The
extremely high thermal conductivity of graphene has received
great attention both in experiments and calculations. Obviously, new
features in thermal properties are of primary importance for application
of graphene-based materials in thermal management in nanoscale. Here,
we studied the thermal conductivity of graphene helicoid, a newly
reported graphene-related nanostructure, using molecular dynamics
simulation. Interestingly, in contrast to the converged cross-plane
thermal conductivity in multilayer graphene, axial thermal conductivity
of graphene helicoid keeps increasing with thickness with a power
law scaling relationship, which is a consequence of the divergent
in-plane thermal conductivity of two-dimensional graphene. Moreover,
the large overlap between adjacent layers in graphene helicoid also
promotes higher thermal conductivity than multilayer graphene. Furthermore,
in the small strain regime (<10%), compressive strain can effectively
increase the thermal conductivity of graphene helicoid, while in the
ultra large strain regime (∼100% to 500%), tensile strain does
not decrease the heat current, unlike that in generic solid-state
materials. Our results reveal that the divergence in thermal conductivity,
associated with the anomalous strain dependence and the unique structural
flexibility, makes graphene helicoid a new platform for studying fascinating
phenomena of key relevance to the scientific understanding and technological
applications of graphene-related materials
