CoO nanoflowers woven by CNT network for high energy density flexible micro-supercapacitor

Miniaturized energy storage devices have attracted considerable research attention due to their promising applications in future. In this work, we employ an easy screen printing method to fabricate a flexible micro-supercapacitor (MSC) device with a novel three dimensional (3D) nanocomposite of CoO/CNT (i.e. CoO and carbon nanotube (CNT)) as active material. Due to wide operation voltage window (1.2 V), the energy density can reach ~3.48 mWh/cm3 for this CoO/CNT based MSC, which is much better than that of CoO or CNT based MSC. In addition, the printed CoO/CNT based MSCs also show remarkable cycling stability with ~85% energy density retention after 1700 cycles and high mechanical flexibility which can function well even after bending up to 180°.