Superconductivity in bulk 2H-MoS₂ via carrier doping

As a prototypical transition metal dichalcogenide (TMD) semiconductor, MoS₂ exhibits diverse tunable electronic properties in low-dimensional systems, such as Ising superconductivity and charge density waves (CDWs). However, the intrinsic superconductivity of bulk MoS₂ remains underexplored. Here, we demonstrate carrier doping in bulk 2H-MoS₂ using an ionic-liquid-gating method, resulting in anisotropic bulk superconductivity with a critical temperature T_c of 3.2 K. Notably, the superconducting transition in the bulk requires the lowest critical carrier density (∼10¹³ cm⁻²) among all the reported superconducting MoS₂ systems, while exhibiting a higher T_c than typically observed in monolayers. The electron–phonon coupling (EPC) constant extracted from Raman spectroscopy yields a calculated T_c consistent with the experimental observations, in agreement with the mechanism established in monolayer MoS₂. We attribute these observations to the Fermi level preferentially crossing the lower-energy Q point in the bulk, which facilitates superconducting pairing. The results provide deeper insights into the superconducting mechanism in bulk 2H-MoS₂.