We report here the synthesis and grafting of easily accessible catechol-terminated poly(3-hexylthiophenes) onto Al-doped ZnO particles (ZnO:Al) to obtain a performance-improved polycrystalline assembly. These macromolecular binding species favor electronic conduction from one grain to another. Resistivity measurements of the grafted ZnO:Al powders performed under compression show an increased conductivity as compared to the pure ZnO:Al powders. The catechol function terminating the polymer appears to play an important role on its effect by forming a strong covalent bond with the surface of the zinc oxide. In particular, the conductivity obtained under characteristic pressures of lamination processes gives 1-10 Omega cm, evidencing the great potential of such an approach for preparation of flexible or thermoreactive films.