• Harraz, Farid A.
• Ahmed, Jahir
• Rahman, M. Hafizur
• Jalalah, Mohammed
• Nayem, N. I.

Abstract

<jats:p>In the present work, we developed a cheap and sensitive H<jats:sub>2</jats:sub>O<jats:sub>2</jats:sub> electrochemical sensor. Herein we fabricated an electrochemical sensor electrode using a naturally extracted hematite ore decorated with conducting polythiophene (Pth) and gold nanoparticles (AuNPs). A simple synthesis route was adopted for the electrocatalyst synthesis, where Pth was synthesized through oxidative polymerization and then combined with Hematite Ore nanostructure via a simple ultrasonication process. Later a simple photo-reduction approach was used to develop a 1%Au@5%Pth/Hematite Ore nanocomposite. The as-fabricated Au@Pth/Hematite Ore nanocomposite was successfully characterized by applying X-ray diffraction (XRD), X-ray Photoelectron Spectroscopy (XPS), High-Resolution Transmission Electron Microscope (HR-TEM), and Field Emission Scanning Electron Microscope (FE-SEM) techniques. The obtained results reveal that undoped naturally extracted hematite ore is composed of Fe<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub> and Fe<jats:sub>3</jats:sub>O<jats:sub>4</jats:sub> phases. The catalytic efficiency of the newly designed nanocomposite and its sensing ability towards H<jats:sub>2</jats:sub>O<jats:sub>2</jats:sub> were assessed using electrochemical techniques including electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV), linear sweep voltammetry (LSV) and highly sensitive amperometric (i-t) techniques. The Au@Pth/Hematite Ore/GCE sensor showed a wide linear dynamic range of 0.50–9.50 mM with high sensitivity of 69.18 <jats:italic>μ</jats:italic>AmM<jats:sup>−1</jats:sup>cm<jats:sup>−2</jats:sup>. The limit of detection (LOD) was estimated to be 5.18 <jats:italic>μ</jats:italic>M. The examined sensor demonstrated acceptable reproducibility, repeatability as well as stability. The sensor electrode also showed anti-interference behavior in the presence of different inorganic and organic interfering ions or molecules during the H<jats:sub>2</jats:sub>O<jats:sub>2</jats:sub> determination. Moreover, the proposed sensor exhibits acceptable recovery of H<jats:sub>2</jats:sub>O<jats:sub>2</jats:sub> in real sample analysis. Hence, this novel sensor is regarded as a promising contender in scientific and industrial domains.</jats:p><jats:p><jats:inline-formula><jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="jesad2644-ga.jpg" xlink:type="simple" /></jats:inline-formula></jats:p>

Topics

• nanoparticle
• nanocomposite
• phase
• x-ray diffraction
• x-ray photoelectron spectroscopy
• gold
• transmission electron microscopy
• electrochemical-induced impedance spectroscopy
• cyclic voltammetry
• field-emission scanning electron microscopy
• ultrasonication