Anisotropic morphology, formation mechanisms, and fluorescence properties of zirconia nanocrystals

Abstract

ZrO 2 nanocrystals with spheres and elongated platelets were systemically prepared through a simple hydrothermal method by the use of ZrOCl 2 ·8H 2 O and CH 3 COOK as raw materials. The anisotropic morphology and formation mechanism of the monoclinic and/or tetragonal ZrO 2 were investigated by X-ray diffraction, Fourier transform infrared spectroscopy, Raman spectroscopy, scanning electron microscope, and high-resolution transmission electron microscope techniques. The uniform elongated platelets and star-like structures were composed of short nanorods with a diameter of approximately 5 nm and a length of approximately 10 nm. The different morphologies were formed due to the different contents of CH 3 COO − and Cl − and their synergy. The fluorescence band position and the band shape remained about the same for excitation wavelengths below 290 nm and the different morphologies of the nanocrystals.

Exciton Dynamics of MEH‐PPV polymer based Nanocomposites: Effect of Molecular Orbital Energy Levels of Nanoparticles**

“…The diffraction spots in the SAED pattern could be indexed to various planes corresponding to the tetragonal phase (t‐ZrO 2 ) and monoclinic phase (m‐ZrO 2 ). The electron powder‐diffraction pattern (Figure 4 (b)) displayed four diffraction rings, which indicates the (−111), (111) lattice plane of m‐ZrO 2 and (101), (200) lattice planes of t‐ZrO 2 [26] . The halo and diffuse rings depict the presence of crystallites of nanometric dimensions.…”

“…The electron powder-diffraction pattern (Figure 4 (b)) displayed four diffraction rings, which indicates the (À 111), (111) lattice plane of m-ZrO 2 and (101), (200) lattice planes of t-ZrO 2 . [26] The halo and diffuse rings depict the presence of crystallites of nanometric dimensions.…”

Endosseous Dental Implant Materials and Clinical Outcomes of Different Alloys: A Systematic Review

“…To avoid transitions from the tetragonal structure to the monoclinic structure when the compound cools, the molecule is stabilized with “doping” oxides, such as Y 2 O 3 , CeO 2 , MgO or CaO. This procedure confers considerable stability against microtraumatism, as well as the subsequent surface treatments to which the implants are subjected [ 73 , 74 ]. These treatments are: Sandblasting: this practice, also called abrasion with airborne particles, has the intent of imparting a roughness to the surface at a microscopic level, as opposed to what is obtained after only making the thread (the implant, in this case, is called “machined”).…”

Nanoparticles and Their Application in Prosthetic Dentistry

“…Sol-Gel Synthesis Method: It is difficult to control the structure during the production of nanoparticles. In the sol-gel synthesis method, nanoparticles can be obtained in desired sizes homogeneously and in different structures such as nanofibers, nanowires, nanotubes, flakes, flowers, and stars (8).…”