Figure 2

(a) C1s and (b) O1s spectra of XPS study; (c) Oxygen content and C/O (atom/atom) of hollow microspheres by using XPS spectroscopy and SEM-EDS element analysis; (d) The dispersibility of PS hollow microspheres in water, ethanol, DMSO, DMF and Toluene solution, respectively. The reaction condition was the same as Fig. 1.