Electrical and antimicrobial studies of multifunctional ZrO₂ doped borate glasses and glass ceramics

In this study, borate-based glass and glass-ceramics doped with varying concentrations of ZrO₂ were synthesized, followed by controlled heat treatment for crystallization. X-ray diffraction, density, Fourier-transform infrared spectroscopy, field emission scanning electron microscope, and dielectric relaxation spectroscopy were employed to characterize the prepared samples. XRD analysis confirmed the formation of the nanocrystalline ZrO₂ phase within the glass-ceramic matrix. The average crystallite size, determined by the Scherrer formula, fell within the nanometric range. DRS investigated the dielectric response of all samples over a wide frequency range (0.1 Hz-1 MHz) at 30 °C. It showed enhanced dielectric properties with increasing ZrO₂ content. Significantly increased permittivity while decreased loss tangent for glass and glass ceramics with higher ZrO₂ content. Furthermore, glass ceramic exhibited better dielectric properties than glass samples. For electrical properties, the optimal mol% suggested for Zr⁴⁺ is 2 since it exhibited the highest permittivity (~ 23 at 1 MHz) and lowest loss tangent (~ 0.005) for glass and glass ceramics. The substitution of CaO by ZrO₂ increases both permittivity and AC conductivity while reducing the dielectric losses, confirming the enhancement of dielectric properties. Furthermore, the antimicrobial activity of the prepared samples was tested. The antimicrobial activity of the glass-ceramic results from the presence of ZrO₂ nanocrystals, which act in a similar manner to ZrO₂ nanoparticles. Cytotoxicity and long-term stability assays were carried out. The results display the effect of ZrO₂ on structure, crystallinity, and the noticed electrical and biological responses, making them promising materials for use in applications that require electrical functionality and biocompatibility.