The Charge Distribution, Seebeck Coefficient, and Carrier Concentration of CuCr0.99Ln0.01S2 (Ln = Dy-Lu)

Evgeniy V Korotaev; Mikhail M Syrokvashin; Irina Yu Filatova; Aleksandr V Sotnikov; Alexandr V Kalinkin

doi:10.3390/ma16062431

The Charge Distribution, Seebeck Coefficient, and Carrier Concentration of CuCr_0.99Ln_0.01S₂ (Ln = Dy-Lu)

Materials (Basel). 2023 Mar 18;16(6):2431. doi: 10.3390/ma16062431.

Authors

Evgeniy V Korotaev¹, Mikhail M Syrokvashin¹, Irina Yu Filatova¹, Aleksandr V Sotnikov¹, Alexandr V Kalinkin²

Affiliations

¹ Nikolaev Institute of Inorganic Chemistry, Siberian Branch, Russian Academy of Sciences, 630090 Novosibirsk, Russia.
² Boreskov Institute of Catalysis, Siberian Branch, Russian Academy of Sciences, 630090 Novosibirsk, Russia.

Abstract

The atom oxidation states were determined using the binding energies of the core S2p-, Cu2p-, Cr2p-, and Ln3d-levels in CuCr_0.99Ln_0.01S₂ (Ln = Dy-Lu) solid solutions. The charge distribution on the matrix elements (Cu, Cr, and S) remained unaffected after cationic substitution. The sulfur atoms were found to be in the S^2- oxidation state, the copper-Cu⁺, and the chromium-Cr³⁺. The cationic substitution of the initial CuCrS₂-matrix occurred via the isovalent mechanism. The obtained results were compared with the electrophysical properties for CuCr_0.99Ln_0.01S₂. The measured carrier concentration was from 10¹⁷ to 10¹⁸ cm^-3. The largest Seebeck coefficient value of 157 µV/K was measured for CuCr_0.99Yb_0.01S₂ at 500 K. The cationic substitution with lanthanides allowed one to enhance the Seebeck coefficient of the initial CuCrS₂-matrix.

Keywords: Hall voltage; Seebeck coefficient; XPS; lanthanides; layered copper–chromium disulfide; thermoelectricity.

Grants and funding

19-73-10073/Russian Science Foundation