Electrochemistry combined with electrospray mass spectrometry has proven to be very effective for investigating electrochemical processes. Results of the electrochemical oxidation of CN- at platinum electrode in acetonitrile using the electrochemical/electrospray mass spectrometric method are reported. Two novel potential-dependent mass peaks are observed in the 3-dimension mass spectra. The mass peak at m/z 130 can be assigned to [C5N5](-), which has been previously postulated as the intermediate during the nucleophilic addition of cyanogen to cyanide. We observe another potential-dependent mass peak at m/z 156 which could represent [C6N6](center dot-), a trimer of cyanogen, or [C12N12](2-), the dimer of [C6N6](center dot-). Published by Elsevier B.V.