Surface charge transfer doping (SCTD) preserves the pristine crystal structure and allows precise tuning of the doping level, making it a promising strategy for modulating the properties of low-dimensional materials. In this work, we investigate the effect of surface ${\mathrm{MoO}}_3$ molecular doping on the thermal transport properties of monolayer ${\mathrm{MoS}}_2$. Density functional theory calculations reveal that surface-adsorbed ${\mathrm{MoO}}_3$ enables the injection of holes ($0.331\mathrm{e}{\mathrm{molecule}}^{-1}$) into monolayer ${\mathrm{MoS}}_2$, providing $p$-type doping. The charge transfer also leads to strong adsorption of the ${\mathrm{MoO}}_3$ molecule on the ${\mathrm{MoS}}_2$, with adsorption energies below –1.85 eV. Based on a developed neuroevolution potential and homogeneous nonequilibrium molecular dynamics simulations, we demonstrate that ${\mathrm{MoO}}_3$ adsorption significantly reduces the lattice thermal conductivity (LTC) of monolayer ${\mathrm{MoS}}_2$. At 300 K, the LTC decreases from $163.9\mathrm{W}{\mathrm{m}}^{-1}{\mathrm{K}}^{-1}$ in pristine ${\mathrm{MoS}}_2$ to $47.3\mathrm{W}{\mathrm{m}}^{-1}{\mathrm{K}}^{-1}$ at a doping level of $1.82\times {10}^{13}\mathrm{molecule}{\mathrm{cm}}^{-2}$. The LTC is further reduced to $28.3\mathrm{W}{\mathrm{m}}^{-1}{\mathrm{K}}^{-1}$ when the concentration of ${\mathrm{MoO}}_3$ increases to 7.29×${10}^{13}\mathrm{molecule}{\mathrm{cm}}^{-2}$. The introduction of surface ${\mathrm{MoO}}_3$ dopants generates resonant flat bands at various frequencies in the phonon dispersion curves. These resonant modes interact with propagating modes in ${\mathrm{MoS}}_2$, which not only reduce phonon group velocities but also enhance phonon–phonon scattering by increasing the number of scattering channels. The resonant effect is particularly pronounced in the low-frequency regime, where the phonon mean free path is reduced by more than one order of magnitude when the doping concentration exceeds 1.82×${10}^{13}\mathrm{molecule}{\mathrm{cm}}^{-2}$. This work demonstrates that SCTD not only enables efficient carrier modulation in 2D semiconductors but also provides precise control over thermal transport through the phonon resonance effect, offering a strategy for the design of high-performance 2D thermoelectric materials.

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• Machine learning models
• Phonons
• Thermal transport
• Transition metal dichalcogenides