  Graphene nanosheets (GNS) paper is widely regarded as a promising candidate
for heat dissipation due to its outstanding thermal conductivity. However, the
accompanied high electrical conductivity makes it unfavorable for thermal
management of high power electronics since it runs a high risk of short
circuits. To eliminate the risk from the high electrical conductivity and
simultaneously maintain the excellent thermal performance, we introduce boron
nitride nanosheets (BNNS) that possess high thermal conductivity but electrical
insulation into the GNS paper. The hybrid paper has a much lower electrical
conductivity but similar thermal performance compared to the pristine GNS
paper. Besides, the flexible hybrid paper exhibits better thermal stability
than pure GNS paper. Our results show that the ability of BNNS to change the
electrical conductivity of paper without affecting its thermal conductivity is
potential for the application of heat management materials with tailored
electrical properties.
