Skip to main content
Log in

Effects of pH on electrocatalytic activity of functionalized carbon nanotubes

  • Original Contribution
  • Published:
Colloid and Polymer Science Aims and scope Submit manuscript

Abstract

In this study, we modified carbon nanotubes (CNTs) by grafting with poly(ethylene glycol) (PEG) using the “grafting to” method. The PEG-grafted CNT (CNT-g-PEG) was cast on indium tin oxide (ITO) electrode to investigate the electrocatalytic activity of CNT to the redox reactions of the Fe(CN) 3−/4−6 as a probe using cyclic voltammetry and electrochemical impedance spectroscopy. The electrocatalytic activity of CNT was correlated with CNT dispersion in the cast film on ITO as a function of pH of aqueous solution from which the film was cast. The CNT dispersions in aqueous solutions of different pH and in the cast films were examined by visual observation and zeta potential, scanning electron microscopy and transmission electron microscopy, respectively. At a pH in the range of 3–11 at which ITO electrode was modified, two functionalized CNT (fCNT and CNT-g-PEG) were both found to electrocatalyze the redox reactions of the Fe(CN) 3−/4−6 probe and the PEG grafts in CNT-g-PEG could help CNT adhere to the electrode to obtain durable modified electrode. The more uniform CNT dispersions in aqueous solutions and in the cast films appeared to have greater electrocatalytic acitivity.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7
Fig. 8
Fig. 9
Fig. 10

Similar content being viewed by others

References

  1. Shieh YT, Liu GL, Wu HH, Lee CC (2007) Effects of polarity and pH on the solubility of acid-treated carbon nanotubes in different media. Carbon 45:1880–1890

    Article  CAS  Google Scholar 

  2. Chattopadhyay J, Cortez FJ, Chakraborty S, Slater NKH, Billups WE (2000) Synthesis of water-soluble PEGylated single-walled carbon nanotubes. Chem Mater 18:5864–5868

    Article  Google Scholar 

  3. Kalinina I, Worsley K, Lugo C, Mandal S, Bekyarova E, Haddon RC (2011) Synthesis, dispersion, and viscosity of poly(ethylene glycol)-functionalized water-soluble single-walled carbon nanotubes. Chem Mater 23:1246–1253

    Article  CAS  Google Scholar 

  4. Jia F, Shan C, Li F, Niu L (2008) Carbon nanotube/gold nanoparticles/polyethylenimine-functionalized ionic liquid thin film composites for glucose biosensing. Biosens Bioelectron 24:945–950

    Article  CAS  Google Scholar 

  5. Chicharro M, Arribas AS, Moreno M, Bermejo E, Zapardiel A (2007) Comparative study of multi walled carbon nanotubes-based electrodes in micellar media and their application to micellar electrokinetic capillary chromatography. Talanta 74:376–386

    Article  CAS  Google Scholar 

  6. Rubianes MD, Rivas GA (2007) Dispersion of multi-wall carbon nanotubes in polyethylenimine: a new alternative for preparing electrochemical sensors. Electrochem Commun 9:480–484

    Article  CAS  Google Scholar 

  7. Wen Y, Wu H, Chen S, Lu Y, Shen H, Jia N (2009) Direct electrochemistry and electrocatalysis of hemoglobin immobilized in poly(ethylene glycol) grafted multi-walled carbon nanotubes. Electrochimica Acta 54:7078–7084

    Article  CAS  Google Scholar 

  8. Yang ST, Wang H, Meziani MJ, Liu Y, Wang X, Sun YP (2009) Biodefunctionalization of functionalized single-walled carbon nanotubes in mice. Biomacromolecules 10:2009–2012

    Article  CAS  Google Scholar 

  9. Jung DH, Ko YK, Jung HT (2004) Aggregation behavior of chemically attached poly(ethylene glycol) to single-walled carbon nanotubes (SWNTs) ropes. Materials Sci Eng C 24:117–121

    Article  Google Scholar 

  10. Niu L, Luo Y, Li Z (2007) A highly selective chemical gas sensor based on functionalization of multi-walled carbon nanotubes with poly(ethylene glycol). Sensors Actuators B: 361–367.

  11. Zhao W, Song C, Pehrsson PE (2002) Water-soluble and optically pH-sensitive single-walled carbon nanotubes. J Am Chem Soc 124:12418–12419

    Article  CAS  Google Scholar 

  12. Liu A, Watanabe T, Honma I, Wang J, Zhou H (2006) Effect of solution pH and ionic strength on the stability of poly(acrylic acid)-encapsulated multiwalled carbon nanotubes aqueous dispersion and its application for NADH sensor. Biosens Bioelectron 22:694–699

    Article  CAS  Google Scholar 

  13. Liang R, Peng H, Qiu J (2008) Fabrication, characterization, and application of potentiometric immunosensor based on biocompatible and controllable three-dimensional porous chitosan membranes. J Colloid Interface Sci 320:125–131

    Article  CAS  Google Scholar 

Download references

Acknowledgments

We thank National Science Council of Taiwan for financial support for this work under the contract NSC 98-2221-E-390-002-MY3.

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Yeong-Tarng Shieh.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Shieh, YT., Yu, TY., Wang, TL. et al. Effects of pH on electrocatalytic activity of functionalized carbon nanotubes. Colloid Polym Sci 290, 1–9 (2012). https://doi.org/10.1007/s00396-011-2516-7

Download citation

  • Received:

  • Revised:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s00396-011-2516-7

Keywords

Navigation