LAUSR

Abstract Graphene quantum dot (GQD) and carbon quantum dot (CQD) nanoparticles were employed to fabricate the crab-like GQD/poly(3-hexylthiophene) (P3HT) and semicrab-like CQD/P3HT short chain, pellet-like GQD/P3HT and CQD/P3HT long chain, GQD/P3HT nanofiber and CQD/P3HT nanofiber supramolecules. The P3HT crystals were composed of face-on ((1 0 0) and (0 0 2) prisms) and edge-on ((0 2 0) and (0 0 2) growth planes) oriented chains. The lowest d-spacing values were acquired for the QD decorated P3HT nanofibers (d(1 0 0) = 13.41–13.46 Ǻ and d(0 2 0) = 3.39–3.43 Ǻ). To investigate the function of designed supramolecules in roles of morphology modifier, donor, and acceptor, the ternary and binary photovoltaics of P3HT: ( Meissner and Wohrle, 1991 , Meissner and Wohrle, 1991 )-Phenyl C71 butyric acid methyl ester (PC71BM):supramolecule, P3HT:supramolecule, and PC71BM:supramolecule were prepared. The GQD-based nanostructures acted better than the CQD-based ones, originated from their thinner and disk-like nature, and the highest photovoltaic characteristics were detected in P3HT:PC71BM:GQD/P3HT nanofiber systems (14.06 mA cm−2, 0.70 V, 66.11%), leading to a performance of 6.50%. Thin films modified by crab-like GQD/P3HT short chain (5.47%), CQD/P3HT nanofiber (4.56%), and semicrab-like CQD/P3HT short chain (3.46%) nanostructures also reflected the high-quality devices. The systems manipulated by the crab/semicrab-like (668 and 462 Ω.cm2) and decorated fibrillar (553 and 395 Ω.cm2) nanostructures demonstrated the faster electron transport and, thereby the lower carrier recombination. Even the well-designed supramolecules of GQD/P3HT nanofiber and crab-like GQD/P3HT short chain led to the low-quality binary photovoltaics (3.68% and 2.29%) with respect to corresponding ternary systems. When the QDs and their associated nano-hybrids were employed as the electron donors, the weakest cells were fabricated and the highest efficacy was 2.01% for PC71BM:GQD/P3HT.