Hydrogen evolution reaction at PdNPs decorated 1:1 clay minerals and application to the electrocatalytic determination of p -nitrophenol

Application of palladium nanoparticles supported organo-kaolinite for 4-chloro-2-nitroaniline catalytic reduction and electrochemical detection

Palladium nanoparticles (PdNPs) supported organo-kaolinite was used as a solid catalyst for the reduction and electrochemical detection of 4-chloro-2-nitroaniline (CNA). During the catalytic reduction in presence of NaBH4, the effects...

Novel construction of carbon nanofiber/CuCrO2 composite for selective determination of 4-nitrophenol in environmental samples and for supercapacitor application

A simple hydrothermal process has been used to prepare a carbon nanofiber/copper chromium dioxide (CNF/CuCrO₂) composite for the selective detection of 4-nitrophenol (4-NP) and supercapacitor applications. The electrochemical sensor was developed with a glassy carbon electrode (GCE) modified with the CNF/CuCrO₂ composite by the drop-casting method. The structural formation of the prepared materials was confirmed by infrared spectroscopy, electrochemical impedance spectroscopy, Raman spectroscopy, scanning electron microscopy, X-ray diffraction, and transmission electron microscopy. To investigate the electrochemical efficiency of the electrode, various electroanalytical techniques, namely, differential pulse voltammetry (DPV), cyclic voltammetry (CV) and galvanostatic charge–discharge tests, were employed. The GCE/CNF/CuCrO₂ modified electrode exhibited excellent electrocatalytic behavior for the detection of 4-NP under optimized conditions with a low detection limit (0.022 μM), long linear response range of 0.1–150 μM, and high sensitivity (20.02 μA μM⁻¹ cm⁻²). The modified electrode was used for the detection of 4-NP in real samples with satisfactory results. In addition, the GCE/CNF/CuCrO₂ electrode has advantages such as stability, reproducibility, repeatability, reliability, low cost, and practical application. The CNF/CuCrO₂ composite coated Ni-foam electrodes also exhibited excellent supercapacitor efficiency, with a high specific capacitance of up to 159 F g⁻¹ at a current density of 5 A g⁻¹ and outstanding cycling stability. Hence, the CNF/CuCrO₂ composite is a suitable material for 4-NP sensors and energy storage applications.

A simple hydrothermal process has been used to prepare a carbon nanofiber/copper chromium dioxide (CNF/CuCrO₂) composite for the selective detection of 4-nitrophenol (4-NP) and supercapacitor applications.

Electrochemical determination of 4-nitrophenol in environmental water samples using porous graphitic carbon nitride-coated screen-printed electrode

We demonstrate a facile preparation of novel oxidized graphitic carbon nitride (O-gC₃N₄) applied as an efficient electrocatalyst for highly sensitive electrochemical detection of 4-nitrophenol (4-NP) in environmental water samples. As-prepared O-gC₃N₄ were characterized by attenuated total reflection infrared spectroscopy, X-ray photoelectron spectroscopy, and X-ray diffraction methods for the confirmation of different functional groups and structural phase of O-gC₃N₄. The surface morphology of the O-gC₃N₄ was characterized using field emission scanning electron microscopy and high-resolution transmission electron microscopy. Results revealed that the synthesized gC₃N₄ possessed acid functional groups, nanosheet with porous in nature. The O-gC₃N₄ was drop cast on the screen-printed electrode (SPE), and it was applied for electrochemical determination of 4-NP using cyclic voltammetry and differential pulse voltammetry (DPV) techniques. The O-gC₃N₄/SPE exhibited excellent electrocatalytic activity towards 4-NP detection. Under the optimized experimental conditions, the DPV response of O-gC₃N₄/SPE showed good linear range from 0.0033 to 0.313 μM with a detection limit (S/N = 3) of 0.075 μM. The developed electrode has successfully applied for the determination of 4-NP in different environmental water samples, and the results have shown satisfied.