Microwave-assisted green synthesized ZnO nanoparticles: an experimental and computational investigation

Abstract

Abstract This research presents a comprehensive experimental and computational analysis of ZnO nanoparticles (NPs) employing DFT alongside advanced characterization methods. The green synthesized ZnO NPs were subjected to analysis via FTIR spectroscopy for the identification of functional groups, HR-TEM for the evaluation of morphology, and XRD for the determination of their crystalline structure. The XRD analysis disclosed accurate lattice parameters, including a = 3.2497 Å, c = 5.2122 Å, bond lengths measuring 1.978 Å, and crystallite sizes determined to be 14.06 nm through Scherrer’s equation and 20.14 nm via the W–H method, all of which correspond to the acceptable range. The computational analyses revealed bond lengths of 1.966 Å and a band gap of 4.13 eV. The analysis of quantum chemical parameters, frontier molecular orbitals, density of states, and band structures derived from optimized ZnO NPs offers insights into their electronic properties at the nanoscale. The principal findings encompass a robust alignment between experimental and computational results, an increased band gap attributed to confinement, and strain-induced modifications to crystal characteristics, illustrating the collaborative potential of computational and experimental methodologies in optimizing the properties of ZnO NPs for advanced applications. Graphical Abstract

Keywords

• ZnO NPs
• Green synthesis
• DFT
• XRD
• Quantum chemical parameters
• Frontier molecular orbitals