ELECTROCHEMICAL GENERATION OF NARROW CONDUCTION ELECTRON-SPIN-RESONANCE SIGNALS IN CARBON-BLACKS

Electrochemical reduction of either of two different carbon blacks dispersed in methylene chloride gave rise to a temperature independent narrow ESR signal superimposed upon the characteristic broad signal. The observation of this conduction ESR (CESR) signal implies that there are two distinct environments available for charge carriers within the carbon black particles. With the oxidized black, an additional ESR spectrum (g equals 2. 0034) revealing hyperfine interaction was observed. This was associated with surface oxidized molecules which had been electrochemically reduced and reside in solution as radical anions.