DFT Approach for Improving the Electronic and Optical Properties of Kznf3 Perovskite::  Impact of Copper Doping

Noureddine Noureddine; Younes  Ziat; Hamza  Belkhanchi; Ayoub Koufi

doi:10.51646/jsesd.v14iSTR2E.798

المؤلفون

Noureddine Noureddine Engineering and Applied Physics Team (EAPT), Superior School of Technology, Sultan Moulay Slimane University, Beni Mellal, Morocco. And The Moroccan Association of Sciences and Techniques for Sustainable Development (MASTSD), Beni Mellal, Morocco.
Younes Ziat Engineering and Applied Physics Team (EAPT), Superior School of Technology, Sultan Moulay Slimane University, Beni Mellal, Morocco. And The Moroccan Association of Sciences and Techniques for Sustainable Development (MASTSD), Beni Mellal, Morocco.
Hamza Belkhanchi Engineering and Applied Physics Team (EAPT), Superior School of Technology, Sultan Moulay Slimane University, Beni Mellal, Morocco. And The Moroccan Association of Sciences and Techniques for Sustainable Development (MASTSD), Beni Mellal, Morocco.
Ayoub Koufi Engineering and Applied Physics Team (EAPT), Superior School of Technology, Sultan Moulay Slimane University, Beni Mellal, Morocco. And The Moroccan Association of Sciences and Techniques for Sustainable Development (MASTSD), Beni Mellal, Morocco.

DOI:

https://doi.org/10.51646/jsesd.v14iSTR2E.798

الملخص

This study investigates the structural, electronic and optical properties of cubic perovskite KZnF₃, in its pure state and doped with copper (Cu) at a concentration of 12.5%, using the full-potential linearized augmented plane wave (FP-LAPW) method within the framework of density functional theory (DFT) which is implemented in the Wien2k code. Density-of-state (DOS) analysis reveals that doping significantly alters electronic properties, notably through the emergence of 3d-Cu impurity states near the Fermi level, resulting in a shift towards the valence band and a decrease of the band gap to 2.72 eV. Optical properties were also analyzed through dielectric functions (real and imaginary parts), absorption coefficient, optical conductivity, refractive index and reflectivity. Cu doping enhances absorption in the visible spectrum, increases electron polarization and optimizes charge carrier mobility, boosting the material's performance in optoelectronic devices. These results highlight the key role of doping in engineering perovskite properties for advanced applications, including photovoltaic technologies, optical sensors and next-generation electronic systems.

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