Synthesis and chemistry of metallo poly(phenylene diacetylenes)

We describe the synthesis and characterization of metallopolymers comprising poly(phenylene diacetylenes) containing platinum and cobalt species coordinated to the triple bonds of the diacetylene moities. Thermal treatment of these polymers as thin films results in their conversion to hetero glassy carbon (HGC). The coordinated metals are retained within the matrices of the glassy carbons as small metallic clusters (∼10‐30 Å for Pt and 50‐1000 Å for cobalt). The platinum doped glassy carbon shows remarkable activity for the reduction of both H⁺ and O₂, a result that has important implications for the development of fuel cell electrodes. At both pH 0 and 7, the platinum Pt‐HGC reduced the overpotential for O₂ reduction by ∼800 mV, and resulted in a voltammetric response similar to that of pure platinum.