Density functional quantum screening of the structural, electronic, phonon, and thermophysical properties of Cu-based chalcogenides for interface thermal performance and energy applications

Researchers are actively prioritizing the development of ecologically friendly and energy-efficient materials for renewable energy devices, such as thermoelectric generators, to tackle the upcoming energy concerns. We have performed an extensive examination of the structural, phonon, electronic, thermoelectric, and thermodynamic properties of Cu-based chalcogenides TMCu₃S₄ (TM = V/Nb/Ta) for their prospective application in renewable energy technologies. The use of the GGA method within the framework of density functional theory (DFT) enables a thorough examination of exchange and correlation energy potentials using first-principles computations. Based on the computed structural parameters, it is evident that TaCu₃S₄ is the most stable compound among TMCu₃S₄ (TM = V/Nb/Ta) due to its lowest ground state energy. TB-mBJ produced improved energy bandgaps of VCu₃S₄, NbCu₃S₄, and TaCu₃S₄ are 0.575, 0.725, and 0.824 eV, respectively. The figure of merit (ZT) values for VCu₃S₄, NbCu₃S₄, and TaCu₃S₄ are 0.997, 0.946, and 0.943, respectively, at 50 K for constant chemical potential. These values render them exceedingly suitable for utilization in thermoelectric (TE) devices. The thermoelectric properties of Cu-based chalcogenides TMCu₃S₄ (TM = V/Nb/Ta) indicate that these materials have great promise for energy-related applications. The thermodynamic analysis reveals that the TMCu₃S₄ (TM = V/Nb/Ta) chalcogenide materials are thermally stabile.