Design of Assembled Systems Based on Conjugated Polyphenylene Derivatives and Carbon Nanohorns

Abstract

Promising materials have been designed and fully characterised by an effective interaction between versatile platforms such as carbon nanohorns (CNHs) and conjugated molecules based on thiophene derivatives. Easy and non-aggressive methods have been described for the synthesis and purification of the final systems. Oligothiophenephenylvinylene (OTP) systems with different geometries and electron density are coupled to the CNHs. A wide range of characterization techniques have been used to confirm the effective interaction between the donor (OTP) and the acceptor (CNH) systems. These hybrid materials show potential for integration into solar cell devices. Importantly, surface-enhanced Raman spectroscopy (SERS) effects are observed without the presence of any metal surface in the system. Theoretical calculations have been performed to study the optimised geometries of the noncovalent interaction between the surface and the organic molecule. The calculations allow information on the monoelectronic energies of HOMO-LUMO orbitals and band gap of different donor systems to be extracted.

Carbon Nanohorns Modified with Conjugated Terthienyl/Terthiophene Structures: Additives to Enhance the Performance of Dye-Sensitized Solar Cells

“…Figure 3 illustrates the synthetic route followed to obtain the corresponding dyes. A full description and characterization of the dyes was reported separately [ 19 ]. The low solubility of these kind of dyes is a drawback that makes difficult their proper characterization by 1 H-NMR or 13 C-NMR spectroscopy, but in owner case a complete NMR study was published.…”

“…As expected, the molar absorptivity and the position of the λ max wavelength not only depends on the numbers of thiophene units, but also on the substitution pattern. In a previously mentioned report, the correspondence between these two parameters have been studied by UV-Vis spectroscopy and computational modelling [ 19 ].…”

“…This assumption would require, however, characterization of electron mobility and lifetime of charge separated states for a more detailed insight into the reasons of the different performance of the terthienyl dyes. Also, no correlation was observed between the IPCE and the degree of dye functionalization determined by TGA measurements that was 732, 335, and 480 μmol dye/g CNHs for samples 1 ‒ 3 , respectively [ 19 ].…”

“…Then, the reaction mixture was filtered and washed with different solvents. The obtained compounds were fully characterized by using a range of techniques including thermogravimetric analysis (TGA), UV-Vis spectroscopy, Raman spectroscopy, fluorescence spectroscopy, and transmission electron microscopy (TEM) [ 19 ].…”

Understanding the Raman enhancement of carbon nanohorns labelled with organic dyes

“…Our group has dedicated intensive research to understanding the Raman enhancement of several oligothiophenes when either adsorbed or covalently grafted to single-walled carbon nanohorns (CNHs). 8,9 CNHs are short single-walled carbon nanotubes that aggregate into spherical particles with a diameter of approximately 100 nm. The properties of CNHs make them very interesting for numerous applications.…”