X-Ray Fluoroscence Spectroscopy

Horiba XGT-5200 X-ray Analytical Microscope

The Horiba XGT-5200 X-ray analytical microscope can be used in the X-ray Fluorescence spectroscopy of various samples. X-ray fluorescence is a non-destructive analytical technique which qualitatively characterizes samples. When compared to SEM/EDX analysis which uses an electron beam which only allow surface analysis, the penetrating nature of an X-ray beam allows visualization and characterization of features that are invisible to the eye. This penetrating ability also allows higher detection limits when compared with SEM/EDX. The patented XGT (X-Ray Guide Tube) technology has merged the traditional X-ray fluorescence methodology with small spot analysis. The instrument uses two X-ray beams with diameters of 10 µm and 100 µm to offer versatile analytical capabilities. 

Principle

The principle behind this instrument is X-ray fluorescence. During this process, the sample is irradiated with high energy X-rays from a controlled X-ray tube. When an atom that is present in the sample is struck with an X-ray with energy that is greater than the atom’s K or L shell binding energy, an electron from one of the atom’s inner orbital shells is dislodged. Following this, the atom uses an electron from one of the atom’s higher energy orbital shells to fill the vacant space left in the inner orbital due to the dislodged electron in order to regain stability. When this electron drops to the lower energy level, it releases a fluorescent X-ray with an energy value that is equal to the specific difference in energy between the two quantum states of the electron. This energy is detected by the detector present in the instrument and is recorded. Based on this energy value, the specific elements in a material could be identified as these energy values differ from element to element. During analysis, XRF peaks with varying intensities are created and will be present in the spectrum. The spectrum shows a graphical representation of X-ray intensity peaks as a function of energy peaks. Based on the peak energy, the element can be identified and the height/intensity of a peak indicates the concentration of a particular element in a given sample.

Strengths

• Can detect elements between 11Na and 92U
• Non-destructive

Limitations

• Elements below 11Na and above 92U cannot be detected by this instrument. Therefore, the elemental percentages generated by the instrument are given as a percentage from the detectable elements and not the actual elemental composition
• XRF analysis also does not allow distinguishing variations among isotopes of an element, and ions of the same element in different valence states.

Applications

• XRF Spectroscopy can be used in a wide array of applications including the fields of archaeology, environmental analysis, forensic science, manufacturing of coatings, geology, materials testing, electronics, pharmaceuticals etc.
• The instrument can be used to determine the elemental composition of materials
• The instrument can be used in elemental mapping to observe the distribution of elements in a given sample

Technical Specfications

• Detection range : Sodium (Na11) to Uranium (U92)
• X-Ray Tube : 50kV, 1mA. Rh Target
• Detector : SDD (LN2 Free)
• Atmosphere : Air or Localized vacuum

X-Ray Transmission Image
     • Mapping Functions : 10mm × 100mm Area
     • Sample Chamber : 400mm × 350mm × 40mm
     • Whole Image : 5m Pixel

Phase Analysis
     • X-Ray Guide Tube 10µm +100µm
     • Transmission X-Ray Detector Nal(Tl) Scintillator
     • Sample type Solid/Liquid/Powder
     • Sample Stage: Motorized XY Stage and Z-axis by manual
     • Data Acquisition: Single/Multi point analysis