Cheng Hao, Xu Huan, Shang Jian, Xu Yinan, Zong Haoming, Yao Wenjiao, Fang Zebo, Dou Weidong, Zhang Luojiang, Tang Yongbing
Department of Physics, Shaoxing University, 312000, Shaoxing, China.
Advanced Energy Storage Technology Research Center, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, 518055, Shenzhen, China.
Angew Chem Int Ed Engl. 2025 Jan 10;64(2):e202414302. doi: 10.1002/anie.202414302. Epub 2024 Nov 2.
Metal hexacyanoferrates (MHCFs) with adjustable composition and open framework structures have been considered as intriguing cathode materials for sodium-ion batteries (SIBs). Exploiting MHCFs with ultrafast and durable sodium storage capability as well as comparable capacity is always a goal that many investigators pursue, but remains challenging. Herein, simultaneous tailoring of chemical composition and morphology configuration is carried out to design a hollow monoclinic high-entropy MHCF (HMHE-HCF) assembled by nanocubes for the first time to realize the objective. The "cocktail effect" of high-entropy construction, rich sodium content of monoclinic phase, and unique hollow structure endow HMHE-HCF cathode with fast reaction kinetics and energetically stable performance during continuous charging/discharging processes. As a result, the HMHE-HCF cathode demonstrates superior rate performance up to an ultra-high rate of 100 C (71.1 % retention to 0.1 C), and remarkable cycling stability with a capacity retention of 77.8 % over 25,000 cycles at 100 C, outperforming most reported sodium-ion cathodes. Further, the HMHE-HCF//hard carbon full-cell delivers capacities of 99.0 and 82.3 mAh g at 0.1 C and 10 C, respectively, and retains 98.1 % of the initial capacity after 1,600 cycles at 5 C, demonstrating its potential application for sodium-ion storage.
具有可调节组成和开放框架结构的金属六氰合铁酸盐（MHCFs）被认为是钠离子电池（SIBs）中极具吸引力的阴极材料。开发具有超快且持久的钠存储能力以及可比容量的MHCFs一直是许多研究人员追求的目标，但仍然具有挑战性。在此，首次通过同时调整化学成分和形态构型来设计一种由纳米立方体组装而成的中空单斜高熵MHCF（HMHE-HCF），以实现这一目标。高熵结构的“鸡尾酒效应”、单斜相丰富的钠含量以及独特的中空结构，赋予了HMHE-HCF阴极在连续充电/放电过程中快速的反应动力学和能量稳定的性能。结果，HMHE-HCF阴极在高达100 C的超高倍率下表现出卓越的倍率性能（相对于0.1 C保留71.1%），并且在100 C下循环25,000次后具有77.8%的容量保持率，展现出出色的循环稳定性，优于大多数已报道的钠离子阴极。此外，HMHE-HCF//硬碳全电池在0.1 C和10 C时分别提供99.0和82.3 mAh g的容量，并且在5 C下循环1600次后保留了初始容量的98.1%，证明了其在钠离子存储方面的潜在应用。
