  The van der Waals (vdW) interactions exist in reality universally and play an
important role in physics. Here, we show the study on the mechanism of vdW
interactions on phonon transport in atomic scale, which would boost
developments in heat management and energy conversion. Commonly, the vdW
interactions are regarded as a hindrance in phonon transport. Here, we propose
that the vdW confinement will enhance phonon transport. Through molecular
dynamics simulations, it shows that the vdW confinement makes more than
two-fold enhancement on thermal conductivity of both polyethylene single chain
and graphene nanoribbon. The quantitative analyses of morphology, local vdW
potential energy and dynamical properties are carried out to reveal the
underlying physical mechanism. It is found that the confined vdW potential
barriers reduce the atomic thermal displacement magnitudes, thus lead to less
phonon scattering and facilitate thermal transport. Our study offers a new
strategy to modulate the heat transport.
