Birch Reduction of Graphite. Edge and Interior Functionalization by Hydrogen

The Birch reduction (lithium in liquid ammonia) of, graphite,gives, a highly reduced, exfoliated product that is free of lithium. Edge and interior hydrogenation were demonstrated by solid-state C-13 NMR. spectroscopy. Elemental analysis of a carefully purified sample allows the chemical composition to be expressed as (C13H)(n). Atomic force microscopy images showed that the reduced graphene was highly exfoliated Hydrogen mapping by electron energy loss spectroscopy showed that the entire surface of reduced sample was covered by hydrogen, consistent with the NMR studies also indicating that hydrogen was added in interior positions of the graphene lattice as well as along the edge. A large band gap (4 eV) further establishes the high level of hydrogenation.