The core shell structure of Cobalt@carbon nano rod/reduced graphene oxide (Co@CNR/rGO) is facilely synthesized with a one-pot hydrothermal process. Nitrogen is also introduced into the carbonaceous materials during the synthesis process. Calcination is added to graphitize the carbonaceous material, and simultaneously crystallize the Co particles. To assemble an electrode, the calcined Co@N-CNR/rGO material is uniformly loaded onto a collector of nickel foam by electrophoretic deposition. The specific capacitance is measured to be as high as 3233.3 F g^-1at a current density of 0.1 A g^-1. Three-dimensional rGO aerogels with desirable rate ability and cyclic stability are self-assembled with a hydrothermal reduction process from graphene oxide. Practically, the calcined Co@N-CNR/rGO and 3D rGO aerogel are utilized as cathode and anode to fabricate an asymmetric supercapacitor device, respectively. The operating voltage window of the device is increased to 1.5 V, and the energy density reached 31.8 Whkg⁻¹ at a power density of 302 W kg^-1, and 11.2 Whkg⁻¹ at 45,000 W kg^-1, respectively. The cyclic galvanostatic charge discharge stability is also measured and showed 99.2% capacity retention after 10,000 cycles at a current density of 5 A g^-1.

通过一锅水热法容易地合成了钴碳纳米棒/氧化石墨烯（Co @ CNR / rGO）的核壳结构。在合成过程中还将氮引入碳质材料中。添加煅烧以使碳质材料石墨化，并且同时使Co颗粒结晶。为了组装电极，将煅烧的Co @ N-CNR / rGO材料通过电泳沉积均匀地加载到泡沫镍的集电器上。比电容被测量为高达3233.3 F G ^-1在0.1 A g的电流密度^-1。具有所需速率能力和循环稳定性的三维rGO气凝胶通过氧化石墨烯的水热还原过程自组装。实际上，煅烧的Co @ N-CNR / rGO和3D rGO气凝胶分别用作阴极和阳极以制造不对称超级电容器。器件的工作电压窗口增加到1.5 V，功率密度为302 W kg ^-1时，能量密度分别为31.8 Whkg ^-1和45,000 W kg ^-1时分别为11.2 Whkg ^-1。还测量了循环恒静电荷放电稳定性，并在5 A g ^-1的电流密度下进行10,000次循环后显示99.2％的容量保持率。