Ho3+-Induced ZnO: Structural, Electron Density Distribution and Antibacterial Activity for Biomedical Application

Abstract

The current investigation focused on the synthesis and characterization of Zn_1-xHo_xO (X = 0, 0.02, 0.04, 0.06, and 0.08) materials. The rare-earth Ho³⁺-doped ZnO materials have been prepared using a chemical precipitation process. The phase pure hexagonal structured ZnO crystal system has been observed by powder X-ray diffraction (XRD) characterization. The detailed structural analysis of prepared materials has been investigated by the Rietveld refinement method. The surface morphology and elemental composition of the prepared materials have been characterized using scanning electron microscopy (SEM) and energy-dispersive spectroscopy (EDAX). The presence of vibrational links associated with various functional groups has been displayed by FTIR spectroscopy. The energy gap of synthesized materials has been studied using UV-Vis spectroscopy. To study the luminescence activity of produced materials, photoluminescence (PL) analysis has been utilized. The light-green emission at around 507 nm has been obtained by synthesized materials under 380-nm excitation. In addition, the electron density distribution has been accomplished in synthesized materials. At 6% of Ho³⁺, substituted ZnO exposes the maximum covalent and ionic nature between Zn-O bond along with horizontal and vertical axis, respectively. Moreover, the antibacterial activity of synthesized materials has been done through Proteus vulgaris and Enterococcus faecalis. Following that the destruction of human red blood cells has been examined by hemolysis investigation. All experimental results suggested that the 6% of Ho³⁺ dopant is the optimized level of ZnO host lattice. The present work paves a promising path to get efficient material for biomedical applications.

Keywords: Antimicrobial activities; Charge density; Photoluminescence; Rietveld refinement.