Constructing Heterointerface of Metal Atomic Layer and Amorphous Anode Material for High-Capacity and Fast Lithium Storage

Development of efficient lithium-ion batteries is highly promising power source for future generation energy applications. This can be attributed to their efficiency and portability. Currently, graphite has been mainly used as anode materials in lithium-ion batteries. Unfortunately, graphite-based anodes have low lithium storage capacity which compromises the performance of lithium-ion batteries. As such, researchers have been looking for alternatives and have identified amorphous anode material as a promising solution.

Presently, enhancing the performances of anodic materials have been a major focus. Other than interfacial engineering, other methods have also been developed to increase lithium storage capacities. However, discrete distribution on the anode material surface during particles deposition has resulted in unstable lithiation and delithiation processes. Therefore, effective methods for achieving the uniform metal layer on the anode materials is highly desirable. In a recently published literature, ternary metal oxides with different metal cations exhibited excellent structural stability, reversible capacity, and theoretical capacity thus promising anodic materials for lithium-ion batteries. However, their low electron diffusion rate leading to unstable lithiation and delithiation which have not been fully explored.

To this note, scientists led by Professor Jinhu Yang at Tongji University designed and constructed amorphous porous CoSnO₃ nanocubes for high-performance anodic material. The design was based on the Au atomic cluster layer-terminated heterointerface that was constructed using the galvanic replacement reaction method. They further investigated the advantages of using the CoSnO₃/ Au composites in terms of structural composition, electrical conductivity, reversibility, and lithium diffusion rate. Their research work is currently published in the research journal, ACS Nano.

In brief, the research team initiated their studies by exploring interfacial engineering as a method for optimizing the electrode materials properties suitable for energy applications. Additionally, for the lithium-ion batteries investigated here, a galvanic replacement method was used to fabricate the amorphous porous CoSnO₃ nanocubes. Eventually, they used density functional theory calculations to investigate the lithium storage mechanism at the CoSnO₃//Au heterointerface.

The authors observed that the fabricated amorphous anode material exhibited high reversible capacity, good rate capability as well as good cycling stability. In addition, the performance of the lithium-ion batteries was significantly enhanced. The high lithium ion batteries performance was attributed to the amorphous nature of the CoSnO₃ //Au heterointerface. Furthermore, it was worth noting that the amorphous nature was also the reason for the improved ion diffusion, electron transport as well as minimizing the volume strain.

In summary, Ting He (PhD candidate) and her colleagues successfully constructed CoSnO₃ //Au heterointerface for fast and high capacity lithium storage. To actualize their study, it was necessary to perform density functional theory calculations. An enhanced theoretical lithium storage capacity was obtained due to the initiated atomic polarization and reduced lithium ion diffusion barriers. Altogether, the study pioneers the use of amorphous materials to realize high-performance lithium-ion batteries which will be of great significance for future energy advancement.