Evaluation of the electronic properties of perfluorophenyl functionalized quinolines and their hybrids with carbon nanostructures

Abstract

Hybrid materials based on perfluorophenyl functionalized quinolines directly attached onto the sp(2) hybridized surface of carbon nanostructures have been prepared and studied herein along with their precursor semiconducting small molecules. Tails of different polarities have been used so that the molecules would present improved solubility and controllable affinity for the selected substrates. These materials were evaluated for their electronic and electrochemical properties for potential application in organic photovoltaic solar cells (OPVs), using UPS, XPS and CV measurements after deposition onto oxygen plasma cleaned Si wafers or solvent treated ITO coated glass. A weak interaction between the fluorine atoms and both the Si and the ITO substrates was observed by XPS. The extent of this interfacial interaction was found to be related to the orientation of the quinoline moieties on the organic layer. Moreover, the combination of XPS and UPS analyses showed that the absolute energy value of the HOMO level increased as the amount of surface fluorine atoms increased. CV measurements revealed that hybridisation of the small molecules with carbon nanostructures decreases the materials' energy gap and increases the absolute energy value of the LUMO level. These features prove the efficiency of the proposed method to produce materials with controlled energy levels for solar cell devices.

Solution-phase molecular recognition of an azafullerene-quinoline dyad by a face-to-face porphyrin-dimer tweezer

“…In previous studies, analogous covalent dyads consisting of FQ and the C 60 fullerene have been successfully integrated in organic solar cells as electron acceptors utilizing poly-(3-hexyl thiophene) (P3HT), a widely adopted electron donor polymer with similar to (H 2 P) 2 tweezer HOMO-LUMO energy levels, as electron donor. 36 We rstly explore the complexation dynamics between C 59 N-FQ and (H 2 P) 2 tweezer by UV-Vis electronic absorption, steadystate and time-resolved uorescence emission spectroscopy. As depicted in Fig.…”

“…Moreover, the presence of the halogen atoms enabled their straightforward transformation to azides, allowing the direct incorporation on the sp 2 skeleton of carbon nanostructures via cycloaddition reactions. [35][36][37] More specic, (tetrauoro)azidophenyl-quinolines have been employed for the functionalization of carbon nanotubes, 35,36 C 60 (ref. 36 and 37) and phenyl-C 61 -butyric acid methyl ester (PCBM).…”

Synthesis of Polythiophene–Fullerene Hybrid Additives as Potential Compatibilizers of BHJ Active Layers

“…Moreover, in most such cases, a non-conjugated linkage between the semiconducting polymer and the carbon nanostructure has been employed preventing electronic interactions among the polymeric and fullerene parts of the hybrid materials. To overcome the above bottlenecks, new synthetic strategies involving the “direct” attachment of the two components, organic and fullerene ones, comprising the hybrid materials have been developed [49,50,51,52,53,54]. Working in this direction, we have recently reported a straightforward methodology for the development of hybrid semiconducting polymeric materials using the electron deficient perfluorophenyl functionality inserted either onto copolymeric materials or as end polymeric chain group [49,54].…”

“…Working in this direction, we have recently reported a straightforward methodology for the development of hybrid semiconducting polymeric materials using the electron deficient perfluorophenyl functionality inserted either onto copolymeric materials or as end polymeric chain group [49,54]. Benefits of this methodology are the direct electronic interactions between the two components [50], the absence of extra aliphatic or other non-conjugated parts used as connection bridges which increase the volume of insulating material within the active layer as well as the use of the intermediate perfluorophenyl aromatic azides that are stable over time and ambient storage conditions.…”

Semiconducting end-perfluorinated P3HT–fullerenic hybrids as potential additives for P3HT/IC70BA blends

“…Various synthetic strategies have been exploited for the preparation of such hybrid polymeric architectures, mostly employing multi-step synthetic procedures as well as the introduction of non-conjugated connecting bridges between the semiconducting polymer and the carbon nanostructure. Recently developed new synthetic approaches instead utilise the "direct" attachment of the semiconductor to the fullerene cage via diamino-, 39 cyclopentadienyl-, 40 or aziridine- 41,42,43 functional groups resulting in nearly fully conjugated systems. In this work, we focus on the development of such hybrid polymeric materials based on a previously reported methodology.…”