Liao Mengchen, Zhang Kai, Luo Chaowei, Wu Guozhong, Zeng Hongyan
School of Chemistry and Chemical Engineering, Central South University, Changsha 410083, China.
Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China.
Materials (Basel). 2024 Aug 13;17(16):4030. doi: 10.3390/ma17164030.
Designing efficient electrode materials is necessary for supercapacitors but remains highly challenging. Herein, cobalt sulfide with crystalline/amorphous heterophase (denoted as Co(Al)S) derived from an Al metal-organic framework was constructed by ion exchange/acid etching and subsequent sulfidation strategy. It was found that rational sulfidation by adjusting the sulfur source concentration to a suitable level was favorable to form a 3D nanosheet-interconnected network architecture with a large specific surface area, which promoted ion/electron transport and charge separation. Benefiting from the features of the unique network structure and heterophase accompanied by aluminum, nitrogen and carbon coordinated in amorphous phase, the optimal Co(Al)S exhibited a high specific capacity (1791.8 C g at 1 A g), an outstanding rate capability and an excellent cycling stability. Furthermore, the as-assembled Co(Al)S//AC device afforded an energy density of 72.3 Wh kg at a power density of 750 W kg, verifying that the Co(Al)S was a promising material for energy storage devices. The developed scheme is expected to promote the application of MOF-derived electrode materials in electrochemical energy storage and conversion fields.
设计高效的电极材料对于超级电容器来说是必要的，但仍然极具挑战性。在此，通过离子交换/酸蚀刻及后续硫化策略构建了一种由铝基金属有机框架衍生而来的具有晶态/非晶态异相的硫化钴（记为Co(Al)S）。研究发现，通过将硫源浓度调节至合适水平进行合理硫化有利于形成具有大比表面积的三维纳米片互连网络结构，这促进了离子/电子传输和电荷分离。得益于独特网络结构以及非晶相中铝、氮和碳配位的异相特性，最优的Co(Al)S展现出高比容量（在1 A g下为1791.8 C g）、出色的倍率性能和优异的循环稳定性。此外，组装好的Co(Al)S//AC器件在功率密度为750 W kg时能量密度达到72.3 Wh kg，证实Co(Al)S是一种用于储能器件的有前景的材料。所开发的方案有望推动金属有机框架衍生电极材料在电化学储能和转换领域的应用。
