Scaling up Simultaneous Exfoliation and 2H to 1T Phase Transformation of MoS₂

Abstract

Large‐scale production of high‐quality ultrathin layers (1–3 nm) of molybdenum disulfide (MoS2) with absolute (≈100%) 1T‐phase is still in its infancy. Therefore, it is extremely crucial to have a technique for the mass production of ultrathin 1T‐MoS2 layers. Here, a direct, single‐step, and ultra‐fast technique that produces high‐quality ultrathin layers of 1T‐MoS2 with a production rate as high as 58 g h−1 without the usage of any intercalates or solvents is demonstrated. The exfoliated ultrathin 1T‐MoS2 layers exhibited ≈100% 1T‐phase with a large specific surface area (67 m2 g−1), higher electrical conductivity (140 S m−1), high thermal stability (up to 500 °C) and hydrophilicity (water contact angle (WCA): ≈23.4⁰). The ultrathin 1T‐MoS2 layers showed a higher specific capacitance of 420 F g−1; perhaps an ideal candidate for the electrodes of supercapacitors. Moreover, the ultrathin 1T‐MoS2 layer exhibited better mechanical flexibility and retained its original performance on bending between 0 and 180⁰ angles. Further, to assess the adeptness of the protocol, An initial trial is done on other transition metal dichalcogenides (TMDs) i.e., tungsten disulfide (WS2), and observe similar results. The work sheds light on the simultaneous exfoliation and phase transformation of TMDs in large quantities, and detailed proofs‐of‐concept demonstrate its application in next‐generation energy storage devices.