Solid-State Thermolysis Preparation of Co3O4 Nano/Micro Superstructures From Metal-Organic Framework for Supercapacitors

We describe here a novel strategy for the preparation of Co3O4 nano/micro superstructures from a cobalt ion-based metal-organic framework (MOF). First, cobalt ion-based coordination polymer with metal-organic framework was synthesized through solvothermal method by using p-benzenedicarboxylic acid (p-H2BDC) as ligand. Second, porous Co3O4 nano/micro superstructures were prepared from solid-state annealing of MOF precursor at 450 ˚C; for 2 h. The resulting superstructures were assembled by porous microsheet building blocks, which primarily composed of uniform nanoparticles. When used as electrode material of supercapacitors, the as-prepared porous Co3O4 superstructures exhibited a specific capacitance of 208 F·g-1 at the current density of 1 A·g-1 and a specific capacitance retention of ca. 97% after 1000 continuous charge-discharge cycles in 6.0 M aqueous KOH solution (vs. SCE), suggesting their potential applications for supercapacitors.