| Core shell structure particles are novel ordered assembly structures on nanometer scale, which are synthesized through chemical bond or other interaction between two materials. The surface charge, functional groups, and reaction properties of core materials are tailored by coating of shell materials, which improves the stabilization and dispersion of core materials. The Luminescence of core shell structure particles would be enhanced to apply in biological labels and other fields by doping or surface plasmon resonance.In the paper, SiO2@CdS, SiO2@ZnS and Au@SiO2 core shell particles have been fabricated successfully, as well as the CdS and ZnS hollow microspheres. The structure and optical properties of core shell microspheres and hollow microspheres were investigated with TEM, XRD, UV-Vis and PL. The main results achieved in this paper are listed as following:1. SiO2@CdS core shell microspheres were synthesized by a chemical bath deposition (CBD) method. Then silica cores were etched by HF and CdS hollow microspheres were obtained. By reducing the amount of Cd2+ and S2- source, or decreasing the reaction temperature, the thickness of CdS shell would be decrease from 30 nm to 10 nm. The absorption edge of SiO2@CdS core shell microspheres blue-shifted from 515 run to 455 nm with the decrease of shell thickness. The photoluminescence of SiO2@CdS core shell microspheres was mainly located at 525 nm, which was attributed to the light emission from defects level. The optical properties of CdS hollow microspheres were same as the SiO22@CdS core shell microspheres.2. SiO2@ZnS core shell microspheres and ZnS hollow microspheres were synthesized by an ultrasonic-assisted chemical deposition method. By reducing the amount of Zn2+ and S2- source, the thickness of ZnS shell would be decrease from 15 nm to 10 nm. The absorption edge of SiO2@ZnS core shell microspheres blue-shifted from 337 nm to 324 nm. The photoluminescence of SiO2@CdS core shell microspheres was mainly located at 430 nm, which was also attributed to the light emission from defects level.3. The SiO2@ZnS core shell microspheres were treated by 140℃-300℃ annealing. However, the optical properties of SiO2@ZnS were not improved. On the other hand,the manganese(Mn) doping improved the luminescence of SiO2@ZnS. One stable and narrow emission peak at 590 nm was observed which was attributed to Mn-doped level in the bandgap of ZnS. It was worth to note that the doping was efficient only the concentration of Mn2+ source was less than 5 at. %.4. Au colloids with 12 nm-100 nm size were synthesized by reduction of sodium citrate. The size increase of Au resulted in the red-shift of surface plasmon resonance peak of Au from 520 nm to 550 nm. Then Au@SiO2 core shell nanoparticles were obtained through coating SiO2 on colloidal Au surface by a Stober method. The SiO2 coating also made surface plasmon resonance peak of Au red-shift. Besides, the photoluminescence of SiO2@ZnS: Mn core shell and ZnS hollow microspheres was enhanced through the coupling with the surface plasmon of Au.
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