Duan Zhixia, Zhang Xiaoling, Xu Junmin, Chu Ningning, Zhang Jinwei, Ji Mengfan, Wang Xinchang, Kong Dezhi, Wang Ye, Chu Paul K
Key Laboratory of Materials Physics, Ministry of Education School of Physics, Zhengzhou University, Zhengzhou, 450001, China.
Department of Physics, Department of Materials Science and Engineering, and Department of Biomedical Engineering, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, 999077, China.
Small. 2024 Nov;20(47):e2405430. doi: 10.1002/smll.202405430. Epub 2024 Aug 22.
A 3D-printed oxygen-vacancy-rich potassium ammonium vanadate/reduced graphene oxide (KNVO/rGO) microlattice aerogel is designed for the cathode in high-performance K-ion batteries (KIBs). The 3D-printed KNVO/rGO electrode with periodic submillimeter microchannels and interconnected printed filaments is composed of highly dispersed KNVO nanobelts, wrinkled graphene nanoflakes, and abundant micropores. The well-defined 3D porous microlattice structure of the rGO backbone not only provides the interconnected conductive 3D network and the required mechanical robustness but also facilitates the penetration of the liquid electrolyte into inner active sites, consequently ensuring a stable electrochemical environment for K-ion intercalation/deintercalation within the KNVO nanobelts. The 3D-printed KNVO/rGO microlattice aerogel electrode has a high discharge capacity of 109.3 mAh g with a capacity retention rate of 92.6% after 200 cycles at 50 mA g and maintains a discharge capacity of 75.8 mAh g after 2000 cycles at 500 mA g. The flexible pouch-type KIB battery consisting of the 3D-printed KNVO/rGO has good mechanical durability and retains a high specific capacity under different forms of deformation such as bending and folding. The results provide valuable insights into the integration of advanced 3D-printed electrode materials into K-ion batteries and the design of flexible and wearable energy storage devices.
一种3D打印的富含氧空位的钒酸钾铵/还原氧化石墨烯（KNVO/rGO）微晶格气凝胶被设计用于高性能钾离子电池（KIBs）的阴极。具有周期性亚毫米微通道和相互连接的打印细丝的3D打印KNVO/rGO电极由高度分散的KNVO纳米带、褶皱的石墨烯纳米片和大量微孔组成。rGO骨架定义明确的3D多孔微晶格结构不仅提供了相互连接的导电3D网络和所需的机械强度，还促进了液体电解质渗透到内部活性位点，从而确保了KNVO纳米带内钾离子嵌入/脱出的稳定电化学环境。3D打印的KNVO/rGO微晶格气凝胶电极在50 mA g下循环200次后具有109.3 mAh g的高放电容量，容量保持率为92.6%，在500 mA g下循环2000次后仍保持75.8 mAh g的放电容量。由3D打印的KNVO/rGO组成的柔性软包型KIB电池具有良好的机械耐久性，在弯曲和折叠等不同形式的变形下仍保持高比容量。这些结果为将先进的3D打印电极材料集成到钾离子电池以及柔性和可穿戴储能设备的设计提供了有价值的见解。
