Original Article

Structural electronic and thermoelectric properties of CuGe₂P₃ ternary compound in trigonal phase promising for electronic applications

¹ Research Unit on Emerging Materials (RUEM), University Ferhat Abbas of Setif 1, Setif 19000, Algeria
² Department of Physics, Faculty of Sciences, University of M'sila University Pole, Road Bourdj Bou Arreiridj, 28000 M'sila, Algeria
³ Department of Chemistry, Faculty of Sciences, University of M'sila University Pole, Road Bourdj Bou Arreiridj, 28000 M'sila, Algeria
⁴ Laboratory for the Study of Surfaces and Interfaces of Solid Materials (LESIMS), University Ferhat Abbas of Setif 1, Setif 19000, Algeria
⁵ Department of Physics, College of Science, Taif University, Taif 21944, Saudi Arabia
⁶ Laboratory of Optoelectronic and Compounds, Faculty of Sciences, Ferhat Abbas University of Setif 1, Setif 19000, Algeria
⁷ Faculty of Sciences and Technology, University of Mohamed El Bachir El Ibrahimi-Bordj BouArreridj, Bordj Bou-Arreridj 34000, Algeria
⁸ Research Center in Industrial Technologies CRTI, P.O. Box 64, Cheraga, 16014 Algiers, Algeria

^* e-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.

Received: 18 July 2025
Accepted: 19 September 2025
Published online: 17 October 2025

Abstract

This study examines the structural, electronic, and thermoelectric properties of trigonal-phase copper germanium phosphide (CuGe₂P₃) using density functional theory (DFT) calculations. The bulk modulus is 68.98 GPa with a pressure derivative of 4.53, obtained from the Birch–Murnaghan equation of state based on energy–volume data. This is lower than the 86.7 GPa reported for the disordered zincblende phase, indicating significant structural differences. Thermoelectric transport properties were evaluated at 100, 300, and 500 K. At 100 K, strong p-type transport with high Seebeck coefficients was observed, highlighting pronounced low-temperature electronic sensitivity. Using a representative lattice thermal conductivity, the estimated figure of merit zT reaches ∼0.29 at 500 K, suggesting moderate thermoelectric performance. These results demonstrate that CuGe₂P₃ combines favorable structural stability with promising transport behavior, making it a potential candidate for mid-temperature thermoelectric applications.