To improve the dispersibility of carbon microspheres (CMSs)

their surfaces were first oxidized by a mixture of concentrated HNO3 and H2O2.Then oxidized-CMSs were self-assembled by vertical deposition

and the effects of solvent

pH value of the suspension

suspension concentration and reaction temperature on self-assembly were investigated.The morphologies of all samples were characterized by field emission scanning electron microscopy and atomic force microscopy.The results showed that the CMSs film with more ordered and denser structure was obtained using NaOH solution as solvent for preparing suspension

at suspension concentration of 2%（mass）

pH of 13 and deposition temperature of 50℃.The sample showed good reflection of light with uniform color

which indicated the formation of uniform CMSs film.