Preparation and self-assembly of chitosan/carbon microsphere composite

Carbon-based films were synthesized by self-assembly of chitosan-encapsulated carbon microsphere (CMS@CS) composite. First, carbon microspheres (CMSs) prepared by chemical vapor deposition were modified by HNO3 and H2O2. Second, oxidized CMSs were modified by chitosan (CS). Finally, CMS@CS was self-assembled by vertical deposition, in which suspension concentration and deposition temperature on the quality of self-assembling film were investigated. Field emission scanning electron microscopy, atomic force microscopy, X-ray diffraction, thermogravimetry, and Fourier transformation infrared spectrometry were employed to characterize the morphology and structure of the samples. The results show that CMSs modified by CS had uniform particle size and good dispersion, CMS@CS was self-assembled into a dense film, the film thickened with increasing suspension concentration at fixed temperature, and more ordered film was obtained at 1 wt% of suspension concentration and 50 A degrees C. The ultraviolet-visible absorption spectra show that the absorbance of CMS@CS film grew steadily with increasing suspension concentration and that the CMSs with oxygen-containing groups have a good assembling performance to form composite films with CS.