Issue 14, 2014

Bio-inspired surface-functionalization of graphene oxide for the adsorption of organic dyes and heavy metal ions with a superhigh capacity

Abstract

By utilizing the synergistic effect of poly-dopamine (PD) with functional groups and graphene oxide (GO) with a high surface area, a series of sub-nano thick PD layer coated GO (PD/GO) composites were fabricated by a well-controlled self-polymerization of dopamine via catechol chemistry and used for effectively decontaminating wastewater. The obtained PD/GO could selectively adsorb the dyes containing an Eschenmoser structure and showed an extremely high adsorption capacity up to 2.1 g g−1, which represents the highest value among dye adsorptions reported so far. The adsorption mechanism was investigated by FTIR analysis, solution pH effect, and some control experiments. It was concluded that the adsorption process was based on the Eschenmoser salt assisted 1,4-Michael addition reaction between the ortho position of the catechol phenolic hydroxyl group of PD and Eschenmoser groups in the dyes. The adsorption isotherms were explored according to the Langmuir and Freundlich models respectively, and matched well with the Langmuir model. The thermodynamic parameters (ΔH, ΔG, ΔS, and E) were also calculated, which suggested an exothermic and spontaneous adsorption process. In addition, PD/GO exhibited an improved adsorption capacity for heavy metal ions (53.6 mg g−1 for Pb2+, 24.4 mg g−1 for Cu2+, 33.3 mg g−1 for Cd2+, and 15.2 mg g−1 for Hg2+, respectively) than pure PD and GO. Our results indicate the effectiveness of the synergistic effect of individual components on designing new functional composites with high performance.

Graphical abstract: Bio-inspired surface-functionalization of graphene oxide for the adsorption of organic dyes and heavy metal ions with a superhigh capacity

Article information

Article type
Paper
Submitted
18 Nov 2013
Accepted
20 Jan 2014
First published
20 Jan 2014

J. Mater. Chem. A, 2014,2, 5034-5040

Author version available

Bio-inspired surface-functionalization of graphene oxide for the adsorption of organic dyes and heavy metal ions with a superhigh capacity

Z. Dong, D. Wang, X. Liu, X. Pei, L. Chen and J. Jin, J. Mater. Chem. A, 2014, 2, 5034 DOI: 10.1039/C3TA14751G

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements