Binder-free carbon nanotube electrode for electrochemical removal of chromium

Haitao Wang, Chongzheng Na

Research output: Contribution to journalArticle

44 Scopus citations

Abstract

Electrochemical treatment of chromium-containing wastewater has the advantage of simultaneously reducing hexavalent chromium (CrVI) and reversibly adsorbing the trivalent product (CrIII), thereby minimizing the generation of waste for disposal and providing an opportunity for resource reuse. The application of electrochemical treatment of chromium is often limited by the available electrochemical surface area (ESA) of conventional electrodes with flat surfaces. Here, we report the preparation and evaluation of carbon nanotube (CNT) electrodes consisting of vertically aligned CNT arrays directly grown on stainless steel mesh (SSM). We show that the 3-D organization of CNT arrays increases ESA up to 13 times compared to SSM. The increase of ESA is correlated with the length of CNTs, consistent with a mechanism of roughness-induced ESA enhancement. The increase of ESA directly benefits CrVI reduction by proportionally accelerating reduction without compromising the electrode 's ability to adsorb CrIII. Our results suggest that the rational design of electrodes with hierarchical structures represents a feasible approach to improve the performance of electrochemical treatment of contaminated water. (Figure Presented).

Original languageEnglish
Pages (from-to)20309-20316
Number of pages8
JournalACS Applied Materials and Interfaces
Volume6
Issue number22
DOIs
StatePublished - Nov 26 2014

Keywords

  • Carbon nanotube array
  • Chromium electrosorption
  • Chromium reduction kinetics
  • Composite without polymer binder
  • Industrial wastewater
  • Langmuir isotherm
  • Three-dimensional electrode

Fingerprint Dive into the research topics of 'Binder-free carbon nanotube electrode for electrochemical removal of chromium'. Together they form a unique fingerprint.

  • Cite this