In catalytic reactions in lithium-sulfur batteries, defects are generally considered to be efficient and flexible. However, the effect of defect concentrations on catalysis remains unclear.
Fig.1 Theoretical simulation
Shao Huaiyu of the University of Macau, Raven of Wuhan University of Science and TechnologyThe quantitative relationship between defect concentration and adsorption catalytic performance was studied by using MOS2 with different defect levels as a model. Specifically, this work investigated the catalytic mechanism of sulfur-containing vacant MOS2 through density functional theory (DFT) and in-situ experiments.
It is found that with the increase of sulfur defects, the electronic structure and geometry of MOS2 have undergone significant changes, which has an important impact on the regulation of the catalytic reaction of lithium-sulfur batteries.
Fig.2 Adsorption and catalysis of LIPS by different catalysts
Only an optimal defect concentration can achieve the equilibrium between adsorption and desorption of Lipss, resulting in accelerated redox kinetics and optimal electrochemical performance. Increasing the defect content in turn disrupts the geometry of the material, making it difficult to desorb the LIPS and slowing the transformation. The trends revealed in this work broaden the field of defect design and can be applied to other areas of catalysis and beyond, providing a potential approach for the commercialization of lithium-sulfur batteries.
Fig.3 Performance of lithium-sulfur batteries based on different catalysts
elucidating the volcanic-type catalytic beh**ior in lithium–sulfur batteries via defect engineering. acs nano 2023. doi: 10.1021/acsnano.3c05269