Liu Heng, Xiong Shuangsheng, Hou Li, Han Minze, Mao Yuezhen, Zhang Zhengguang, Zhao Zhibin, Gao Faming
Hebei Key Laboratory of Applied Chemistry, School of Environmental and Chemical Engineering, Yanshan University, Qinhuangdao 066004, China.
Hebei Key Laboratory of Applied Chemistry, School of Environmental and Chemical Engineering, Yanshan University, Qinhuangdao 066004, China.
J Colloid Interface Sci. 2023 Jan 15;630(Pt B):623-633. doi: 10.1016/j.jcis.2022.09.067. Epub 2022 Sep 16.
Constructing bimetallic sulfide components are considered to be a promising and efficient lithium storage materials. Nonetheless, preparation routes of rational structures that have abundant hierarchical interfaces or phase boundaries bimetallic sulfide are still a problem to over come. In this work, a novel hierarchical nanostructure of bimetal sulfide CoS-MoS nanorods are synthesized successfully by in-situ self-growth means at the hydrothermal conditions. Subsequently, we loaded it to the carbon matrix (CoS-MoS@rGO) forming a three-dimensional structures with the help of freeze drying technology. This well-designed hierarchical structure could created a stable heterogeneous contact surface, which guarantees rapid Li ions diffusion and facilitates charge transfer at the heterointerface. Which can maintain capacity of 776 mAh/g over 800 cycles at 1 A/g. On the other hand, it shows an excellent rate capability of 464 mAg h at 5 A/g. From the perspective of electrochemical kinetics, we analyze and explore the reason about the improved lithium storage performance. Furthermore, to insight into the relationship between matter and phase conversion, the in-situ X-ray diffraction characterization is executed. The strategy of rationally designing hierarchical heterostructures will shed light on outstanding electrochemical performance in energy storage applications.
构建双金属硫化物组件被认为是一种很有前景且高效的锂存储材料。然而，制备具有丰富分级界面或相界的双金属硫化物合理结构的途径仍然是一个有待克服的问题。在这项工作中，通过水热条件下的原位自生长方法成功合成了一种新型的双金属硫化物CoS-MoS纳米棒分级纳米结构。随后，我们借助冷冻干燥技术将其负载到碳基质（CoS-MoS@rGO）上，形成三维结构。这种精心设计的分级结构可以创建一个稳定的异质接触表面，保证锂离子快速扩散，并促进异质界面处的电荷转移。在1 A/g的电流密度下，经过800次循环后仍能保持776 mAh/g的容量。另一方面，在5 A/g的电流密度下，它表现出464 mAh/g的优异倍率性能。从电化学动力学的角度，我们分析并探究了锂存储性能提高的原因。此外，为了深入了解物质与相变之间的关系，进行了原位X射线衍射表征。合理设计分级异质结构的策略将为储能应用中的优异电化学性能提供启示。
