Determination of Cesium on Nickel Hexacyanoferrate‐Aluminum Oxide Modified Electrodes

Abstract

This report investigates the electrochemical behavior of hexacyanoferrate casted on Ni-Al 2 O 3 modified electrodes and the preconcentration and detection of cesium ions on such films. It also studies the morphology and the composition of these surfaces. The film was grown on a glassy carbon (GC) surface. Five consecutive voltammetric cycles applied within 0.0 V and À 1.6 V at a scan rate of 10 mV/s were enough to cast the film. Scanning electron microscopy (SEM) analyses showed a homogeneous, porous but broken surface of the film. Its composition was studied by X-ray diffraction (XRD). The presence of NiHCFe was confirmed by Fourier transformed infrared spectroscopy (FT-IR). The Cs þ preconcentration from diluted solutions was accomplished in 90 s, under a negative potential of À 0.20 V applied to the modified working electrode. The detection of cesium has a good sensitivity and a wide linear interval (10 À8 and 10 À12 mol L À1). Even so, the limit of detection calculated was extremely low (2 Â 10 À16 mol L À1), cesium concentrations lower than 10 À12 mol L À1 gave signals with no analytical significance. However, to our knowledge, this is the lowest level of cesium ever detected by an electroanalytical technique.

Electrochemical Sensors

“…Delgado and co-workers described the fabrication of a nickel hexacyanoferrate-aluminum oxide-modified glassy carbon electrode capable of quantifying cesium (Cs) (94). Nickel hexacyanoferrate readily adsorbs Cs + and was utilized to preconcentrate Cs + ions at the electrode surface.…”

Proton-exchange mechanism of specific Cs+ adsorption via lattice defect sites of Prussian blue filled with coordination and crystallization water molecules

“…[30][31][32][33][34][35][36][37][38] Many papers have been written concerning Cs + extraction using PB and PBAs. [39][40][41][42][43][44][45][46][47][48][49][50][51][52] Their ability to electrochemically remove Cs + ions from radioactive waste water has also been investigated using spin-coated films of PBA NPs, Cu 3 [Fe(CN) 6 ] 2 . 27 It has been commonly accepted that the exclusive abilities of PB and PBAs to adsorb hydrated Cs + ions are caused by regular lattice spaces surrounded by cyanido-bridged metals (Fig.…”