Metal nitrides have great potential for electrochemical energy storage, but are relatively scarcely investigated. Herein, a novel metal nitride, Co₃N, is prepared by nitridation using a Co₃O₄ precursor heated at 500 °C for 2 h in flowing NH₃, and characterized by using X-ray diffraction (XRD), field emission-scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), selected area electron diffraction (SAED) and energy dispersive spectroscopy (EDS) methods. Besides, the electrochemical properties of Co₃N are investigated using cyclic voltammetry (CV), galvanostatic charge–discharge (GCD) and electrochemical impedance spectroscopy (EIS). The as-prepared Co₃N demonstrates remarkable electrochemical performance with a high specific capacitance of 112.3 F g⁻¹ at a current density of 0.5 A g⁻¹, good rate capability (72.4%, from 0.5 to 5 A g⁻¹) and superior cycling stability (109.7% retention over 10 000 cycles at a current density of 2 A g⁻¹). Finally, a Co₃N//activated carbon (AC) asymmetric supercapacitor (ASC) is successfully assembled by using Co₃N and AC as the positive electrode and negative electrode, respectively. The as-fabricated ASC device can achieve a maximum energy density of 12.1 W h kg⁻¹ at a power density of 204.6 W kg⁻¹, which shows that the Co₃N material should be a potential electrode material for supercapacitors.

中文翻译：

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氮原子间质化合物Co ₃ N的 固相合成和电化学拟电容

金属氮化物具有巨大的电化学能量存储潜力，但很少进行研究。在这里，一种新型的金属氮化物Co ₃ N是通过使用Co ₃ O ₄前驱体在流动的NH _3中在500°C下加热2 h进行氮化而制备的，其特征在于使用X射线衍射（XRD），场发射-扫描电子显微镜（FE-SEM），透射电子显微镜（TEM），选择区域电子衍射（SAED）和能量色散光谱（EDS）方法。此外，使用循环伏安法（CV），恒电流充放电（GCD）和电化学阻抗谱（EIS）研究了Co ₃ N的电化学性质。所制备的Co ₃Ñ显示了与112.3 F G高的比电容显着的电化学性能^-1以0.5 g的电流密度^-1，好的速率能力（72.4％，0.5至5 A G ^-1）和优异的循环稳定性（109.7％在2 A g ^-1的电流密度下保持超过10000次循环。最后，分别使用Co ₃ N和AC作为正极和负极，成功地组装了Co ₃ N //活性炭（AC）不对称超级电容器（ASC）。制成的ASC装置在204.6 W kg ^-1的功率密度下可以达到12.1 W h kg ^-1的最大能量密度，这表明Co ₃N材料应该是超级电容器的电位电极材料。