X-RAY-ABSORPTION FINE-STRUCTURE STUDY OF THE ATOMIC AND ELECTRONIC-STRUCTURE OF MOLYBDENUM-DISULFIDE INTERCALATION COMPOUNDS WITH TRANSITION-METALS

The local structures of 'host' and 'guest' layers of MoS2 intercalated with M(OH)(2) (M = Mn, Co, and Ni) prepared via interaction of single -layer MoS2 dispersions and solutions of M2+ salts were studied by X-r ay absorption spectroscopy. According to M K-edge extended X-ray absor ption fine structure (EXAFS) and X-ray absorption near-edge structure (XANES) results, the electronic structure and atomic environment of th e M atoms in the intercalates are similar to that of the crystalline h ydroxides M(OH)(2). In the Ni intercalate, Mo K-edge EXAFS revealed a structural change of the 'host' MoS2 layers similar to that reported f or water dispersions of MoS2 single layers. S K-edge XANES data indica te that the change is associated with increased electron density on th e S atoms in the matrix. SO42- and Mon+ (4 < n < 6) were detected in t he intercalated materials exposed to air, suggesting that transition m etal intercalation may increase the susceptibility of the MoS2 layers to oxidation. (C) 1998 Elsevier Science S.A. All rights reserved.