Exploring the Influence of Milling Time on the Structural, Elastic, Dielectric, Morphological, and Optical Properties of CuSe Nanoparticles Produced by Mechanical Alloying

In this study, copper selenide (CuSe) nanoparticles were synthesized using high‐energy ball milling with systematically varied milling times to explore their effect on the structural, dielectric, magnetic, and optical properties of the material. X‐ray diffraction confirmed single‐phase hexagonal CuSe with decreasing crystallite size and increasing microstrain as milling progressed. Raman and electron spin resonance analyses show phonon confinement and defect‐induced magnetic suppression. Field emission scanning electron microscopy and transmission electron microscope revealed nanoscale agglomerates, while dielectric studies demonstrated size‐dependent permittivity and loss characteristics consistent with Maxwell–Wagner polarization. Optical analysis revealed a bandgap widening from 1.66 to 1.86 eV and a PL peak at 710 nm, confirming quantum confinement effects. Energy‐dispersive X‐ray spectroscopy (EDS) confirmed the purity and stoichiometry of the samples. Findings of the study establish clear structure–property relationships driven by milling‐induced microstructural evolution, demonstrating the tunability of CuSe nanoparticles for dielectric and optoelectronic applications.