▎ 摘　　要

Thermal management materials with high thermal conductivities, heat resistances, and excellent mechanical properties are urgently required for application in modern electronic power systems. The mechanical properties and high-temperature resistance of thermally conductive materials can be improved by using aramid nanofibers as thermally conductive substrates. In this study, para-aramid nanofibers (ANFs) were synthesized using a greener, time-efficient, and high-yield bottom-up method. Water-dispersible reduced graphene oxide (rGO) was combined with the ANFs to prepare a highly thermally conductive composite membrane with nacre-like struc-tures by vacuum filtration. The rGO-50/ANF showed a remarkably high thermal conductivity (18.28 W m-1 K-1) and excellent tensile strength (60.2 MPa) with a strong penchant for high-temperature applications (>200 degrees C). In particular, the composite film can significantly reduce the surface temperature of light-emitting diode lamps in practical thermal management applications, indicating its excellent thermal management performance.