JEOL has created an exceptional new type of wavelength-dispersive spectrometer (WDS) that uses a variable space grating to capture very low energy rays (so-called “soft” X-Rays) efficiently and in parallel.
These new Soft X-Ray Emission Spectrometers (SXES) have a high spectral resolution (0.3 eV), allowing the Nitrogen Kα and Titanium Lℓ lines to be resolved with only 1.78 eV separation, as well as with ultra-low energy, low-concentration sensitivity, allowing them to detect Li even at low single-digit weight percent concentrations.
Another, and perhaps most important feature is its capacity to do chemical state analysis.
When electrons produce X-Rays, the spectrometer identifies variations between the conduction band and valence band electrons, allowing bonding and crystal structure in samples containing the same elements. For instance, differentiating highly organized pyrolytic graphite from diamond and amorphous C, which are all made entirely of carbon.
A new version of the Soft X-Ray Emission Spectrometer with a wider energy range has been added by JEOL (SXES-ER). The spectral range of the SXES-ER is 100 eV to ~2300 eV. Using the L, M, and N lines, users cannot only collect light elements but also transition metals and heavy elements.
The SXES is available for both JEOL FE-SEMs and JEOL W/LaB6/FEG EPMA systems.
Li Detection: Peak Shape in Compounds
A single K-line is detected in metallic Li. Depending on the occupancy of the valence band, an extra satellite peak can form in Li-compounds.
High Energy Resolution Spectral Mapping
For the first time, the SXES permits direct observation of the Li-K emission. It can also map the multiple chemical states that emerge from varying degrees of battery charge within a Li battery.
It is possible to map two separate Li-K emission lines. The lower energy Li-K line’s intensity correlates to the battery’s degree of charge, while the higher energy Li-K line’s intensity corresponds to the quantity of metallically linked Li.
Fast Parallel Detection
The SXES can concurrently capture a spectrum over a wide energy range thanks to a newly built aberration corrected grating system and a highly sensitivity X-Ray CCD.
Chemical State Analysis
Chemical state analysis using the SXES is equivalent to that of XPS or EELS. The Fermi-edge of the Al-L emission of Al metal was used to demonstrate that the SXES had an energy resolution of 0.3 eV.
Key Features
SXES
- Extreme spectral resolution 0.3 eV Al-L fermi edge
- No moving parts, which results in high stability and reproducibility
- Part of an integrated analytical system or as a stand-alone detector
- Easy to use spectral mapping
- Outstanding light element detection (suitable for Li)
- Perfect for chemical state analysis of light elements – essential for battery research
- Superb sensitivity - a few 10 s of ppm B in steel
- Energy range 50 eV – 210 eV (even 2nd and 3rd order lines have a high P/B ratio and high resolution)
SXES-ER
- Ultrahigh spectral resolution (Zr-M z 1.2 eV FWHM JS300N / Fe-L α 5.0 eV FWHM JS200N)
- No moving parts, which results in high stability and reproducibility
- Part of an integrated analytical system or as a stand-alone detector
- Easy to use spectral mapping
- Outstanding light element detection (B-S 1st order)
- Allows detection of first order K lines (N-S), L lines (Ca – Mo), and M Lines (Cd – Bi)
- Trace element – chemical state analysis of Be-N