Lysine-assisted hydrothermal synthesis of urchin-like ordered arrays of mesoporous Co(OH)2 nanowires and their application in electrochemical capacitors

In the work, a novel lysine-assisted hydrothermal process is first developed to produce urchin-like ordered Co(OH)2 arrays, which are assembled from mesoporous Co(OH)2 nanowires. The synergistic contributions from lysine and Cl− ions to the formation of the unique arrays was also tentatively proposed. Electrochemical results show that the unique urchin-like ordered Co(OH)2 arrays show the ability to deliver large specific capacitance and good electrochemical stability at large current densities, which is reasonably ascribed to their ordered microstructure, hierarchical (meso- and macro-) porosity and good electronic conductivity. Moreover, the method we proposed here provides a universal green chemistry approach to large-scale production of Co(OH)2 and even other metal hydroxides oriented arrays with hierarchical porosity for fast energy storage.