Confined space synthesis of Ni(OH)2-impregnated three-dimensional ordered mesoporous carbon as a high-performance supercapacitor electrode
Huiyong Chen, Xin Yang, Wencheng Yang, Siyu Zhang, Xingrui Wang, Baoyu Liu, Chengyi Dai, Jianbo Zhang, Xiaoxun Ma
Abstract
Regulable loading of Ni(OH)2 crystals by using three dimensionally ordered mesoporous carbon (3DOMC) as a support is achieved through a confined growth strategy accompanied by steam-assisted crystallization. Dual forms of high-crystalline nanosheet-like Ni(OH)2 severally distribute within mesopores or over the outer surface of 3DOMC particles depending on the loading amount (3% − 15%) of Ni(OH)2. Benefitted from the highly hybrid combination and efficient electrolyte diffusion, the obtained Ni(OH)2/carbon nanocomposites exhibit an excellent electrochemical performance, and the optimal sample of 6%_Ni(OH)2/3DOMC with confined extra-small Ni(OH)2 nanosheets as dominant shows the highest specific capacitance of 552.5F.g−1 at 1.0A·g−1, which is 330% higher than the contrast sample by using actived carbon as the support. Furthermore, the assembled hybrid supercapacitor by using 6%_Ni(OH)2/3DOMC and 3DOMC as positive and negative electrodes displays an energy density of 11.7 Wh.kg−1 at 288.1 W.kg−1 and a superior charge/discharge stability. It is expected that the flexible component, well-defined structure, and superior electrochemical performance could promote a great application potential of Ni(OH)2/3DOMC nanocomposites as supercapacitor electrodes and in other energy storage devices.