Analytical & Bioanalytical Electrochemistry
Volume:15 Issue: 12, Dec 2023

An innovative investigation was conducted to characterize a Zinc Oxide-modified nano carbon (NC-ZnO) electrode for the development of an initial model for detecting Endocrine-Disrupting Chemicals (EDCs). NC-ZnO synthesis was carried out by the hydrothermal method and characterized. The particle size of the carbon-modified ZnO is determined to be 22.85 nm. The electrochemical performance evaluation demonstrates that the ZnO modification significantly improves electron transfer and enhances the electrochemical performance of NC electrodes in terms of increased peak currents and narrower current peaks. The results of our study indicate that the NC@ZnO composite electrode is effective in detecting fipronil, with efficient electron transfer occurring at a low oxidation potential. Additionally, the electrode demonstrates a highly linear sensitivity to fipronil concentration in the range of 10 to 10-3 µg/L, and it boasts an impressive limit of detection (LoD) of 0.00393 µg/L. Moreover, the NC@ZnO composite electrode shows exceptional stability in detecting fipronil, as evidenced by the low stability coefficients of %RSDR (0.048) and %PRSDR (0.13). These findings suggest that the newly developed NC@ZnO composite electrode holds great promise as a sensitive tool for detecting fipronil in the environment, thus potentially helping to reduce its negative impacts on human health and ecosystems.

This study presents a pioneering application of a novel quantitative structure-property relationship (QSPR) model to predict the selectivity coefficients of a cation-selective electrode. Specifically, the selectivity coefficients of a Lanthanum (La(III)) membrane sensor utilizing 8-amino-N-(2-hydroxybenzylidene) naphthylamine (AIP) as the sensing ligand were efficiently estimated and predicted. To establish the QSPR model, calculated molecular descriptors were employed, considering the limitation of cation descriptors. A new strategy was introduced for descriptor calculation by optimizing the structure of Mn+-AIP and utilizing density functional theory (DFT) with the B3LYP functional and SBKJC basis set. Genetic algorithm (GA) and stepwise techniques were employed for descriptor selection, with the most significant descriptors identified. Following variable selection, multiple linear regression (MLR) was employed to construct linear QSPR models. Comparative analysis revealed that the GA-MLR modeling approach exhibited superior performance compared to the stepwise-MLR method. Furthermore, the predictions generated by the GA-MLR model demonstrated excellent agreement with the experimental values. The proposed strategy outlined in this study has the potential to be extended to other QSPR investigations involving cation-selective electrodes. These findings contribute to the advancement of predictive modeling in the field of cation-selective sensors and offer valuable insights for future research in this area.

The effect of the benzimidazole-2-ylcarbamate methyl (Carbendazim) in corrosion inhibition for carbon steel has been studied using stationary and transient electrochemical techniques. The potentiodynamic curves show that Carbendazim acts as a mixed-type inhibitor. The electrochemical impedance diagrams show a capacitive response of carbon steel with and without inhibitors at different concentrations in 1M HCl. The polarization resistance increases with increasing inhibitor concentration. Consequently, the inhibition efficiency increases and reaches 84% at 10-2M and its adsorption follows the Langmuir isotherm. This shows that the protective effect of Carbendazim is significant in an acidic medium. The study of the synergistic effect with KI shows that an equimolar mixture of KI and Carbendazim compound enhances the inhibition efficiency. The theoretical investigation of the tested compound ability to inhibit corrosion using DFT shows that the HOMO, LUMO, and electrostatic potential maps surfaces can qualitatively identify the most nucleophilic and electrophilic centers, this will enable us to give an adsorption mechanism for the inhibitor studied on the metal surface.

Ambarella is one of the most popular tropical fruits in Southeast Asia. Since it has a high concentration of organic acids, the fruit has the potential to be employed as an electrolyte in biobatteries. In this work, Zn-Cu biobattery electrolytes are derived from the flesh and peel of ambarella fruit. The Open- and Closed-Circuit Voltage, Maximum Power Density, and Battery Capacity of Zn-Cu Biobatteries were investigated. The OCV of the fruit's flesh was 455 mV, while the OCV of its peel was 530 mV. Given the average CCV created by ambarella peel was 471.3 mV and the average CCV generated by ambarella flesh was 342.1 mV.   The highest power of Zn-Cu biobatteries was 0.27 mW when fruit flesh was used as the electrolyte and 0.22 mW when fruit peel was used as the electrolyte, Indicating a difference of 18.5%. The peel of an ambarella fruit has a battery capacity of 540 mAh, while the flesh has a capacity of 328 mAh for the Zn-Cu biobattery. This indicates that Zn-Cu with an Ambarella peel has a greater capacity but less power, urging that it be investigated prior to any prospective use.

In this study, tranexamic acid (Txa) (in 0.1 M Sulfuric acid) modified glassy carbon electrode (GC) was tested, for the first time, as a sensor for determining the most consumed pain reliever, paracetamol (ACOP) by differential pulse voltammetry (DPV). The tranexamic acid-modified glassy carbon (rTxa/GC) electrode was characterized by a scanning electron microscope (SEM). Cyclic voltammetry (CV), linear sweep voltammetry (LSV), and electrochemical impedance spectroscopy (EIS) (in aqueous and nonaqueous solution) were used to evaluate the electrochemical performance of electrodes. The modified electrode increased the oxidation peak current of ACOP significantly in this case. The experimental results provide that rTxa/GC electrode displayed excellent electrocatalytic response to the oxidation ACOP. Additionally, the rTxa/GC electrode exhibited excellent electrocatalytic activity for the electrochemical determination of ACOP in Britton-Robinson (BR) buffer solution with pH values ranging from 2 to 12. As a result, the effective electroactive surface area of rTxa/GC electrode increased by using a BR buffer solution with pH 6. The linear range was 25 – 80 μM for ACOP with a limit of detection (LOD) of 4.7 μM and a limit of detection (LOQ) of 14.2 μM.

Given the rising concerns regarding climate change, there has been a noticeable rise in research dedicated to exploring materials aimed at bolstering the efficiency of energy conversion and storage systems. The development of efficient and affordable non-precious electrocatalysts for the oxygen reduction reaction (ORR) is crucial for the advancement of fuel cells and metal-air batteries. In this study, we synthesized a novel hybrid electrocatalyst for ORR consisting of Layered Double Hydroxide (LDH)-derived triple Metal Oxide (IIIMO) decorated on a porous graphitic carbon nitride (PCN); as well, its physiochemical and electrochemical performance was assessed. This composite facilitates a synergistic enhancement of catalytic activity for the ORR, benefiting from its binary composition and hierarchically porous structure. The synthesis of the PCN-IIIMOx% composite employed a straightforward layer-by-layer assembly method, integrating several weight ratios of IIIMO (where x represents 0.1, 0.2, 0.5, and 1). The physiochemical analyses confirmed the incorporation of the as-synthesized MMO on the PCN lattice. The electrochemical analyses showed that the PCN-IIIMO20% has the best performance holding the onset potential of -0.09 V, electron transfer number of 3.3 and current retention durability of 79% after 7200s of continuous operation.