# Multiwalled Carbon Nanotubes (MWCNT) / Poly O-Cresophthalein Complexone Film (POCF) Modified Electrode for Determination of Cd (II) Using Anodic Stripping Voltammetry

J Jayadevimanoranjitham, C Lakshmi Devi, S Sriman Narayanan

► To cite this version:

J Jayadevimanoranjitham, C Lakshmi Devi, S Sriman Narayanan. Multiwalled Carbon Nanotubes (MWCNT) / Poly O-Cresophthalein Complexone Film (POCF) Modified Electrode for Determination of Cd (II) Using Anodic Stripping Voltammetry. Mechanics, Materials Science & Engineering MMSE Journal. Open Access, 2017, 9, 10.2412/mmse.97.37.377. [https://hal.science/hal-01504699](https://hal.science/hal-01504699)

HAL Id: hal-01504699

https://hal.science/hal-01504699

Submitted on 10 Apr 2017

HAL is a multi-disciplinary open access
archive for the deposit and dissemination of sci-
entific research documents, whether they are pub-
lished or not. The documents may come from
teaching and research institutions in France or
abroad, or from public or private research centers.

L'archive ouverte pluridisciplinaire HAL, est
destinée au dépôt et à la diffusion de documents
scientifiques de niveau recherche, publiés ou non,
émanant des établissements d'enseignement et de
recherche français ou étrangers, des laboratoires
publics ou privés.

<figure><img src="image_1.png" /></figure>

Distributed under a Creative Commons Attribution 4.0 International License
# Multiwalled Carbon Nanotubes (MWCNT) / Poly O-Cresophthalein Complexone Film (POCF) Modified Electrode for Determination of Cd (II) Using Anodic Stripping Voltammetry

J. Jayadevimanoranjitham<fnref n="1" />, C. Lakshmi Devi<fnref n="1" />, S. Sriman Narayanan<fnref n="1" />,ᵃ

<figure><img src="image_2.png" /></figure>

DOI 10.2412/mmse.97.37.377 provided by [Seo4U.link](https://link.springer.com/10.2412/mmse.97.37.377)

**Keywords:** Multiwalled carbon nanotube, cadmium, POCF, stripping voltammetry.

**ABSTRACT.** This work describes about the anodic stripping voltammetric determination of trace amount of cadmium ions using Multiwalled Carbon Nanotube / Poly O-Cresophthalein Complexone Film (MWCNT/POCF) modified electrode. The proposed modified electrode was prepared by electropolymerization of O-Cresophthalein Complexone over the MWCNT on Paraffin Impregnated Graphite Electrode (PIGE). The surface morphology of MWCNT/POCF modified electrode was characterized by Scanning Electron Microscope (SEM) and Square Wave Voltammetry (SWV). A linear range of 18µg/L to 332µg/L with a detection limit of 6.2µg/L was obtained for the determination of Cd (II) using MWCNT/POCF modified electrode. The modified electrode was found to be environment friendly mercury free electrode for sensitive of determination of Cd (II).

**Introduction.** Heavy metals are highly toxic environmental pollutant which causes major effects to the human health even at lower concentration. Even though some of heavy metals used for various biological functions in human beings but they became toxic when they exceed certain threshold limits. Cadmium is one of the toxic heavy metal that enters the water bodies and is a major pollutant through various industrial and agricultural sectors [1]. Cadmium mainly targets the kidney but causes some health effects to other organs such as lung, liver. Cadmium stored in the kidney for longer period, mainly affects the proximal tubular cells of kidney which results in renal dysfunction. Due to prolonged exposure of air born cadmium human beings are affected by lung cancer [2]. Bones are degenerated to cadmium intake. So it is very important to develop simple and highly sensitive analytical methods for assessing environmental pollutants in soil, water, and air to improve the quality of environment and human life. Numbers of analytical techniques have been used to quantify the amount of Cd (II). Anodic stripping voltammetry using modified electrode is a prominent analytical tool for determination of heavy metal ions because when comparing with other analytical techniques stripping voltammetry posses some of advantages such as insuit monitoring, less time consuming for sample preparation, high sensitivity and excellent reproducibility [3-5].

