Morphology-controlled synthesis of hierarchical ball-flower metallic Co superstructures and their thermal catalytic property

Metallic Co with novel ball-flower architectures were successfully synthesized via a Polyvinylpyrrolidone (PVP) assisted hydrothermal reduction route. The ball-flowers were assembled by many nanoflakes with a side length of 50–100 nm and a thickness of about ∼10 nm, and the size gradually increased with the concentration of PVP. And the hierarchical Co with ball-flower architecture exhibited a high ferromagnetic characteristic with a saturation magnetization of about 90.0 emu/g and a coercivity of 207.0 Oe at room temperature. Importantly, the hierarchical Co architectures presented an excellent catalytic activity for thermal decomposition of ammonium perchlorate (AP) relative to commercial Co, Ni particles. This work might be potential important for providing a facile protocol to fabricate hierarchical metal superstructures with fascinating properties.