centers of amino acids in the presence of guanidine. In the present work, we modeled the arginine-modified carbon interface and utilized frontier molecular orbitals and analytical Fukui functions based on the first principle study computations to analyze arginine-modified CPE (AMCPE) at a molecular level. The frontier molecular orbital and analytical Fukui results suggest that the guanidine (oxidation) and carboxylic acid (reduction) groups of arginine act as additional electron transfer sites on the AMCPE surface. To support the theoretical observations, we prepared the arginine-modified CPE (AMCPE) for the cyclic voltammetric sensing of dopamine (DA). The AMCPE showed excellent performance in detecting DA in blood serum samples.

Pre-post electron transfer regioselectivity at glycine modified graphene electrode interface for voltammetric sensing applications

In the last few years, glycine (GL) showed good experimental evidence as an electron transfer (ET) mediator at the carbon (in particular graphene (GR)) interface. However, ET properties of GL modified GR interface are still not known completely. These can be achieved using density functional theory-based models. Modelling of modified carbon electrode interfaces is essential in electroanalytical chemistry to get insights into their electronic and redox properties. Here we have modelled glycine modified graphene interface to find out its interfacial redox ET properties. Conceptual density functional theory concepts like frontier molecular orbital (FMO) theory and analytical Fukui functions were utilized to predict the ET sites on the modified graphene surface. It is shown that at the glycine-modified graphene interface, amine groups act as additional oxidation sites and carboxylic acid groups as additional reduction sites. Therefore, glycine acts as an ET mediator at the graphene-based electrode interface. The obtained results are well supported by previously published experimental reports.

Studies of Monoamine Neurotransmitters at Nanomolar Levels Using Carbon Material Electrodes: A Review

Neurotransmitters (NTs) with hydroxyl groups can now be identified electrochemically, utilizing a variety of electrodes and voltammetric techniques. In particular, in monoamine, the position of the hydroxyl groups might alter the sensing properties of a certain neurotransmitter. Numerous research studies using electrodes modified on their surfaces to better detect specific neurotransmitters when other interfering factors are present are reviewed to improve the precision of these measures. An investigation of the monoamine neurotransmitters at nanoscale using electrochemical methods is the primary goal of this review article. It will be used to determine which sort of electrode is ideal for this purpose. The use of carbon materials, such as graphite carbon fiber, carbon fiber micro-electrodes, glassy carbon, and 3D printed electrodes are only some of the electrodes with surface modifications that can be utilized for this purpose. Electrochemical methods for real-time detection and quantification of monoamine neurotransmitters in real samples at the nanomolar level are summarized in this paper.

Theoretical and electrochemical analysis of L-serine modified graphite paste electrode for dopamine sensing applications in real samples

In this study, we used the grinding modification approach to modify the carbon paste electrode (CPE) from an environmentally friendly catalyst (L-serine). L-serine(L-s) is shown to be an effective electrocatalytic at the modified CPE (MCPE) interface for detecting dopamine (DA). L-sMCPE showed excellent activity to detect DA in commercial injection samples with a recovery range of 98.9 to 100.5%. Theoretical studies were used to understand the electrocatalysis of L-serine at the atomic level using frontier molecular orbitals and analytical Fukui assay. The amine group of L-serine works as an extra oxidation site (cause for enhanced reduction peak DA) and a carboxylic acid group (reason for enhanced oxidation peak DA) at the L-sMCPE interface, according to our theoretical findings. Improvements to these processes might have a big influence on knowledge of the electrode interface for sensing applications.

Fabrications of electrochemical sensors based on carbon paste electrode for vitamin detection in real samples

This review article examines some advancements in electrochemical sensors for vitamin detection in the past few decades. Vitamins are micronutrients found in natural foods essential for maintaining good health. Most vitamins cannot be synthesized by a body and must be obtained externally from natural food. Vitamins make a class of organic chemicals that shortage can cause various ailments and diseases, and consumption can become harmful if it exceeds the usually needed level. Because of these factors, vitamin detection has become highly significant and sparked interest over the past few decades. The electrochemical sensors function on the concept of electro­chemical activity of practically all vitamins. This implies that concentrations of vitamins in the electrolyte may be detected by measuring the amounts of current generated at certain potentials by their oxidation and reduction at the working electrode surface. Voltammetric methods are superior to other methods because they are cheaper and show sharp sensitivity with faster analysis speed. The carbon-based electrodes, in particular carbon paste electrodes (CPE), have significant advantages like easier catalyst incorpo­ration, surface renewability, and expanded potential windows with lower ohmic resistance. This review goes into detail about several electro­chemical sensors involving CPE as the working electrode and its utilization to detect water- and fat-soluble vitamins.

Plant seed extract assisted, eco-synthesized C-ZnO nanoparticles: Characterization, Chromium (VI) ion adsorption and kinetic studies

This report attempts to elucidate the potential of plant seed extract assisted synthesis of Graphite based zinc oxide nanoparticles (C-ZnO NPs) towards removal of chromium (VI) ions from the water samples. The Graphene-zinc oxide composites were characterised using TGA, XRD, FTIR and SEM. The C-ZnO nanocomposites have found to remove chromium from the sample through adsorption process. The sensitivity of chromium removal through adsorption is found to be in the range of 40-240 mg. The adsorption behaviour was found to be fitting with Langmuir isotherm model and the adsorption reaction follows pseudo second order kinetics.

Selective detection of Cu2+ ions using a mercaptobenzothiazole disulphide modified carbon paste electrode and bismuth as adjuvant: a theoretical and electrochemical study

Bismuth adsorbed on the MBTS-modified surface facilitates the mass and charge transfer necessary for copper's selective sensing.

Analytic Alchemical Derivatives for the Analysis of Differential Acidity Assisted by the h Function

Analytical calculation of alchemical derivatives based on auxiliary density perturbation theory is described, coded, and validated. For the case where the nucleus is a hydrogen atom and the nuclear charge is changed from 1 to 0, it turns out that a good estimate of the proton binding energies can be obtained very efficiently. First-order results correspond exactly to the molecular electrostatic potential evaluated at the hydrogen nucleus location (removing self-repulsion), in agreement with previously reported extensive studies. Therefore, the second-order results reported here are refinements in accuracy that finally allow a quantitative exploration of differential acidity. Furthermore, the recently reported h function is produced in its analytical form as a byproduct and local descriptor associated with the proton binding energy values found with this approach. In an example application, proton binding energies are computed for a family of imidazolium derivatives to demonstrate the capabilities and the stability of the method with respect to changes in basis set or exchange-correlation functional.

Quantum chemical and electrochemical studies of lysine modified carbon paste electrode surfaces for sensing dopamine

We have improved the sensitivity of a carbon paste electrode from lysine for the sensitive detection of dopamine.

Regioselectivity in hexagonal boron nitride co-doped graphene

The active electron transfer (ET) sites on the graphene surface can be controlled by hexagonal boron nitride (h-BN) doping.