TECHNOLOGY FOCUS - ELECTRONICS - Preferred Device: The device further comprises an electron-transporting or hole-blocking layer intermediate the photovoltaic layer and the electron-collecting electrode. The device further comprises a hole-transporting layer intermediate the photovoltaic layer and the hole-collecting electrode; and a substrate.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Components: The acceptor compound is selected from (6,6)-phenyl-61C butyric acid methyl ester, (6,6)-phenyl-71C butyric acid methyl ester, and (6,6)-phenyl-85C butyric acid methyl ester.    TECHNOLOGY FOCUS - POLYMERS - Preferred Method: The mixture of the at least one acceptor compounds and the at least one nanowires is prepared by combining a first solution comprising the at least one acceptor compounds in a first solvent with a suspension of the at least one nanowires in a second solvent. The mixture of the at least one acceptor compounds and the at least one nanowires is prepared by combining a first solution comprising the at least one acceptor compounds in a first solvent with second solution comprising at least one poly(3-alkylthiophene)s in a second solvent. The method (m2) further involves thermal annealing the composite. The method (m4) further involves forming a hole-transporting layer; and forming an electron-transporting layer. Preferred Components: The acceptor compound is selected from a fullerene or fullerene derivative, an inorganic nanocrystal, and a semiconducting nanoparticle. The poly(3-alkylthiophene) nanowire comprises a poly(3-alkylthiophene) selected from poly(3-methylthiophene), poly(3-ethylthiophene), poly(3-propylthiophene), poly(3-butylthiophene), poly(3-pentylthiophene), poly(3-hexylthiophene), poly(3-heptylthiophene), poly(3-octylthiophene), poly(3-nonylthiophene) and/or poly(3-decylthiophene). Preferred Composite: The ratio of poly(3-alkylthiophene) nanowire to acceptor compound is 1:0.2-1:5 (weight ratio).The composite has a thickness of 30-500 nm. EXAMPLE - Nitrogen-degassed 1,2-dichlorobenzene (ODCB) solvent (5 ml) was added to a 10 ml bottle containing poly(3-butylthiophene) (P3BT) sample (30 mg); the suspension (6 mg/ml) was stirred for 24 hour at 90-100 degrees C until P3BT was completely dissolved. The hot solution was filtered through a 0.45 mu m filter and the filtrate was put in a dark environment for 72 hour to allow P3BT molecules to self-assemble. The original orange brown color of the solution changed to dark violet after the P3BT nanowires (P3BT-nw) were formed as a dispersion. The P3BT nanowire suspension was found to be quite stable. The nanowires did not dissolve in nitrogen-degassed 1,2-dichlorobenzene (ODCB) by dilution and did not precipitate in over one month of standing.