Assembly of Poly(3-hexylthiophene)/CdSe Hybrid Nanowires by Cocrystallization

A new approach to simultaneously organize crystalline n- and p-type materials into hybrid inorganic/organic nanowires was described. Solution crystallization of poly-(3-hexylthiophene) (P3HT) to form nanowires was induced by adding a poor solvent, CH2Cl2, to a solution of P3HT in CHCl3 to yield a final polymer concentration of 0.75 or 1.1 mg/mL. The graft density of P3HT ligands on the nanorods, estimated thermogravimetrically, is found to be substantially below the density of chains within a crystalline fibril, providing a viable mechanism for interpenetration of grafted chains into the P3HT fibrils. The orientations between rod and fibril axes are not consistent with a single Gaussian distribution about 0°, instead suggesting a secondary preferred orientation near 35°. The nanowires grow into stable structures over a 1-2 day period and remain suspended with no significant structural changes for at least many months.