High-Entropy 1T-Phase Quantum Sheets of Transition-Metal Disulfides

Quantum sheets of transition-metal dichalcogenides (TMDs) are promising nanomaterials owing to the combination of both 2D nanosheets and quantum dots with distinctive properties. However, the quantum sheets usually possess semiconducting behavior associated with 2H phase, it remains challenging to produce 1T-phase quantum sheets due to the easy sliding of the basal plane susceptible to the small lateral sizes. Here, an efficient high-entropy strategy is developed to produce 1T-phase quantum sheets of transition-metal disulfides based on controllable introduction of multiple metal atoms with large size differences to retard the sliding of basal plane. The key is the topological conversion of in-plane ordered carbide laminates (i-MAX) compatible with multiple atoms to high-entropy transition-metal disulfides with high strains and 1T phase, which facilely triggers the fracture into 1T-phase quantum sheets with average size of 4.5 nm and thickness of 0.7 nm during the exfoliation process. Thus, the 1T-phase disulfide quantum sheets show high electrocatalytic activities for lithium polysulfides, achieving a good rate performance of 744 mAh g^-1 at 5 C and a long cycle stability in lithium-sulfur batteries.