Abstract:

In this paper, silica hollow nanoparticles(SHNs) with quite uniform particle sizes were prepared by reverse microemulsion system. High resolution transmission electron microscopy(HRTEM) and field emission scanning electron microscopy(FESEM) were used to characterize the structure of SHNs. The carbon dots and silica hollow nanoparticles composite(CD-SHN) was prepared by hydrothermal treatment of self-assembled SHNs in presence of citric acid and ethylene diamine. FESEM images show that the average diameter of sea anemone-like carbon dots-silica nanocomposite is about 1 μm. The size of silica hollow nanosphere is between 30~40 nm, and shell thickness is 10 nm. The CD-SHN demonstrates multicolor fluorescence emission, and high photostability. The maximum excitation and emission wavelengths of CD-SHN are 360 nm and 435 nm, respectively, and 97% of the fluorescence intensity can be retained after being excited for 60 min by a 40 W incandescent lamp. Due to the mild preparation conditions and good biocompatibility of the materials, the composite material has the potential application in biological imaging.

Key words: hollow nanostructure, sea anemone-like, carbon dots, silica, multicolor fluorescence