Monodisperse BaF₂ Nanocrystals: Phases, Size Transitions, and Self‐Assembly

Abstract

Monodisperse kubische und orthorhombische BaF2‐Nanokristalle wurden mithilfe der LSS‐Methode (liquid–solid–solution) gebildet. Das Keimwachstum ist kinetisch kontrolliert, und die Größe und Morphologie der Keimkristalle hängen stark von der Reifungszeit und der Tensidkonzentration ab (siehe Schema). Die BaF2‐Kristallphasen entstehen dann thermodynamisch kontrolliert.

Shape-controlled synthesis of phosphor K2SiF6:Mn4+nanorods and their luminescence properties

“…Therefore, all this information on morphologies indicates that an appropriate KMnO 4 content leads to complete and perfect K 2 SiF 6 crystal growth. We can find some evidence to support this point: solvothermal synthesis of NaYF 4 nanocrystals, 21 self-assembled cubic-phase and orthorhombic-phase BaF 2 nanocrystals synthesized by LSS, 22 time-dependent growth of CeF 3 nanoparticles 12 and the synthesis of highly uniform and monodisperse Ba 2 ClF 3 microrods. 15 3.2.3.…”

Nucleation and Growth of CeF3 and NaCeF4 Nanocrystals

“…To meet this challenge, recently, our group has developed a surface chemical thermodynamics (SCT) [5] model to explain the nucleation and growth mechanism of Ba 2 F 3 Cl nanorods and nanowires based on thermodynamics; moreover, the SCT model has been successfully applied to interpret the size transition of orthorhombic BaF 2 nanorods. Very recently, we have substantiated a diffusion-controlled kinetic (DCK) [6] model based on experimental results, and have used this model to explain the growth mechanism of both cubic phase and orthorhombic phase BaF 2 nanocrystals. The SCT and DCK models coordinate smoothly and explain the effect of thermodynamics and kinetics, respectively, on BaF x Cl 2-x nanocrystal growth.…”

“…Since the size transition of CeF 3 nanoparticles took place in nonequilibrium conditions, this process was investigated by using the DCK model developed in our previous work. [6] The DCK model is based on the assumption that under such growth conditions, different crystal surfaces have different kinetic parameters. Therefore, the monomer reaction rates of the longitudinal and radius directions of CeF 3 nanocrystals may be quite different, see Equation (1), in which, the subscripts 1 and 2 represent the longitudinal and radius direction, respectively; D 1 and D 2 are diffusion coefficients; s 1 and s 2 are corresponding surface areas; R eff is the effective radius, [n] is the concentration of the nanocrystals, and [A] is the CeF 3 monomer concentration.…”

Bromine Precursor Mediated Synthesis of Shape Controlled Cesium Bromide Nanoplatelets and Their Mechanism Study by DFT Calculation

“…Additionally, to describe the relationship between the CsBr crystal size and temperature in this experiment, we referred to the surface chemical thermodynamics (SCT) model. − The SCT model was developed based on the fundamental thermodynamic potential of Gibbs free energy where γ is the specific surface energy, σ is the surface area, and μ is the chemical potential of component i . The reaction proceeded under the solution phase; thus, dP was assumed to be zero.…”