Dispersions and films comprising conducting polymer for optoelectronic devices

A dispersion, and a film and optoelectronic devices formed from the dispersion are provided. The dispersion comprising conducting polymer containing particles having a particle size of less than 450 nm, wherein the conducting polymer comprises substituted or unsubstituted, uncharged or charged polymerized units of thienoÄ3,4-bÜthiophene, and wherein a film drop cast from the dispersion has a conductivity from 10 to 10 S/cm measured using the four point probe method.