Portable X-Ray Fluorescence (XRF) instruments have come a long way since their debut to the commercial market in the 1950s. Thankfully, the once bulky, heavy and radioactive box is now a relatively light, handheld device with results that are comparable to those acquired in a laboratory. These instruments are now being extensively applied to a wide variety of industries, including mining, agriculture, art, environment and pharmaceuticals. But how did we get here…
1895 – X-rays were accidentally discovered by Wilhelm Roentgen. Roentgen went on to win the Nobel Prize in Physics in 1901 for the discovery of X-rays.
1913 – Henry Moseley was the first to use X-rays for analysis. The instrument he built was a primitive version of what we use today, an X-ray tube that bombards a sample with high-energy electrons.
1928 – R. Glocker and H. Schreiber were the first scientists to quantitatively analyse material using the technique. Yet it took until the 1940s for the detector technology to catch up so that the technique could be applied in a practical setting.
1948 – The first commercially available X-ray spectrometer for elemental analysis was produced. This improvement in detector was key to the development of the pXRF spectrometer.
1967 – The first commercial field portable XRF became available.
1982 – The first ‘handheld’ XRF was produced. The probe weighed over 31 kg with a measurement head connected to a trolley where the electronics displayed the data.
1994 – The first one-piece fully-handheld detector was created, with real-time digital signal processing and silicon PIN diode detector. The instrument weighed 7 kg and the lightest element measurable was titanium.
2001 – The advances in X-ray tube technology allowed for the replacement of radioisotope excitation with X-ray tubes. This is because X-ray tubes have many advantages, such as improved safety, faster analysis times, and lower detection limits. The XRF spectrometer weighed 2-3 kg and the lightest element measurable was magnesium.
2008 – The SiPin detector was replaced by a silicon drift detector improving the spectral resolution of the instrument.
Today – The instruments weigh less than 2 kg and are now able to detect fluorine (with helium atmosphere) and measure sodium to uranium.
Modern XRF instruments have the capacity to analyse a variety of materials for major and trace (ppm) elements, both in-situ and in real-time. The main advances to date have been the quality and speed of data collection as well as the accuracy and precision of the collected data.
Portable XRF is now a core instrument used for metal identification, mining and mineral exploration and agricultural practises. However, the possibilities are endless with the technology entering more industries today than ever before due to their expanding application in areas such as arts and conservation, forensics, food safety, oil and gas, archaeology, manufacturing, maritime transport, aeronautics flight hardware and environmental monitoring.
The question now is, what will the future hold…?
1913: Henry Mosely used self-built equipment to prove every element’s identity is uniquely determined by the protons.
1967: Non-dispersive scintillation detector with X-ray filters.
1982: Hanford Nuclear Reserve ‘Handheld XRF’ for U
1994: NITON xl-309 – One piece and Si Pin detector
2001: Tracer II Unit- 1st X-ray tube with Ag anode from Keymaster (now Bruker)
Now: S1 Bruker Titan