The NiCo2O4 ternary transition metal oxide (NCO) has been received a great interest as anode material for sodium-ion batteries, recently. Here we show that a composite material composed of NCO nanoparticles (NCO-NPs) and amorphous carbon (NCO/C composite) displayed a superior electrochemical performance over the NCO-NPs. The NCO-NPs delivered a capacity of 172 mAh g−1 at the current density of 50 mA g−1, and the capacity was reduced to 29 mAh g−1 after 50 cycles. The NCO/C composite showed a capacity of 213 mAh g−1 at 50 mA g−1; the capacity was lowered to 119 mAh g−1 after 100 cycles. The capacity of the composite at 100 mA g−1, 200 mA g−1 and 300 mA g−1 was ca. 123 mAh g−1, 93 mAh g−1 and 62 mAh g−1, respectively. This improvement is ascribed to the presence of the activated hard carbon of high electronic conductivity. Our work suggests that the combination of amorphous carbon with the NCO-NPs can serve as anodes for sodium-ion batteries.

中文翻译：

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混合无定形碳增强NiCo2O4纳米颗粒作为钠离子电池负极材料的电化学性能

最近，NiCo2O4 三元过渡金属氧化物 (NCO) 作为钠离子电池的负极材料受到了极大的关注。在这里，我们表明由 NCO 纳米粒子（NCO-NPs）和无定形碳（NCO/C 复合材料）组成的复合材料显示出优于 NCO-NPs 的电化学性能。NCO-NPs在50 mA g-1的电流密度下提供172 mAh g-1的容量，50次循环后容量降至29 mAh g-1。NCO/C 复合材料在 50 mA g-1 下的容量为 213 mAh g-1；100 次循环后容量降至 119 mAh g-1。复合材料在 100 mA g-1、200 mA g-1 和 300 mA g-1 下的容量约为。分别为 123 mAh g-1、93 mAh g-1 和 62 mAh g-1。这种改进归因于高电子导电性的活性炭的存在。