  In this study, we report a different strategy to prepare graphene nanopapers
from direct vacuum filtration. Instead of the conventional method, i.e. thermal
annealing nanopapers at extremely high temperatures prepared from graphene
oxide (GO) or partially reduced GO, we fabricate our graphene nanopapers
directly from suspensions of fully reduced graphene oxide (RGO), obtained after
RGO and thermally annealing at 1700 {\deg}C in vacuum. By using this approach,
we studied the effect of thermal annealing on the physical properties of the
macroscopic graphene-based papers. Indeed, we demonstrated that the enhancement
of the thermal and electrical properties of graphene nanopapers prepared from
annealed RGO is strongly influenced by the absence of oxygen functionalities
and the morphology of the nanoflakes. Hence, our methodology can be considered
as a valid alternative to the classical approach.
