Mössbauer spectroscopy

Mössbauer spectroscopy is based on the recoilless resonant absorption and emission of g-ray by nuclei in solids. It is one of the most sensitive techniques in terms of energy resolution, capable of detecting changes in just a few parts per 1011 [1]. Mössbauer spectroscopy is unique in its sensitivity to subtle changes in the chemical environment of the nucleus including oxidation state changes, the effect of different ligands and the magnetic environment.
In the last decades, significant advances have been achieved in the field of electrochemical energy storage, especially in Li and Na-ion batteries. These advances have been possible thanks to the fundamental understanding of the electrochemical processes involved in the reaction of both positive and negative electrodes with lithium. Mössbauer spectroscopy has actively contributed to these advances since the beginning, starting only few years after its discovery; it was used for the ex situ characterization of batteries materials as well as for in situ measurements.

An entire issue of the Mössbauer Effect Reference and Data Journal, the main publication which gathers the community of Mössbauer spectroscopists, has been recently devoted to the application of this technique to the field of Li-ion batteries.[2]
The ALISTORE-ERI Mössbauer platform offers various facilities allowing measurements in transmission as well as scattering modes (5 spectrometers). Moreover, the platform is equipped to enable analyses between 4 and 800 K, allowing investigations of temperature-dependent properties. Concerning in situ analyses, several electrochemical cells are available in the platform for 57Fe and 119Sn Mössbauer experiments under operando conditions with the possibility of combining both Mössbauer and XRD analyses. The study of the lithiation/delithiation mechanism of LiFeSO4F is a typical illustration of the contribution of Mössbauer spectroscopy to batteries’ studies [3].