The present invention is generally directed to internally functionalized graphene substrates, methods of making such substrates and methods of using such substrates. In one aspect, the present invention is a graphene substrate. The substrate comprises edge and non-edge regions. Organic or inorganic molecules are bound to the non-edge regions of the substrate, and the organic or inorganic molecules are present on the substrate edges at a population greater than about one molecule per 10,000 nm2.