2018, Vol.28, No.3

Journal of the Korean Crystal Growth and Crystal Technology 2023 KCI Impact Factor : 0.19

pISSN : 1225-1429 / eISSN : 2234-5078
https://journal.kci.go.kr/jkcgct

In order to avoid un-uniform crystallization on the surface of a quartz glass crucible that is known to affect the production yield of the single crystal silicon, Ba (barium) was selected as a crystallization promotor and the inner surface of the crucible was coated using Ba (barium hydroxide octahydrate)-solution by the spray pyrolysis method. For un-coated crucible, it was found that the crystallization of its surface started at 1350 o C, and at 1450 o C the surface was uniformly crystallized with β-cristobalite phase. It was found that the crucible coated with Ba began to be crystallized from 1000 o C and was uniformly crystallized on the crucible surface at 1300 o C. In this case, α-cristobalite and needle-shaped BaSi2O5 phase were created and disappeared as a crystal phase, and the β-cristobalite phase was eventually evenly distributed over the Ba-coated crucible surface.

Halide perovskite nanocrystals have become attractive for LED applications due to their high color purity and excellent luminescent properties. CsPbX3 (X = I, Br, and Cl) nanocrystals were synthesized by hot-injection method and the emission wavelength was controlled by changing the composition of halide ion. Green- and red-emitting films were fabricated using a polymer binder. The outstanding optical properties of the synthesized nanocrystals and fabricated films were confirmed. The wLED designed by green- and red-emitting perovskite nanocrystal films on blue InGaN LED was characterized.

The metal alkoxide, CuCo-glycerate nanospheres (NSs), were successfully synthesized as Cu-Co bimetallic sulfides hierarchical multi-shelled hollow nanospheres (CuCo2S4 HMHNSs) through solvothermal synthesis. In this reaction mechanism, the solvothermal temperature and the amount of glycerol as a cosurfactant play significant role to optimize the morphology of CuCo-glycerate NSs. Furthermore, CuCo2S4 HMHNSs were obtained under optimized sulfurization reaction time of 10 h via anion exchange reaction between glycerate and sulfur ions. Finally, the structural and chemical compositions of CuCoglycerate NSs and CuCo2S4 HMHNSs were confirmed through field emission scanning electron microscopy (FESEM), transmission electron microscope (TEM), X-ray diffraction (XRD) and electrochemical performances.