Study of nanowires in botryoidal structure by the measurements of SEM and ESR

ABSTRACT

Polytetrafluoroethylene-modified silica/12-silicotungstic acid (abbreviated as HSiW/SiO₂-PTFE) catalyst was prepared by the ultrasonic impregnation method. The SEM results reveal there are a number of nanowires connecting microspheres with others, botryoidal structure. The diameters of these nanowires vary mainly from 30 nm to 60 nm. An asymmetric ESR signal is found in the ESR spectra of HSiW/SiO₂-30 wt% PTFE, which can be concluded to be peroxyl radical by spectral line shapes, g factor (2.0132).

KEYWORDS:

• Polytetrafluoroethylene
• botryoidal structure
• peroxyl radical
• SEM
• ESR
• ultrasonic impregnation method

Funding

This work was supported by the Educational Commission of Shandong Province of China (J10LB62).