Density functional theory analysis of novel ZrO2 polymorphs: Unveiling structural stability, electronic structure, vibrational and optical properties
Kanimozhi Balakrishnan, Vasu Veerapandy, V. Nalini, Ponniah Vajeeston
Abstract
• Three ZrO 2 polymorphs with TiO 2 origins—mp-1840, mp-9173, and mp-754769, are revealed for the first time. • DFT calculations at 0 K and zero pressure reveal stability trends by analyzing total energy relative to volume. • Reported spatial dependence moduli for ZrO 2 polymorphs. • Distinct IR and Raman fingerprint regions identified for stable ZrO 2 polymorphs. • ZrO 2 polymorphs have bandgaps of 4.1–5.5 eV, ideal for UV photon absorption and photovoltaic use. The importance of advanced materials like zirconium dioxide (ZrO 2 ) in diverse medical, industrial, and technological contexts is underscored by contemporary technology. ZrO 2 ′s unique combination of properties renders it indispensable for a broad spectrum of applications, suggesting its enduring importance. This study presents the very first investigation into the physical properties, structural stability, and ground-state characteristics of sixteen distinct ZrO 2 polymorphs through the application of density functional theory (DFT). Motivated by the potential of ZrO 2 polymorphs to substitute for SiO 2 , we conducted calculations to ascertain their dielectric properties. A comprehensive analysis was conducted on all structural features, and their stability was assessed. ZrO 2 polymorphs exhibit a wide bandgap with the type of bandgap also examined. Calculated zone-center phonon frequencies demonstrate the dynamical stability of ZrO 2 , with existing polymorphs showing strong agreement with experimental frequencies, particularly within the monoclinic polymorph. Raman and infrared (IR) spectra of ZrO 2 polymorphs were simulated using density functional perturbation theory. ZrO 2 demonstrates notable mechanical stability, as evidenced by calculated hardness (moduli), ductility, improved ductility, and higher elasticity. Calculated optical properties, including the dielectric constant and refractive index of ZrO 2 polymorphs, play a pivotal role in optimizing their performance in various applications such as optoelectronic devices and antireflective materials.