▎ 摘　　要

A supercapacitor material consisting of grapheme, Ni(OH)(2) and Ni foam (G/Ni(OH)(2)/NF) was prepared by a hydrothermal method, followed by a sputtering process. The electrochemical properties of resultant supercapacitors with different morphologies were also investigated. Among them, the supercapacitor based on nanoneedle array showed the best performance compared with other counterparts, with a larger area capacitance of 1.42 F cm(-2) and excellent cycling stability, maintaining ca. 80% of its initial capacitance after 3000 cycles. This study thus provides a facile method for preparing graphene/metal oxide composites with hierarchical structures for supercapacitors and other potential applications.