Effects of reaction temperature and contact mode between reagents on Cu (OH)2 micro/nanostructures and their supercapacitive properties

A simple reaction between copper wire (CW) and ammonia water (NH3 center dot H2O) is developed to directly synthesize Cu(OH)2 with different micro/nanostructures on the CW surface as flexible electrodes for supercapacitors. The morphology and structures can be tailored under various reaction temperatures and contact modes between CW and NH3 center dot H2O. Cu(OH)2 nanosheets on the surface of CW obtained by an in-situ growth strategy can provide abundant electroactive sites and shorten ion diffusion pathway for its application in the electrode. The CW@Cu (OH)2 flexible electrode delivers excellent electrochemical performances, such as 38.91 F cm-3 and 200.5 mF cm-2 at a current density of 0.3 A cm-3. At the same time, the CW@Cu(OH)2 electrode also exhibits a good cycling stability, the specific capacitance of which can maintain 82.8 % after 6000 cycles.