Carbonaceous Materials Derived from Polyparaphenylene Pyrolyzed at Low Temperature : Infrared and Raman Spectroscopies Characterisation

Polyparaphenylene, (C₆H₄)x or PPP, is a redox conducting polymer. When treated at 700°C, it can be electrochemically doped with lithium and exhibits lithium affinities which are much higher than those observed with graphite. Moreover, the different shapes of the electro intercalation curves obtained with graphite and with this pyrolyzed PPP suggest different mechanisms of lithium insertion: PPP thermally treated displays a large hysteresis in the galvanostatic curves contrary to graphite. In order to observe the evolution of the decomposition of PPP, we report infrared and Raman spectroscopy studies on this polymer treated at 700°C in argon atmosphere during increasing pyrolysis times.