Considering the important role played by surface functionalities, we have obtained quantitative estimates of the functionalities on graphene, BN and borocarbonitrides, by employing fluorescence labeling. Thus, the surface concentrations of carbonyl, carboxylic and hydroxyl groups on the graphene surface are 2.31 x 10(20), 28.17 x 10(20) and 0.08 x 10(20) per gram respectively. We do not observe carbonyl groups on reduced graphene oxide. The surface concentration of the amine group on BN is 0.01 x 10(20) per gram. Borocarbonitrides contain amine and oxygen functionalities, with composition dependent concentrations. Supercapacitor performance and ORR activity of the borocarbonitrides are presented along with their surface areas. (C) 2017 Elsevier B.V. All rights reserved.