Basically electrochemical sensing of heavy metal ion using stripping voltammetry involves the usage of hanging mercury drop electrode [HMDE] and mercury film electrode [MFE] as working electrode, but due to the toxicity of mercury and difficulty in disposal of mercury electrodes, alternative methods without using mercury electrode have been developed using number of modifiers [6-8]. Here in we have developed mercury free electrode for the determination of Cd (II) using multiwalled carbon nanotube and O-Cresophthalein Complexone as working electrode. Carbon nanotubes (CNTs) are recently used in stripping analysis because they have strong sorption properties, high mechanical

<footnote n="1">1 – Department of Analytical Chemistry, School of Chemical sciences, University of Madras, Guindy Campus, Chennai – 600 025, Tamil Nadu, India</footnote>

<footnote>a – sriman55@gmail.com</footnote>
strength, high conductivity and high surface area [9]. O-Cresophthalein Complexone is a metal ion indicator and used for determination of metal ions [10]. Due to wide application of CNTs and metal chelating nature of O-Cresophthalein Complexone an attempt has been made to develop MWCNT/POCF modified electrode for the determination of Cd (II).

**Experiment.** The modified electrode was prepared by mechanically immobilizing MWCNT over the polished end of PIGE followed by electropolymerization of O-Cresophthalein Complexone over the surface of PIGE/MWCNT electrode by dipping this electrode in 0.1M PBS pH 6 solution containing 0.1mM O-Cresophthalein Complexone dissolved in 0.1M NaOH. The resulted PIGE/MWCT-POCF electrode was used for determination of Cd (II). The determination of Cd (II) involves preconcentration of metal ions towards the electrode surface by dipping the PIGE/MWCT-POCF electrode in 0.1M ABS (pH 5) solution containing Cd (II) and then solution was stirred which has resulted in the complex formation of Cd (II) with POCF via four -COO- group. Then this electrode was transferred to the fresh electrolyte 0.1M ABS (pH 5) solution to reduce the all the Cd (II) to Cd (0) by applying a potential of -1.2V for 180s. The reduced metal ions were stripped by anodic stripping voltammetry using SQW from -1.2V to -0.3V in 0.1M ABS (pH 5). By measuring the peak current the quantity of Cd (II) was measured. Regeneration of electrode is achieved by dipping the electrode in 0.1M EDTA (pH 5) solution for 120 sec. Fig.1 shows the scheme for preparation of modified electrode and determination of Cd (II).

<figure><img src="image_3.png" /><figcaption>Fig. 1. Scheme for preparation of modified electrode and determination of Cd (II).</figcaption></figure>

**Results and discussion.**

The surface morphology of the modified electrode is characterized by SEM. Fig.2. Shows the SEM images of a) bare electrode b) MWCNT-POCF electrode c) MWCNT-POCF-Cd electrode d) EDX for MWCNT-POCF-Cd electrode. The SEM image of MWCNT-POCF shows the tube like structure for the presence of MWCNT and the polymer film is formed over the MWCNT. The white spherical shape in the Fig.2c show the presence of cadmium ions over the polymer film and the corresponding EDX spectrum confirms the presence of various elements in the electrode surface.
<figure><img src="image_4.png" /><figcaption>Fig. 2. SEM image of a) bare electrode, b) MWCNT-POCF electrode, c) MWCNT-POCF-Cd electrode, d) EDX for MWCNT-POCF-Cd electrode.</figcaption></figure>

**Determination of Cd (II) by anodic stripping voltammetry.** Under optimized condition the modified electrode was used for determination of Cd (II) using square wave voltammetry. Fig. 3 shows the SQW response of MWCNT-POCF modified electrode for Cd (II) over the concentration range from 18µg/L to 332µg/L in 50 ml of 0.1M ABS pH 5 at the deposition time of 180s. From the figure we can see the linear increase in the peak current upon increasing the concentration of Cd (II) with sensitivity of 0.0820µA/µg and a correlation coefficient of 0.9940 with a detection limit of 6.2µg/L.
<figure><img src="image_5.png" /><figcaption>Fig. 3. a) Square wave voltammograms of different concentration of Cd (II) in 0.1M ABS (pH 5), reduction potential of -1.2V, deposition time 180s., b) Corresponding calibration plot.</figcaption></figure>

