Fast and reproducible production of graphene flaks from graphite is an important process considering the possible industrial applications of graphene. We propose an electrochemical method to produce functionalized few-layer graphenes in minutes, without the need of prolonged ultrasonic treatment. It mainly consists in the cathodic electrochemical expansion of graphite in DMF. Functionalization of graphite is achieved by reducing aryl diazonium salts in organic solution. This simple methodology allows easily and quickly preparation of modified few-layer graphenes. Two different graphite sources were considered in this work for electrochemical graphene flaks production. (C) 2015 Elsevier B.V. All rights reserved.