Determination of parts per billion levels of electrodeposited metals by energy dispersive x-ray fluorescence spectrometry

Abstract

Aqueous solutions of nickel(II), copper(II), and zinc(I1) are quantitatively determined to the low part per billion level by energy dispersive x-ray fluorescence (XRF) spectrometry using selective potentiostatic electrodeposition as a preconcentration technique. Novel, cylindrical monochromators between the sample and detector of the XRF system reduce background levels due to scattering from the reflective electrode surface, and yield greatly improved signal-to-noise ratios. Linear callbration curves were obtained. Minimum detection limits are less than 20 ng for the metals studied.

Graphite Optics—Current Opportunities, Properties and Limits

“…From the very beginning, there were attempts to design graphite optics on the base of flat and singly bent graphite monochromators [25]. Similarly to ideal crystals, the thin plates of HOPG were slightly bent and glued on a substrate; however the devices did not have significant efficiency in spite of the highest brightness of graphite monochromator.…”

X-ray spectrometry

“…Techniques for trace analysis have changed little in the past two years although some development of electrodeposition methods has taken place (63)(64)(65). Coprecipitation is still a favored method (66-68) with in one case (68) a silver membrane filter being used to enhance the radiation from the precipitated element.…”

X-ray spectrometry

“…Instrumental Techniques. An interesting piece of work, which falls partly in the sample preparation but rather more into the technique category, is that by Boslett et al (125). The preconcentration of Ni, Cu, and Zn ions from solution is carried out by potentiostatic electrodeposition on to the flat end of a pyrolytic graphite rod which is used directly as the sample.…”