Self-assembly and characterization of novel amorphous SiOx (x = 2.1) nanospheres

We report the self-assembly and characterization of amorphous SiOx nanospheres with diameters 210–240 nm. The preparation method was based on hydrolysation-induced self-assembly with Na2SiO3 as the silica precursor and polyacrylamide gels as the template. Ultraviolet and blue–green photoluminescence were observed at room temperature from amorphous SiOx nanospheres. The photoluminescence spectrum has peaks at 400 and 530 nm. From the x-ray photoelectron spectroscopy and energy disperse x-ray spectroscopy we found that the atomic ratio of Si to O is about 1:2.1. From the infrared spectrum and x-ray photoelectron spectroscopy, we suggest that the origin of the stable emission is Si–OH complexes located on the surface of the nanospheres. The silica nanospheres may have potential applications in future integrated optical devices.

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