“…It has been proved that cobaltosic oxide with different morphologies and microstructures should present different properties [14]. Up to now, lots of different Co 3 O 4 morphologies and sizes, such as nanowire [15], nanorods [16,17], nanosheet [13,18,19], nanonet [11], nanocubes [3], nanotubes [20], nanowalls [21], urchin-like [4,22] and porous hollow polyhedra [12,23], etc. have been synthesized successfully through various methods, that is, CBD method, hydrothermal method, template-assisted method, solvothermal method and thermal oxidation [7,15,19,24,25].…”