Cyanographene and Graphene Acid: The Functional Group of Graphene Derivative Determines the Application in Electrochemical Sensing and Capacitors Yi Heng Cheong, Muhammad Zafir Mohamad Nasir, Aristides Bakandritsos, Martin Pykal, Petr Jakubec, Radek Zboril, Michal Otyepka, Martin Pumera* Chemelectrochem 2019, 6(1), 229-234