摘要
Monolayer molybdenum disulfide (MoS2) is one of the most studied two-dimensional materials. While the thermodynamically stable and well-investigated state of monolayer MoS2 is the semiconducting 1H phase, it can also exist in the 1T ' phase, which exhibits semimetallic characteristics and topologically protected properties. However, scalable postsynthetic methods to achieve and stabilize the 1T ' phase remain elusive, as monolayer MoS2 selectively reverts to the 1H phase under thermal equilibrium. In this study, we present a strategy to induce, stabilize, and spatially define the 1T ' phase in monolayer MoS2 synthesized via chemical vapor deposition (CVD). By employing a sequential oxidation process followed by polymer enwrapment, we successfully converted CVD-grown monolayer MoS2 from the 1H phase to the 1T ' phase. Transport measurements reveal a weak gate dependence, consistent with the semimetallic nature of the 1T ' phase. Our results further demonstrate that interfacial interactions with the polymer play a critical role in both facilitating the conversion and stabilization of the 1T ' monolayer MoS2. The phase conversion from 1H to 1T ' induces significant structural rearrangements, leading to the formation of nanoscale wrinkles in the monolayer flake. The lateral size of the 1T ' domains is estimated to be approximately 100-200 nm, suggesting that an in-plane strain of approximately 1% is introduced during the oxidation process. This strain is effectively stabilized by the polymer interface. The entire treatment is carried out under ambient conditions at room temperature, providing a simple and scalable approach to phase engineering in two-dimensional materials.