A process and system for the electrochemical production of graphene, graphene oxide, graphene quantum dots, graphene/graphene oxide metal composites, graphene/graphene oxide coated substrates and graphene/graphene oxide metal composite coated substrates in a single step process involving no secondary purifications utilizes an electrochemical cell containing electrodes with variable gaps including a zero gap, containing an anode electrode including graphite, a cathode electrode including electrically conductive material with an electrolyte-free electrochemical bath including water and an organic liquid that produces joule heating along with oxygen embrittlement.