Preparation of flower-like CuO by a simple chemical precipitation method and their application as electrode materials for capacitor

A novel CuO electrode material with flower-like nanostructures was fabricated at a low temperature (80 deg. C) by a simple chemical precipitation method. Scanning electron microscopy (SEM) results showed that CuO with spherical and flower-like structure can be formed under a weak alkali (C{sub 6}H{sub 12}N{sub 4}), and CuO with sheets structure can be obtained under a strong alkali (NaOH). A possible growth mechanism of CuO nanocrystals was discussed. The flower-like CuO electrode exhibited a higher specific capacitance (133.6 Fg{sup -1}) and an excellent cycle performance at a high current density of 10 mA/cm{sup 2}. Specific capacitance of flower-like CuO was 405.3% higher than globular CuO (26.44 Fg{sup -1}) at 2 mA/cm{sup 2}.