Shape-controlled synthesis of Ni-CeO2@PANI nanocomposites and their synergetic effects on supercapacitors

Nickel-doped cerium oxide [email protected] (Ni-CeO2@PANI) was prepared through a facile two-stage synthetic method composed of hydrothermal and polymerized reactions. Addition of HCl affects the morphology control and electrochemical performance of Ni-CeO2@PANI nanocomposites. The nanocomposites were characterized using several techniques. With increasing amount of HCl, various shape-controlled nanocomposites, such as non-spacing core-shell Ni-CeO2@PANI nanospheres (NCP1), yolk-shell Ni-CeO2@PANI nanospheres, and PANI hollow spheres, were prepared. Ni-CeO2@PANI nanocomposites, as an electrode material, were fabricated into supercapacitors and characterized using cyclic voltammetry, electrochemical impedance spectroscopy, and galvanostatic charge–discharge measurements. Results showed synergetic effects on NCP1, where capacitance and stability were derived from the PANI component and Ni-CeO2, respectively. This material exhibited high specific capacitance (866 F g−1 at 1 A g−1), high energy density (120.3 Wh kg−1), and excellent cycling stability (85.6% remaining content after 10,000 number cycles).