Two kinds of carbon microspheres (CMSs) were prepared by the hydrothermal method and chemical vapor deposition (CVD)

the CMSs prepared by CVD (CCMSs) were oxidized by a mixture of concentrated sulfuric acid and nitric acid (volume ratio of 3:1) to improve their surface activity

while the CMSs prepared by the hydrothermal method (HCMSs) were used as obtained. Then

two kinds of CMSs reacted with1

6-hexanediamine to prepare aminated CMSs with N

N'-dicyclohexyl carbodiimide as condensation agent. The morphology and structure of products were characterized with field emission scanning electron microscopy and Fourier transform infrared spectrometry. The thermostability and energy level structure were characterized with thermogravimetry and electrochemical analysis

the optical properties were characterized with fluorescence analysis. Both CMSs met the requirement of energy level as receptor materials in polymer solar cell

and amination increased the LUMO energy level of CMSs. HCMSs was superior to CCMSs in morphology

dispersibility in solvents and thermal stability

so HCMSs could be more suitable for using as the receptor materials of polymer solar cell.