Improvements in energy dispersive X-ray fluorescence detection limits with thin specimens deposited on thin transparent adhesive tape supports

The elemental detection limits observed in total reflection X-ray fluorescence analysis (TXRF) are better compared to that of energy dispersive X-ray fluorescence (EDXRF) by approximately three orders of magnitude (in pg level) mainly due to efficient excitation geometry and special features of total reflection of X-rays. Also, the matrix effects are negligible and the thin film approximation is valid for all types of specimens. The detection limits in EDXRF can be improved using thin specimens deposited on thin sample supports so that scattering and thereby background are reduced. In the present study, the detection limits in EDXRF could be improved to ng-pg level for different elements using thin specimens of the samples deposited on thin transparent adhesive tape supports. The EDXRF analytical results were in very good agreement with those of TXRF. The EDXRF detection limit achieved using this approach for Cr was found to be 1050 pg compared to 320 pg obtained in TXRF. For Y these values were found to be 320 and 168 pg respectively. The EDXRF detection limits achieved in the present work have given a new EDXRF analysis methodology for sample analysis with detection limits comparable to TXRF using a simple instrumentation. (C) 2014 Elsevier B.V. All rights reserved.