Assembly of magnetic nanoparticles at a liquid/liquid interface. Catalytic effect on ion transfer process

C.I. CÁMARA; L.M.A. MONZÓN; J.M.D. COEY; L.M. YUDI

JOURNAL OF ELECTROANALYTICAL CHEMISTRY - (Print)

ELSEVIER SCIENCE SA

Lugar: Amsterdam; Año: 2015 vol. 756 p. 77 - 83

1572-6657

The adsorption of cobalt (Co) and cobalt-boron (CoxB) magnetic nanoparticles (NPs) at a liquid/liquid interface is examined. The Co NPs have a remanence magnetization while the CoxB is completely demagnetized in the absence of an external magnetic field. Cyclic voltammetry experiments reveal that the adsorption of these NPs at the interface shifts the positive potential limit towards lower values showing that a catalytic effect on the ion transfer process is occurring, while electrochemical impedance spectroscopy demonstrates that their mode of self-assembly is directed by their magnetic properties. CoxB NPs form a homogeneous film while Co segregates in macroscopic patches, leaving some areas of the interface uncovered.