Facile preparation of NiCo2O4@rGO composites for the removal of uranium ions from aqueous solutions

Xiumei Song; Lichao Tan; Xiaojun Sun; Huiyuan Ma; Lin Zhu; Xiaoqing Yi; Qiang Dong; Junyu Gao

doi:10.1039/c6dt03261c

Facile preparation of NiCo₂O₄@rGO composites for the removal of uranium ions from aqueous solutions

Dalton Trans. 2016 Nov 14;45(42):16931-16937. doi: 10.1039/c6dt03261c. Epub 2016 Sep 30.

Authors

Xiumei Song¹, Lichao Tan, Xiaojun Sun, Huiyuan Ma, Lin Zhu, Xiaoqing Yi, Qiang Dong, Junyu Gao

Affiliation

¹ Key Laboratory of Green Chemical Engineering and Technology of College of Heilongjiang Province, College of Chemical and Environmental Engineering, Harbin University of Science and Technology, Harbin 150040, China. tanlcking@163.com.

PMID: 27711880
DOI: 10.1039/c6dt03261c

Abstract

A hierarchical structure of NiCo₂O₄@rGO composite has been fabricated, with its structure and morphology well characterized by XRD, TEM, XPS and BET. The results proved that the NiCo₂O₄ nanosheets grow uniformly on both sides of the graphene sheets. In batch adsorption experiments, the effects of equilibrium time, pH and temperature on uranium(vi) adsorption were investigated. The main results show that the NiCo₂O₄@rGO composite has a higher affinity towards the uptake of uranium(vi) from aqueous solutions. The highest adsorption capacity reached 342.4 mg U g^-1 at pH 5.0. Kinetic analysis shows that the adsorption process is described best by a pseudo-second-order kinetic model. The uranium(vi) sorption equilibrium data correlates well with the Langmuir sorption isotherm model in the thermodynamic analysis. Thus, NiCo₂O₄@rGO composite is an excellent adsorbent for removing uranium(vi) ions.