Journal Article

Sensitive Electrochemical Detection of 4-Nitrophenol with PEDOT:PSS Modified Pt NPs-Embedded PPy-CB@ZnO Nanocomposites

Jalalah, Mohammed, Alam, Md. Mahmud, Rahman, Mohammed M., Faisal, Mohd, Ahmed, Jahir, Alruwais, Raja Saad, Asiri, Abdullah M., Harraz, Farid A.

2022

Overview

In this study, a selective 4-nitrophenol (4-NP) sensor was developed onto a glassy carbon electrode (GCE) as an electron-sensing substrate, which decorated with sol–gel, prepared Pt nanoparticles- (NPs) embedded polypyrole-carbon black (PPy-CB)/ZnO nanocomposites (NCs) using differential pulse voltammetry. Characterizations of the NCs were performed using Field Emission Scanning Electron Microscopy (FESEM), Energy-Dispersive Spectroscopy (EDS), X-ray Photoelectron Spectroscopy (XPS), Ultraviolet–visible Spectroscopy (UV–vis), Fourier Transform Infrared Spectroscopy (FTIR), High Resolution Transmission Electron Microscopy (HRTEM), and X-ray Diffraction Analysis (XRD). The GCE modified by conducting coating binders [poly(3,4-ethylenedioxythiophene) polystyrene sulfonate; PEDOT:PSS] based on Pt NPs/PPy-CB/ZnO NCs functioned as the working electrode and showed selectivity toward 4-NP in a phosphate buffer medium at pH 7.0. Our analysis of 4-NP showed the linearity from 1.5 to 40.5 µM, which was identified as the linear detection range (LDR). A current versus concentration plot was formed and showed a regression co-efficient R2 of 0.9917, which can be expressed by ip(µA) = 0.2493C(µM) + 15.694. The 4-NP sensor sensitivity was calculated using the slope of the LDR, considering the surface area of the GCE (0.0316 cm2). The sensitivity was calculated as 7.8892 µA µM−1 cm−2. The LOD (limit of detection) of the 4-NP was calculated as 1.25 ± 0.06 µM, which was calculated from 3xSD/σ (SD: Standard deviation of blank response; σ: Slope of the calibration curve). Limit of quantification (LOQ) is also calculated as 3.79 µM from LOQ = 10xLOD/3.3. Sensor parameters such as reproducibility, response time, and analyzing stability were outstanding. Therefore, this novel approach can be broadly used to safely fabricate selective 4-NP sensors based on nanoparticle-decorated nanocomposite materials in environmental measurement.

• Publisher: MDPI AG,MDPI
• Subject: 4-nitrophenol detection / Binders / Biosensors / Black carbon / Buffers / Calibration / Carbon / Carbon black / Chromatography / Decoration / differential pulse voltammetry / Dispersion / Electrochemical analysis / Electrochemistry / Electrodes / Emission spectroscopy / Emissions / environmental safety / Ethanol / Fourier transforms / Glassy carbon / glassy carbon electrode / Health aspects / High resolution / Infrared spectroscopy / Linearity / Mathematical analysis / Metal oxides / Methods / Morphology / Nanocomposites / Nanoparticles / Nanotechnology / p-Nitrophenol / pH effects / Photoelectron spectroscopy / Photoelectrons / Polymers / Polystyrene / Properties / Pt-NPs-embedded PPy-CB/ZnO nanocomposites / Reproducibility / Response time / Scanning electron microscopy / Selectivity / Sensitivity / Sensors / Standard deviation / Substrates / Sulfonates / Surface area / Transmission electron microscopy / Ultraviolet spectroscopy / Voltammetry / X ray photoelectron spectroscopy / X-ray diffraction / Zinc oxide