Key Laboratory of Mesoscopic Chemistry of MOE and Collaborative Innovation Center of Chemistry for Life Sciences, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, Jiangsu 210093, China.
Nanoscale. 2017 Feb 2;9(5):1972-1977. doi: 10.1039/c6nr08296c.
Here we report an effective bottom-up solution-phase process for the preparation of nitrogen-doped porous carbon scaffolds (NPCSs), which can be employed as high-performance anode materials for both lithium-ion batteries (LIBs) and sodium-ion batteries (SIBs). The as-obtained NPCSs show favorable features for electrochemical energy storage such as high specific surface area, appropriate pore size distribution (3.9 nm in average), large pore volume (1.36 cm g), nanosheet-like morphology, a certain degree of graphitization, enlarged interlayer distance (0.38 nm), high content of nitrogen (∼5.6 at%) and abundant electrochemically-active sites. Such a unique architecture provides efficient Li/Na reservoirs, and also possesses smooth electron transport pathways and electrolyte access. For LIBs, the anodes based on NPCSs deliver a high reversible capacity of 1275 mA h g after 250 cycles at 0.5 C (1 C = 372 mA g), and outstanding cycling stabilities with a capacity of 518 mA h g after 500 cycles at 5 C and 310 mA h g after 1500 cycles even at 10 C. For SIBs, the anodes based on NPCSs display a reversible capacity of 257 mA h g at 50 mA g, and superior long-term cycling performance with a capacity of 191 mA h g after 1000 cycles at 200 mA g.
我们在此报告了一种有效的自上而下的溶液相法制备氮掺杂多孔碳支架（NPCSs）的方法，该支架可用作锂离子电池（LIBs）和钠离子电池（SIBs）的高性能阳极材料。所获得的 NPCSs 具有电化学储能的有利特征，例如高比表面积、适当的孔径分布（平均 3.9nm）、大孔体积（1.36cm³g）、纳米片状形态、一定程度的石墨化、增大的层间距离（0.38nm）、高氮含量（约 5.6at%）和丰富的电化学活性位点。这种独特的结构提供了高效的 Li/Na 储存库，并且还具有平滑的电子传输途径和电解质的通道。对于 LIBs，基于 NPCSs 的阳极在 0.5C（1C=372mA g）下循环 250 次后可提供 1275mA h g 的高可逆容量，在 5C 下循环 500 次后可提供 518mA h g 的出色循环稳定性，甚至在 10C 下循环 1500 次后仍可提供 310mA h g 的容量。对于 SIBs，基于 NPCSs 的阳极在 50mA g 下可提供 257mA h g 的可逆容量，在 200mA g 下循环 1000 次后可提供 191mA h g 的出色长期循环性能。
