National Academy of Sciences, Proceedings of the National Academy of Sciences, 33(117), p. 19685-19693, 2020
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Significance We demonstrate that engineering of two-dimensional molybdenum carbide/disulfide heterostructures can result in superconducting architectures with higher critical temperatures than that of pristine α-Mo 2 C. We developed a gas-phase reaction approach for the heterostack formation via phase transitions, which involves short sulfurization times (1–5 min) of α-Mo 2 C films. Heterostructures of α-Mo 2 C and γ′-phase MoC 1−x exhibit superconductivity with a higher critical temperature ( T C ∼ 6.8 K) than the original Mo 2 C crystal ( T C ∼ 4.0 K). The distinct chemical composition and modified structure of the metastable γ′-MoC 1−x phase present in the layered structure might lead to a higher interfacial density of states and increase in the frequency of the relevant phonon modes, thus contributing to the superconductivity and hence to a higher T C .