It is well known that long term stability in zirconia has been a problem because of the structural alteration from stabilized tetragonal zirconia to monoclinic that leads to fracture in implants. Microwave (MW) assisted sol-gel synthesis is employed in the present work to prepare stabilize zirconia nanoparticles. ZrOCl₂.8H₂O is used as a precursor whereas de-ionized water is used as a solvent. Power of microwave radiations is varied in the range of 100–1000W. Zirconia nanoparticles have been characterized under as-synthesized, 6- and 12-months’ room temperature (RT) aged conditions. Metastable phase (MP) of zirconia, appearing under as-synthesized conditions, transforms to phase pure tetragonal zirconia (t-ZrO₂) after RT aging that was prepared with MW powers of 100, 200 and 700–1000W. Whereas, MP transforms to mixed tetragonal-monoclinic phases at microwave powers of 300–600W after RT aging. XPS results show presence of oxygen-deficient state of ZrO₂ lattice along with surface defects contributing towards the tetragonal zirconia phase under all conditions. Value of dielectric constant (i.e. ~11–12 at log f = 4.0), hardness (~13 GPa) and fracture toughness observed under all conditions are well in agreement to be used for biological implants. Disks of aged t-ZrO₂ nanoparticles are checked for their biodegradation test by dipping in simulated body fluid for several weeks. ZrO₂, with 26 weeks of immersion, shows small loss in hardness and weight. Stabilized tetragonal zirconia shows strong anti-oxidant activity. Stabilized ZrO₂ nanoparticles presented strong antibacterial activity against both gram positive (S. aureus, Bacillus) and gram negative (E. coli) bacteria. Thus, structural and mechanical stability of zirconia (checked after 6 and 12 months) make this material highly beneficial for long term use in biomedical applications.

众所周知，由于从稳定的四方氧化锆到单斜晶的结构变化导致植入物的断裂，因此氧化锆的长期稳定性一直是一个问题。在本工作中采用微波（MW）辅助的溶胶-凝胶合成来制备稳定的氧化锆纳米粒子。ZrOCl ₂ .8H ₂ O被用作前体，而去离子水被用作溶剂。微波辐射的功率在100–1000W的范围内变化。氧化锆纳米粒子已经在合成的6个月和12个月的室温（RT）老化条件下进行了表征。在合成条件下出现的氧化锆亚稳相（MP）转变为纯四方相氧化锆（t-ZrO ₂）在RT老化之后，准备了100、200和700–1000W的MW功率。RT老化后，MP在300–600W的微波功率下转变为混合的四方单斜相。XPS结果表明，在所有条件下，ZrO ₂晶格都存在缺氧状态，并且表面缺陷有助于四方氧化锆相。 在所有条件下观察到的介电常数（即，log f = 4.0时为〜11–12），硬度（〜13 GPa）和断裂韧性的值完全一致，可用于生物植入物。通过浸入模拟体液中数周来检查老化的t-ZrO ₂纳米颗粒盘的生物降解测试。氧化锆₂浸泡26周后，硬度和重量的损失很小。稳定的四方氧化锆具有很强的抗氧化活性。稳定的ZrO ₂纳米颗粒对革兰氏阳性菌（金黄色葡萄球菌，芽孢杆菌）和革兰氏阴性菌（大肠杆菌）均具有很强的抗菌活性。因此，氧化锆的结构和机械稳定性（在6个月和12个月后检查）使该材料非常适合长期用于生物医学应用。