Total reflection X-ray fluorescence analysis using polycapillaries. A comparison with conventional setups

HECTOR JORGE SANCHEZ; ROBERTO PÉREZ; MARÍA LUISA CARVALHO; M. RUBIO

NUCLEAR INSTRUMENTS AND METHODS IN PHYSICS RESEARCH B - BEAM INTERACTIONS WITH MATERIALS AND ATOMS

ELSEVIER SCIENCE BV

Año: 2010 vol. 268 p. 3478 - 3481

0168-583X

The possibility of producing parallel X-ray beams with low divergence by means of half monolithic polycapillariesgives the impression to be useful in total reflection X-ray fluorescence (TXRF) experiments. Onone hand, the use of polycapillaries facilitates the alignment and the setup of the experiment. Asexpected, the spectra registered in the experiment shown low background and good signal–noise ratio.On the other hand, the intensity of photons on the samples when polycapillaries are employed is lowerthan in other configurations, which produces a loss of efficiency for the excitation of the sample mainlyfor light elements. In this work, different TXRF experiments were carried out and the minimum detectionlimits attained were compared with the ones obtained from TXRF using polycapillaries. The results indicatethat the decrease of intensity produced by polycapillaries is imposing when detection limits are analyzed.Nevertheless, detection limits are better than conventional XRF. The possibility of employing nonsymmetricalpolycapillaries could eventually improve the detection limits so as to be equivalent to theconventional TXRF setups.