Microscopic and Spectroscopic Investigation of Poly(3-hexylthiophene) Interaction with Carbon Nanotubes

Abstract

Abstract:The inclusion of carbon nanotubes in polymer matrix has been proposed to enhance the polymer's physical and electrical properties. In this study, microscopic and spectroscopic techniques are used to investigate the interaction between poly(3-hexylthiophene) (P3HT) and nanotubes and the reciprocal modification of physical properties. The presence of P3HT-covered nanotubes dispersed in the polymer matrix has been observed by atomic force microscopy and transmission electron microscopy. Then, the modification of P3HT optical properties due to nanotube inclusion has been evidenced with spectroscopic techniques like absorption and Raman spectroscopy. The study is completed with detailed nanoscale analysis by scanning probe techniques. The ordered self assembly of polymer adhering on the nanotube is unveiled by showing an example of helical wrapping of P3HT. Scanning tunneling spectroscopy study provides information on the electronic structure of nanotube-polymer assembly, revealing the charge transfer from P3HT to the nanotube.

Hybrid Carbon Nanotube Networks as Efficient Hole Extraction Layers for Organic Photovoltaics

“…In terms of the geometry of rr-P3HT in the presence of SWNTs, previous reports on nanohybrids prepared using techniques similar to that described in this work have indicated experimentally (through scanning probe microscopic techniques) as well as computationally, a natural tendency for the rr-P3HT to wrap around SWNTs due to π-π type super-molecular interactions. 10,[21][22][23][24] To ascertain this fact further and to obtain a better understanding of the non-covalent functionalization process, optical absorption, valence and core level X-ray spectroscopy (XPS) measurements were carried out on the rr-P3HT/s-SWNT nanohybrid system. A representative UV-Vis absorbance spectrum for rr-P3HT/s-SWNT nanohybrids in 1,2-dichlorobenzene is shown in Fig.…”

Ultrafast interface charge transfer dynamics on P3HT/MWCNT nanocomposites probed by resonant Auger spectroscopy

“…Moreover, according to several morphological studies on P3HT/Fe-MWCNT nanocomposites the polymer wraps around the nanotube. [24][25][26]41,56 Thus, this conguration between P3HT and Fe-MWCNT may reduce the p-p interchain stacking of P3HT polymer and consequently affect the intensity of peak 1 as observed by the S 1s NEXAFS spectrum.…”

“…22,23 Many reports about the morphological, optical and electronic properties of P3HT-CNT nanocomposites and their relationship with preparation routes can be found in the literature. 19,20,[24][25][26][27][28] In this sense, it is known that the interfacial charge transfer process between P3HT and CNTs species has an important role in the device performance, considering photodiodes, sensors or OFETs. On the other hand, this process can be notably affected by many factors such as interface hybridization and lm ordering and morphology.…”

Evidence of Conjugation Enhancement in P3HT/SWNT Mixtures for Organic Photovoltaics

“…According to Heller et al [13], a down-shift of the P3HT peak centered at 1454 cm -1 can be associated with an extended conjugation length which can be therefore attributed to the MWNTs templating effect. On the other hand, the up-shift of the remaining peaks attributed to MWNTs is likely related to nanotube compression from the P3HT adsorbed at their surface [14].…”