**Summary.** A mercury free metal ion sensor using MWCNT-POCF modified electrode was successfully fabricated and used for determination of Cd (II) in aqueous solution. The electrode was prepared by electropolymerization method. Since the POCF has more number of negatively charged ions, the metal ions easily forms complex. Then the metal ions were reduced by applying potential of -1.2V for 180s, this reduced metal was stripped to metal ions using anodic stripping voltammetry. On varying the concentration of metal ion the peak current is also increased linearly with the detection limit of 6.2µg/L. Hence the proposed modified electrode successfully used for determination of Cd (II).

**Acknowledgements.** The authors gratefully acknowledge university grants commission New Delhi, India for financial assistance through Rajiv Gandhi National Fellowship.

**References**

[1] Jarup L, Akesson A Current status of cadmium as an environmental health problem, Toxicol Appl Pharmacol. 2009, Aug 1, 238(3):201-8. DOI: 10.1016/j.taap.2009.04.020

[2] Contaminants in the Food Chain on a request from the European, Commission on cadmium in food. The EFSA Journal (2009) 980, 1-139. DOI:10.2903/j.efsa.2012

[3] Sukeri Anandhakumar, Jayaraman Mathiyarasu and Kanala Lakshimi Narasimha Phani, Anodic stripping voltammetric determination of cadmium using a “mercury free” indium film electrode Analyst, 2013, 138, 5674. DOI: 10.1039/c3an01070h

[4] Saiwei Wu, Xiaolei Huang, Yuhua Wu, Liping Luo, Yuancheng Jin, Qun Li, Differential Pulse Anodic Stripping Voltammetry Detection of Cadmium with Nafion-Graphene Modified Bismuth Film Electrode Int. J. Electrochem. Sci., 10 (2015) 8255 – 8262.

[5] Bang Lin Li, Zhi Ling Wu, Chang Hong Xiong, Hong Qun Luo, Nian Bing Li, Anodic stripping voltammetric measurement of trace cadmium at tin-coated carbon paste electrode, Talanta 88 (2012) 707–710, DOI:10.1016/j.talanta.2011.11.070

[6] Deepak Singh Rajawa, Nitin Kumar and Soami Piara Satsangee Trace determination of cadmium in water using anodic stripping voltammetry at a carbon paste electrode modified with coconut shell powder, Journal of Analytical Science and Technology 2014, 5:19, DOI: 10.1186/s40543-014-0019-0.
[7] Bagheri H, Afkhami A, Shirzadmehr A, Khoshsafar H, Ghaedi H (2012) Novel potentiometric sensor for the determination of Cd2+ based on a new nano-composite. Int J Environ Anal Chem, DOI: 10.1080/03067319.2011.649741

[8] Gil Ho Hwanga, Won Kyu Hana, Joon Shik Park b, Sung Goon Kanga, Determination of trace metals by anodic stripping voltammetry using a bismuth-modified carbon nanotube electrode, Talanta 76 (2008) 301–308, DOI:10.1016/j.talanta.2008.02.039

[9] Tsai Y.C, Chen J.M, Li S.C, Marken F, Simple Cast-Deposited Multi-Walled Carbon Nanotube/NafionTM Thin Film Electrodes for Electrochemical Stripping Analysis Electrochem. Commun. 6 (2004) 917. DOI:10.1007/s00604-005-0364-1

[10] Brett Paull, Paul R. Haddad, Chelation ion chromatography of trace metal ions using metallochromic ligands, Trends in analytical chemistry, vol. 18, no. 2, 1999, DOI: [10.1016/S0165-9936(98)00104-6](https://doi.org/10.1016/S0165-9936(98)00104-6)

Cite the paper

J. Jayadevimanoranjitham, C. Lakshmi Devi, S. Sriman Narayanan (2017). *Multiwalled Carbon Nanotubes (MWCNT) / Poly O-Cresophthalein Complexone Film (POCF) Modified Electrode for Determination of Cd (II) Using Anodic Stripping Voltammetry*. *Mechanics, Materials Science & Engineering*, Vol 9. DOI: 10.2412/mmse.97.37.377