Synthesis, structure and properties of the layered CuxTiS2 compounds

• Published in: Journal of alloys and compounds Vol. 750; pp. 42 - 54
• Main Authors: Titov, A.A., Shkvarina, E.G., Merentsov, A.I., Doroshek, A.A., Shkvarin, A.S., Zhukov, Yu.M., Rybkin, A.G., Pryanichnikov, S.V., Uporov, S.A., Titov, A.N.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 25-06-2018
• Subjects: Crystal structure; Electronic structure; Intercalated compounds; Layered phase; Physical properties; Titanium dichalcogenides; Electronic structure; Physical properties; Layered phase; Titanium dichalcogenides; Intercalated compounds; Crystal structure
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2018.03.376

A low-temperature layered phase CuxTiS2 (0 ≤ x ≤ 0.7) has been prepared. The occupation of both octahedral and tetrahedral sites by the copper atoms in the interlayer gap of the TiS2 lattice is revealed. The presence of two concentration regions of 0 ≤ x ≤ 0.3 and 0.5 ≤ x ≤ 0.7, which differ in the concentration dependence of the unit cell volume, has been observed. In the first region the unit cell volume increases with x, in the second region it decreases. This difference may be associated with the competition between Cu-Ti and Cu-S covalent centres. The electrical and magnetic properties of the materials are in a good agreement with this assumption. The electronic structure of CuxTiS2 in the low copper concentrations region has been studied using X-ray photoelectron, resonant photoelectron and absorption spectroscopy techniques. It was found that, in the low copper concentrations region, the charge transfer from Cu to the conduction band of TiS2 along with the formation of covalent centres is observed.
•Low-temperature layered phase CuxTiS2 in wide concentration range were synthesized.•Crystal structure was refinement.•The electrical and magnetic properties of the materials were measured.•Occupation by Cu of the tetrahedral sites in the van der Waals gap was observed.•Formation of a chemical bond due to the hybridization of Cu/S states can be assumed.