Comprehensive analysis of the effect of Na doping concentration on the essential physical properties of K2PdO2: A first principle study

Abstract

This study investigates the effects of sodium (Na) doping on K₂PdO₂, a semiconductor with a wide band gap and low absorption of visible electromagnetic radiation, using Wien2k based on Density Functional Theory (DFT). The results reveal that Na doping is an effective approach to enhancing the optical absorption properties of these materials. Both the pure and doped compounds exhibit negative formation energies, confirming their thermodynamic and structural stability. Density of States and electronic band structure analyses show that all compounds remain semiconducting, with the band gap decreasing from 2.29eV to 1.65eV upon doping. Increased charge due to doping induces polarization and reduces light velocity, as reflected by the rise in the refractive index with higher Na content. Additionally, optical conductivity improves, indicating enhanced sensitivity to visible light. These findings, along with the favorable thermoelectric response, position K₂PdO₂ as a promising candidate for various thermoelectric device applications.