Technology

The combination of innovative ideas with most modern X-ray technology results in a new generation of a very compact, portable TXRF spectrometer:

• a specially designed, very compact and air-cooled micro focus X-ray tube in metal-ceramics technology
• a modern multi-layer X-ray optics for beam focussing and monochromatization
• a Peltier-cooled, high resolution XFlash^® X-ray detector (SDD) of the latest generation.

As a result, this TXRF-spectrometer is totally independent of liquid nitrogen and cooling water! The maximum power consumption is only 180 W, which makes it especially interesting for mobile applications.

The S2 PICOFOX working principle is based on the method of total reflection X-ray fluorescence (TXRF) analysis. An air-cooled X-ray tube typically with molybdenum target generates an X-ray beam, which is reduced to a narrow energy range by a multi-layer monochromator. The fine beam impinges on a polished sample carrier at a very small angle (< 0.1°) and is totally reflected. The characteristic fluorescence of the sample is emitted and measured in an energy-dispersive X-ray detector. Due to the short distance to the carrier, the fluorescence yield is very high and the absorption by air is very low.

The main difference between TXRF and conventional XRF spectrometers is the use of monochromatic radiation and total reflection optics. Illuminating the sample with a totally reflected beam reduces absorption and scattering of the beam in the sample matrix. Resulting benefits include a significantly enhanced fluorescence yield, largely reduced background noise, and consequently much higher sensitivities to elements present even in trace amounts.

In addition, the preparation of the sample substance as a thin layer avoids matrix effects. Therefore quantitative analysis can easily be performed using an internal standard.