Catalytic activity of several graphene- and diamond-based carbon nanomaterials was compared in the reaction of the 1,2-dichloroethane (DCE) conversion using the impulse microcatalytic method. Only nanodiamonds and Ni-doped nanodiamonds were active in the reaction. A comparison of XRD, XPS, DRIFTS, and BET studies suggested that nitrogen or oxygen-containing groups could be responsible for the catalytic activity in the DCE reaction. However, nitrogen-doped carbon nanoflakes, which contain much more nitrogen-containing groups, showed no activity in the DCE conversion; hence, it is unlikely that nitrogen-containing groups of nanodiamond surface are active centers in DCE conversion. The role of oxygen-containing groups was studied in a test reaction of 2-propanol dehydrogenation/dehydration both nanotubes and nanodiamonds were active in the reaction; however, no activity of carbon nanotubes in the DCE conversion suggests that oxygen-containing groups are not active in the DCE conversion. As a result, we suggest that the carbon surface of nanodiamonds might be catalytically active in the DCE reaction. (C) 2015 Elsevier B.V. All rights reserved.