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Electrochemiluminescence of corannulene in acetonitrile by the use of coreactants is reported here for the first time. The investigation has been carried out utilizing both benzoyl peroxide as a sacrificial coreactant and arylamine derivatives as nonsacrificial species to perform mixed-annihilation processes. The electrochemiluminescence produces an intense blue light. The use of different tris(arylamines) as mixed-annihilation coreactants gives rise to exciplexes with corannulene that emit at different wavelengths, thus allowing the emission color to be tuned by changing the coreactant molecule. This opens a potential pathway to exploitation of such an intriguing carbon structure for building efficient blue-light emitting devices.

The voltammetric generation of corannulene anions was investigated over a large range of experimental conditions comprising either "traditional" electrochemical solvents, such as dimethylformamide, acetonitrile, and tetrahydrofuran, or "unconventional" solvents, such as liquid ammonia, liquid methylamine, or liquid dimethylamine, and several different supporting electrolytes. Strong ion pairing effects were found to dominate the electrochemical generation of corannulene higher anions, and through the suitable choice of the solvent/electrolyte system, we observed, for the first time, the reversible electrochemical generation of up to the triply reduced corannulene. The standard potentials obtained experimentally compared rather well with the theoretical values calculated by ab initio and density functional methods, in which solvation and ion pairing effect were explicitly taken into account. In particular, the calculations considered the effect of the electrolyte cation size on ion pairing in order to rationalize the occurrence of the third reduction within the experimental potential window.