Geng Jitao, Dong Huilong, Liu Jing, Lv Chengkui, Wei Huaixin, Cheng Yafei, Yang Jun, Geng Hongbo
School of Materials Engineering, Changshu Institute of Technology, Changshu, Jiangsu, 215500, China.
School of Chemistry and Life Sciences, Suzhou University of Science and Technology, Suzhou, 215009, China.
Nanoscale. 2023 Sep 14;15(35):14641-14650. doi: 10.1039/d3nr03182a.
The progress of sodium-ion batteries is currently confronted with a noteworthy obstacle, specifically the paucity of electrode materials that can store large quantities of Na in a reversible fashion while maintaining competitiveness. Herein, ultrafast and long-life sodium storage of metal selenides is rationally demonstrated by employing micron-sized nanosheets (Cu-CoSe@NC) through electron accumulation engineering. The nanosheet structure proves to be effective in reducing the transport distance of sodium ions. Furthermore, the addition of Cu ions enhances the electron conductivity of CoSe and accelerates charge delocalization. As an anode for sodium-ion batteries, Cu-CoSe@NC exhibits a noticeably enhanced specific capacity of 527.2 mA h g at 1.0 A g after 100 cycles. Additionally, Cu-CoSe@NC maintains a capacity of 428.5 mA h g at 5.0 A g after 800 cycles. It is possible to create sodium-ion full batteries with a high energy density of 101.1 W h kg. The superior sodium storage performance of Cu-CoSe@NC is attributed to the high pseudo-capacitance and diffusion control mechanisms, as evidenced by theoretical calculations and measurements.
钠离子电池的发展目前面临着一个值得注意的障碍，具体而言，是缺乏能够以可逆方式大量存储钠同时保持竞争力的电极材料。在此，通过电子积累工程，利用微米级纳米片（Cu-CoSe@NC）合理地证明了金属硒化物的超快和长寿命钠存储性能。纳米片结构被证明在减少钠离子传输距离方面是有效的。此外，铜离子的加入提高了CoSe的电子导电性并加速了电荷离域。作为钠离子电池的阳极，Cu-CoSe@NC在1.0 A g下经过100次循环后，展现出显著增强的比容量，达到527.2 mA h g。此外，Cu-CoSe@NC在5.0 A g下经过800次循环后，仍保持428.5 mA h g的容量。有可能制造出能量密度高达101.1 W h kg的钠离子全电池。理论计算和测量结果表明，Cu-CoSe@NC优异的钠存储性能归因于高赝电容和扩散控制机制。
