Li Xiaoyan, Deng Ransha, Li Qingping, Lin Dunmin, Wei Xijun, Liu Xiaoqin, Jiang Na, Huo Yu, Xie Fengyu, Zheng Qiaoji
College of Chemistry and Materials Science, Sichuan Normal University, Chengdu 610066, P. R. China.
State Key Laboratory of Environment-Friendly Energy Materials, School of Materials Science and Engineering, Southwest University of Science and Technology, Mianyang, Sichuan 621010, P. R. China.
Inorg Chem. 2021 Aug 2;60(15):11693-11702. doi: 10.1021/acs.inorgchem.1c01807. Epub 2021 Jul 15.
Transition-metal selenides have been considered as one of the most promising anode materials for sodium-ion batteries (SIBs) due to their high theoretical capacity and excellent rate performance. However, rapid capacity decay and poor cycling stability limit their practical application as the anode for SIBs. Carbon coating is one of the most effective ways to solve the above problems, but the thickness and uniformity of the coating layer are difficult to control. Herein, we successfully synthesize metal-organic framework (MOF)-derived porous N-doped carbon nanocubes homogeneously filled with ZnSe and CoSe and interconnected by reduced graphene oxide (ZCS@NC@rGO). ZCS@NC@rGO with more active sites and the synergistic effect of the ZnSe and CoSe heterojunction can enhance the sodium storage performance. The porous carbon nanocubes effectively prevent the agglomeration of active particles, and the rGO acting as a carbon network can significantly buffer the inevitable volume changes. At the same time, carbon nanocubes and the rGO are interconnecting to form a conductive network to accelerate electron transfer. Based on the aforementioned advantages, the ZCS@NC@rGO electrode shows an excellent sodium storage performance. Our investigation opens up a new horizon for the rational design of transition-metal selenide anodes for SIBs with a unique structure.
过渡金属硒化物因其高理论容量和优异的倍率性能，被认为是钠离子电池（SIBs）最有前景的负极材料之一。然而，快速的容量衰减和较差的循环稳定性限制了它们作为SIBs负极的实际应用。碳包覆是解决上述问题最有效的方法之一，但包覆层的厚度和均匀性难以控制。在此，我们成功合成了由金属有机框架（MOF）衍生的多孔氮掺杂碳纳米立方体，其均匀填充有ZnSe和CoSe，并通过还原氧化石墨烯相互连接（ZCS@NC@rGO）。具有更多活性位点以及ZnSe和CoSe异质结协同效应的ZCS@NC@rGO能够提升储钠性能。多孔碳纳米立方体有效防止了活性颗粒的团聚，而作为碳网络的rGO能够显著缓冲不可避免的体积变化。同时，碳纳米立方体与rGO相互连接形成导电网络以加速电子转移。基于上述优点，ZCS@NC@rGO电极展现出优异的储钠性能。我们的研究为合理设计具有独特结构的SIBs过渡金属硒化物负极开辟了新视野。
