The behavior of the intercalant AlCl${}_4$ anion during the formation of graphite intercalation compound. An X-ray absorption fine structure study

This work aims to study the insertion of AlCl${}_4^{-}$ anion in the crystalline structure of oriented pyrolytic graphite (PG) at the point of view of the anion itself. The electronic and atomic structures of the anion at different intercalation stages are studied. In particular double-edge (bicolor) X-ray absorption spectroscopy at the Al and Cl K-edges is carried out, highlighting a contraction of the anion bonding at the highest intercalation degree obtained electrochemically (stage 3), while the electronic population changes for both the edges upon cycle. (© 2024 The Authors. physica status solidi (a) applications and materials science published by Wiley‐VCH GmbH)