Abstract:Cerium dioxide(CeO2) was modified by carboxylation to get carboxylated cerium oxide (CeO2-COOH), and a graft polymerization took place between CeO2 and aniline (An) to get core-shell structured polyaniline composites(PANI/CeO2-COOH). The structure and properties of the materials were analyzed by FT-IR, XPS, XRD, TGA, SEM and rotating disk electrochemical testing. The results reveal that the CeIII/CeIV ratio of CeO2-COOH is approximately 1 with high surface oxygen vacancies. Meanwhile, the core-shell structured PANI/CeO2-COOH composite has the best grafting morphology, and the structure of PANI on the surface of CeO2-COOH is the same with pure PANI. PANI/CeO2-COOH is grafted via the valence bond between CeO2-COOH and PANI and shows the best thermal stability, where PANI/CeO2-COOH has the initial decomposition temperature at about 228 ℃ and the lowest decomposition rate in the range of 200~600 ℃. Cyclic voltammetry and galvanostatic charge-discharge tests were performed on composite electrodes in 1 mol/L H2SO4. The PANI/CeO2-COOH electrode not only has excellent peak symmetry and the highest anodic peak current, but also has higher capacitance performance, where the specific capacitance reaches 149.5 F/g with the current density of 0.5 A/g.