Synthesis of Hollow Zinc Oxide Nanoparticles by Templating Micelles of Poly(styrene-b-acrylic acid-b-ethylene oxide) in Aqueous Solutions

摘要

Spherical hollow zinc oxide (ZnO) nanoparticles have been successfully synthesized by templating micelles of poly(styrene-b-acrylic acid-b-ethylene oxide) (PS-b-PAA-b-PEO). This polymer forms a micelle with a PS core, a PAA shell, and a PEO corona in aqueous solutions. Zinc chloride (ZnCl2) and sodium hydrogen carbonate (NaHCO3) were used as precursors of ZnO. In the synthesis, the PS core acts as a template for cavities of the hollow particles, the PAA shell is beneficial for arresting zinc ions for further mineralizing, and the PEG corona stabilizes the zinc hydrogen carbonate (Zn(HCO3)(2))/polymer nanocomposite to prevent secondary aggregate formation. Hollow ZnO nanoparticles were obtained after the calcination of the separated (Zn(HCO3)(2))/polymer nanocomposite at 500 degrees C for 4 h. The hollow ZnO nanoparticles were characterized by various techniques including transmission electron microscopy and X-ray diffraction analysis. The hollow ZnO particles have a spherical shape, a narrowly distributed size of 24.7 +/- 1.3 nm, and a shell thickness of 6.9 +/- 0.7 mm Compared with other methods, the present method gives hollow ZnO nanoparticles with smaller size (ca. 25 nm), narrow size distribution, controlled shape, and robust shell. This result strongly demonstrates the advantages of the present synthesis route.