▎ 摘　　要

Reduced graphene oxide (rGO) is an attractive material for heat dissipation films due to its high thermal conductivity. However, stacked rGO nanosheets generally suffer from low cross-plane thermal conductivity owing to inter-sheet gaps, which is an obstacle for implementing effective heat dissipation films. To resolve this issue, here, we propose multilayered films consisting of GO nanosheets and alumina nanoparticles using a spin-assisted layer-by-layer deposition method. Charged moiety-supplemented alumina nanoparticles are uniformly inserted between horizontally oriented GO nanosheets to compensate for the mitigated thermal transport encountered in GO-only stacked films. By virtue of successful electrostatic binding between GO nanosheets and functionalized alumina nanoparticles, alternately stacked films are readily grown up to similar to 10 mu m in thickness. After thermal reduction treatment, in particular, thermally non-conductive residual functional groups are completely removed while securing the structural intactness in layered stacking, and rGO/alumina stacked films exhibit a remarkably high in-plane thermal conductivity of 565 W m(-1) K-1, which is even greater than that of Cu films by a factor of 1.4. In particular, due to the formation of a well-interconnected, ladder-like architecture of alumina nanoparticles between rGO nanosheets, the assembled film exhibits a cross-plane thermal conductivity of 18.1 W m(-1) K-1, which outperforms rGO-stacked layers by two orders of magnitude. As a result, rGO/alumina films can show efficient heat dissipation performances by significantly reducing the maximum operating temperature of high-power light-emitting devices.