关键词: 活性炭, PbO, 石墨烯, 析氢, 超级电容器

Abstract: The lead oxide/graphene/activated carbon (PbO/GN/AC) composite materials were prepared by impregnating commercial activated carbon and graphene in saturated lead nitrate solution followed by calcination. The structures and morphologies of the composite were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). The results show that PbO crystals (about 200 nm) were dispersed uniformly on the surface of activated carbon and graphene. Electrochemical data indicate that the composite exhibited good electrochemical performances. The PbO/GN/AC composite possessed the higher over-potential of hydrogen evolution and the high specific capacitance of 312.6 F·g^-1, while the internal resistance was 1.56 Ω. The composite electrode also displayed excellent cycling stability, retaining over 92.6% of its initial charge after 6000 cycles. The ultra-battery with 5% (by mass) PbO/GN/AC being added to the negative paste had a cycle life approximately 3.5 times longer than conventional lead-acid batteries.

Key words: activated carbon, PbO, graphene, hydrogen evolution, supercapacitor