Deng Xiaoyang, Zhang Pengfei, Wan Zihao, Ma Zizai, Wang Xiaoguang
Laboratory of Advanced Materials and Energy Electrochemistry, Institute of New Carbon Materials, College of Materials Science and Engineering, Taiyuan University of Technology, Taiyuan, Shanxi, 030024, China.
Shanxi Key Laboratory of Gas Energy Efficient and Clean Utilization, Taiyuan, Shanxi, 030024, China.
Small. 2024 Aug;20(31):e2311332. doi: 10.1002/smll.202311332. Epub 2024 Mar 3.
Aqueous zinc-ion batteries (AZIBs) are considered a promising device for next-generation energy storage due to their high safety and low cost. However, developing high-performance cathodes that can be matched with zinc metal anodes remains a challenge in unlocking the full potential of AZIBs. In this study, a typical transition metal layered double hydroxides (NiCo-LDHs) can be in situ reconstructed to NiCo-LDHs/Ni(Co)OOH heterostructure using an electrochemical cycling activation (ECA) method, serving as a novel cathode material for AZIBs. The optimized ECA-NiCo-LDHs cathode demonstrates a high capacity of 181.5 mAh g at 1 A g and retains 75% of initial capacity after 700 cycles at 5 A g. The abundant heterointerfaces of the NiCo-LDHs/Ni(Co)OOH material can activate additional active sites for zinc-ion storage and accelerate ion diffusion. Theoretical calculations also suggest the heterostructure can boost charge transfer and regulate ion-adsorption capability, thereby improving the electrochemical performance. Additionally, the flexible AZIBs device exhibits good service performance. This study on interface engineering introduces a new possibility for utilizing LDHs in AZIBs and offers a novel strategy for designing electrode materials.
水系锌离子电池（AZIBs）因其高安全性和低成本，被认为是下一代储能的理想装置。然而，开发能与锌金属负极相匹配的高性能正极，仍是释放AZIBs全部潜力的一项挑战。在本研究中，一种典型的过渡金属层状双氢氧化物（NiCo-LDHs）可通过电化学循环活化（ECA）方法原位重构为NiCo-LDHs/Ni(Co)OOH异质结构，用作AZIBs的新型正极材料。优化后的ECA-NiCo-LDHs正极在1 A g电流密度下展现出181.5 mAh g的高容量，在5 A g电流密度下循环700次后仍保留75%的初始容量。NiCo-LDHs/Ni(Co)OOH材料丰富的异质界面可激活额外的锌离子存储活性位点并加速离子扩散。理论计算还表明，该异质结构可促进电荷转移并调节离子吸附能力，从而改善电化学性能。此外，柔性AZIBs器件表现出良好的使用性能。这项关于界面工程的研究为在AZIBs中利用LDHs引入了新的可能性，并为电极材料设计提供了一种新策略。
