TOTAL-REFLECTION X-RAY-FLUORESCENCE ANALYSIS OF LIGHT-ELEMENTS

Total reflection X-ray fluorescence analysis (TXRF) is an energy dispe rsive technique of special excitation geometry suitable for the determ ination of light elements, such as Al, Mg, Na and F, and even down to B. A special spectrometer adapted to the problems of the detection of low energy X-rays is required, details of which are discussed. An over view of such possible X-ray sources as standard X-ray tubes, special w indowless X-ray tubes and synchrotron radiation is given and results a re presented. Various methods of changing the spectral distribution fo r efficient excitation and for the reduction of background are discuss ed. Detection limits depend upon the source, and are in the range of s ome hundred femtograms using synchrotron radiation and in the range of some pg using a special windowless X-ray tube with a Si anode. (C) 19 97 Elsevier Science B.V.