A high-performance battery-supercapacitor hybrid device based on bimetallic hydroxides nanoflowers derived from metal-organic frameworks

[Display omitted] A facile alkaline treatment stripping precursor strategy is developed for preparing MOF derived double hydroxide. The bimetallic MOFs material provides multi-type of redox reaction centres, and the hydroxide nanonanoflower obtained by alkali stripping Ni-MOF@Co-MOF effectively expands the “active area (circumference)” of the redox reaction. The exfoliated sheets expose more active sites, which are more favorable for effective contact with the electrolyte and facilitate the occurrence of redox reactions. The MOF derived double hydroxide maintains the structural and performance advantage of the MOF precursor as well as overcomes the disadvantages of poor conductivity and serious agglomeration of common hydroxide. As-synthesized electrode exhibited high specific capacity of 1088 C g−1 at 1 A g−1 and cycle retention of 94% after 12,000 cycles. Furthermore, assembled battery-supercapacitor hybrid device exhibits a maximum energy density of 66.5 Wh kg−1 at a power density of 825 W kg−1, and superior cycle retention and coulombic efficiency of 86% and 95% after 18,000 cycles, which shows that Ni-MOF@Co-MOF derived double hydroxide has good potential application value.