▎ 摘　　要

A conception of "waste from the power should be used for the power" was established for sustainable energy development in the present work. Series of MnO2/graphene nanocomposites have been prepared via a facile physical mixing method as the electrode materials for supercapacitors with the spent battery powder (SBP) as raw material, which was obtained from the spent Zn-MnO2 acidic dry batteries via simple processing. The structure and morphology of the resulting composites were characterized by FT-IR, Raman, XRD, TEM, and SEM. The electrochemical tests showed that the as-obtained SBP had low impedance and excellent cyclic stability of retaining 100% of its initial capacitance after 1000 cycles. After the incorporation of the carbon substrates (graphene oxide (GO) or reduced graphene oxide (rGO)), the capacitance was enhanced more than 2 times the original SBP (66 F/g), which can be attributed to the synergistic effect of the carbon materials and the metal oxide. The present work would lead to new insight into the recycling of waste batteries.