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Exfoliated MoS₂ and MoSe₂ Nanosheets by a Supercritical Fluid Process for a Hybrid Mg-Li-Ion Battery.

ABSTRACT: The ultrathin two-dimensional nanosheets of layered transition-metal dichalcogenides (TMDs) have attracted great interest as an important class of materials for fundamental research and technological applications. Solution-phase processes are highly desirable to produce a large amount of TMD nanosheets for applications in energy conversion and energy storage such as catalysis, electronics, rechargeable batteries, and capacitors. Here, we report a rapid exfoliation by supercritical fluid processing for the production of MoS₂ and MoSe₂ nanosheets. Atomic-resolution high-angle annular dark-field imaging reveals high-quality exfoliated MoS₂ and MoSe₂ nanosheets with hexagonal structures, which retain their 2H stacking sequence. The obtained nanosheets were tested for their electrochemical performance in a hybrid Mg-Li-ion battery as a proof of functionality. The MoS₂ and MoSe₂ nanosheets exhibited the specific capacities of 81 and 55 mA h g^-1, respectively, at a current rate of 20 mA g^-1.

SUBMITTER: Truong QD

PROVIDER: S-EPMC6640930 | biostudies-literature |

REPOSITORIES: biostudies-literature

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