α-MoO₃ nanostructure on carbon cloth substrate for dopamine detection

Abstract

Orthorhombic molybdenum oxide (α-MoO 3 ) nanostructures were deposited on the surface of carbon cloth (CC) as a flexible and high conductive scaffold by reactive RF magnetron sputtering technique. Structure and morphology of the as prepared molybdenum coated carbon cloth (MoO 3 CC) were thoroughly characterized with field emission scanning electron microscopy, x-ray diffraction, energy dispersive x-ray and Raman spectroscopy. Benefiting from high surface area and superior conductivity of CC as well as electrocatalytic activity of α-MoO 3 nanostructures, an electrochemical sensor was fabricated. The electrochemical behavior of this new sensor toward determination of dopamine was studied in detail by cyclic voltammetry, amperometry (AM) and square wave voltammetry (SWV). Results reported here reveal that using SWV not only enhances the sensitivity of sensors to dopamine by more than 14 times compared to AM, but also offers higher linear dynamic range (1-700 μM compared to 5-550 μM). Limit of detection, for signal to noise ratio 3, was calculated to be 0.48 μM. Applicability of the proposed sensor for measurement of dopamine in real samples, like urine and pharmaceutical formulation, was also evaluated that concluded to satisfactory results.

Fabrication of a Novel Electrochemical Sensor Based on Carbon Cloth Matrix Functionalized with MoO3 and 2D-MoS2 Layers for Riboflavin Determination

“…The main advantage of using the CC was its capability to favor the electron transfer between the electrode surface and the analyte. These enhanced electroanalytical properties were demonstrated in the sensing of dopamine [9].…”

“…The surface contamination on the target material was removed by pre-sputtering the target at 0.01 mbar pressure for 10 min. The RF power was set to 150W, the distance between target and substrate was maintained at 50 mm [9]. 2D-MoS2 nanosheets were prepared by liquid phase exfoliation (LPE) in sodium cholate (SC) watery solutions (1.5 mg/mL) [6].…”

“…In a previous paper [9], we also investigated the electrochemical properties of MoO3, a semiconductor oxide with a band gap of 3.2eV which presents three crystalline structures among of which the orthorhombic (α-MoO3) phase is the most thermodynamically stable. In order to increase its poor conductivity and to improve the electrochemical characteristics, a layer of α-MoO3 was grown on flexible conductive carbon cloth (CC).…”

“…In order to increase its poor conductivity and to improve the electrochemical characteristics, a layer of α-MoO3 was grown on flexible conductive carbon cloth (CC). It was demonstrated that the high electron mobility and the large surface area provided by the carbon fibers increased the capacities of the sensor in terms of peak current and sensitivity compared to bare screen-printed carbon electrode (SPCE) [9]. The main advantage of using the CC was its capability to favor the electron transfer between the electrode surface and the analyte.…”

Mo-Based Layered Nanostructures for the Electrochemical Sensing of Biomolecules

“…DA is also crucial for memory processes and motor skills, and is known to be implied in stress-related health problems, similarly to cortisol [ 75 ]. Various layered Mo materials-modified electrodes have been proposed for this purpose [ 76 , 77 , 78 , 79 , 80 , 81 , 82 ]. Zang et al [ 83 ] synthesized, via a novel hydrothermal route, a few layer S-MoSe 2 /NSG with many rich-edge sites.…”