Pan Denghui, Yang Haoyuan, Liu Yueyue, Wang Hui, Xu Tingting, Kong Dezhi, Yao Jingjing, Shi Yumeng, Li Xinjian, Yang Hui Ying, Wang Ye
Key Laboratory of Materials Physics, Ministry of Education, School of Physics and Microelectronics, Zhengzhou University, Zhengzhou 450052, P. R. China.
Center of Super-Diamond and Advanced Films (COSDAF) and Department of Chemistry, City University of Hong Kong, Hong Kong SAR, 999077, P. R. China.
Nanoscale. 2023 Nov 9;15(43):17482-17493. doi: 10.1039/d3nr03046f.
Sodium metal has emerged as a highly promising anode material for sodium-based batteries, owing to its intrinsic advantages, including its high theoretical capacity, low working plateau and low cost. However, the uncontrolled formation of sodium dendrites accompanied by unrestricted volume expansion severely limits its application. To tackle these issues, we propose an approach to address these issues by adopting a three-dimensional (3D) structure of TiCT/reduced graphene oxide (TiCT/rGO) constructed by a direct-ink writing (DIW) 3D printing technique as the Na metal anode host electrode. The combination of the 3D-printed rGO skeleton offering artificial porous structures and the incorporation of sodiophilic TiCT nanosheets provides abundant nucleation sites and promotes uniform sodium metal deposition. This specially designed architecture significantly enhances the Na metal cycling stability by effectively inhibiting dendrite formation. The experimental results show that the designed TiCT/rGO electrode can achieve a high coulombic efficiency (CE) of 99.91% after 1800 cycles (3600 h) at 2 mA cm with 2 mA h cm. Notably, the adopted electrodes exhibit a long life span of more than 1400 h with a high CE over 99.93% when measured with an ultra-high capacity of 50 mA h cm at 5 mA cm. Furthermore, a 3D-printed full cell consisting of a Na@TiCT/rGO anode and a 3D-printed NaV(PO)C-rGO (NVP@C-rGO) cathode was successfully demonstrated. This 3D-printed cell could provide a notable capacity of 85.3 mA h g at 100 mA g after 500 cycles. The exceptional electrochemical performance achieved by the 3D-printed full cell paves the way for the development of practical sodium metal anodes.
由于具有高理论容量、低工作平台和低成本等固有优势，金属钠已成为钠基电池极具前景的负极材料。然而，钠枝晶的无控制形成以及不受限制的体积膨胀严重限制了其应用。为了解决这些问题，我们提出了一种方法，即采用直接墨水书写（DIW）3D打印技术构建的三维（3D）TiCT/还原氧化石墨烯（TiCT/rGO）结构作为钠金属负极主体电极来解决这些问题。3D打印的rGO骨架提供人工多孔结构，以及亲钠性TiCT纳米片的掺入，两者相结合提供了丰富的成核位点，并促进钠金属的均匀沉积。这种特殊设计的结构通过有效抑制枝晶形成，显著提高了钠金属的循环稳定性。实验结果表明，设计的TiCT/rGO电极在2 mA cm²、2 mA h cm²的条件下循环1800次（3600小时）后，可实现99.91%的高库仑效率（CE）。值得注意的是，当在5 mA cm²的超高容量50 mA h cm²下测量时，所采用的电极具有超过1400小时的长寿命，CE超过99.93%。此外，成功展示了由Na@TiCT/rGO负极和3D打印的NaV(PO₄)₃C-rGO（NVP@C-rGO）正极组成的3D打印全电池。这种3D打印电池在500次循环后，在100 mA g⁻¹的电流下可提供85.3 mA h g⁻¹的显著容量。3D打印全电池实现的优异电化学性能为实用钠金属负极的开发铺平了道路。
