Nano-Cu Modified Cu and Nano-Cu Modified Graphite Electrodes for Chemical Oxygen Demand Sensors

Abstract

Nano-Cu modified Cu (nano-Cu/Cu) and nano-Cu modified graphite (nano-Cu/C) electrodes were prepared by depositing a thin layer of copper nanoparticles on a Cu wire or graphite electrode. Chronoamperometric and cyclic voltammetry techniques were applied to deposit the nanoparticles. The effects of Cu 2+ concentration, deposition time, number of scan cycles, and scan rate were studied to determine the optimum conditions of the experiment. The applications of both electrodes in the COD analysis were performed using glucose and glycine as the models. The voltammetry of a mixture solution of glucose (mg/L) and glycine (mg/L) in 0.075 M NaOH solution showed an oxidation peak at +0.68 V vs. Ag/AgCl. Good stability of this peak current was shown with relative standard deviations lower than 3% for 10 measurements. Amperometric determination of COD at this potential showed excellent linearities at both nano-Cu/Cu and nano-Cu/C electrodes (R 2 = 0.997) as well as good precision and accuracy with estimated detection limits of around ∼9 mgO/L for both the developed electrodes. Validation using the conventional COD measurements showed that the measurements achieved the average values of 92.58 and 87.86%, respectively, for nano-Cu/Cu and nano-Cu/C electrodes. Furthermore, comparison with the theoretical COD value achieved 94.90 and 89.87%, respectively, for nano-Cu/Cu and nano-Cu/C electrodes. The results indicated that both electrodes are suitable for practical application in COD determination.

Determination of chemical oxygen demand in mixed organic solution by Ti/TiO2 nanotube array electrode method

“…in the comparison table show that our research has conducted a more comprehensive and complete study on COD determination using the prepared Ti/TiO 2 electrode, especially for the detection of single-component and multi-component solutions. Although Zhang et al and Diksy et al mentioned multi-component solutions in their work, they did not conduct in-depth research and discussion on different types and ratios of organic solutions (Zhang et al 2009;Diksy et al 2020). However, this part of the research is of great significance for an actual measurement.…”

“…In this work, a secondary anodic oxidation method was used to convert Ti electrodes into Ti/ TiO 2 nanotube array electrodes with a high-efficiency contact area and multiple active sites. The preparation method is simple and easy to achieve in a short time, without any complex procedures and expensive instruments, compared to the detection method of photoelectrocatalysis (Li et al 2006a(Li et al , 2006b(Li et al , 2007Zhang et al 2009), the instruments for preparation (Li et al 2006a(Li et al , 2006b(Li et al , 2007Zhang et al 2009;Ma et al 2011;Mo et al 2015;Kabir et al 2019;Diksy et al 2020), and the preparation time (Li et al 2006a(Li et al , 2006b(Li et al , 2007Zhang et al 2009;Ma et al 2011;Mo et al 2015;Abdel-Salam et al 2018;Carchi et al 2019;Diksy et al 2020). The effect of the types and ratios of the organics on COD measurement by the Ti/TiO 2 electrode method was studied and discussed in the range of 5-150 mg/L COD.…”

A Review on Carbon‐based Electrodes for Electrochemical Sensor of Quinolone Antibiotics

“…Analysis techniques that have been widely used usually utilize optical methods such as chemiluminescence, colorimetry, and fluorescence as well as conventional methods such as using high‐performance liquid chromatography (HPLC) and enzyme‐linked immunosorbent assay (ELISA)⋅ [12–16] . Among those methods, electrochemistry is one of the most well‐known methods for a cheap and non‐time consuming sensor application [17–20] . Accordingly, electrode material selection as a counter or working electrode is one of the important things to be considered in electrochemistry.…”

“…[12][13][14][15][16] Among those methods, electrochemistry is one of the most well-known methods for a cheap and non-time consuming sensor application. [17][18][19][20] Accordingly, electrode material selection as a counter or working electrode is one of the important things to be considered in electrochemistry. Working potential window, interaction between working electrode and modifier, medium, or electrochemical substrate, as well as stability and selectivity, are among the criteria that are usually considered in determining the appropriate electrode for an experiment.…”

Electrochemical Sensor of Levofloxacin on Boron-Doped Diamond Electrode Decorated by Nickel Nanoparticles

“…Many types of research on the detection of LEV have been reported by using various electrodes such as carbon nanotubes [11], nickel oxide porous films [12], modified screen-printed electrode (SPE) [13], and modified glassy carbon electrode (GCE) [14]. Among those electrodes, boron-doped diamond (BDD) electrode is famous for its excellent properties for sensor applications such as detecting arsenic (III) [15], neuraminidase [16], chemical oxygen demand (COD) [17], glucose [18], and many more applications such as for CO 2 reduction [19][20] and synthesis application [21]. This wide range of BDD sensor applications is known due to its low background current that supports the analysis in a very low concentration, wide potential window in aqueous solution, and high physical and chemical stability suitable for real applications [22][23].…”