  We synthesized three-dimensional nanoporous graphene films by a chemical
vapor deposition method with nanoporous copper as a catalytic substrate. The
resulting nanoporous graphene has the same average pore size as the underlying
copper substrate. Our surface-enhanced Raman scattering (SERS) investigation
indicates that the nanoporosity of graphene significantly improves the SERS
efficiency of graphene as a substrate as compared to planar graphene
substrates.
