Noncovalent Modification of Single-Walled Carbon Nanotubes Using Thermally Cleavable Polythiophenes for Solution-Processed Thermoelectric Films

Abstract

Four thermally cleavable polythiophene derivatives containing carbonate and solubilizing groups were synthesized for noncovalent modification of single-walled carbon nanotubes (SWCNTs). A well-dispersed polythiophene/SWCNTs composite was obtained by adsorption of the polymer at the SWCNT surface. The solution-processed composite film exhibited solid-state thermal cleavage of the insulating solubilizing group through decarboxylation, producing an insoluble composite film. The thermally cleavable composite film was evaluated for potential application as a thermoelectric (TE) material. The electrical conductivity (σ) of the thermally treated composite film was up to 250 times higher than that of the as-prepared composite film. The increased σ contributed to an increase in the power factor (PF). The ethanol-processed composite film could be applicable for green processing of a TE material using the less-toxic solvent. The substrate-free polythiophene/SWCNTs composite film prepared by simple solvent evaporation yielded a figure-ofmerit of 3.1 × 10 −2 with a PF of 28.8 μW m −1 K −2 at 25 °C. This solution-processed methodology is beneficial for the development of a flexible TE material.

Photoinduced electron transfer processes of single-wall carbon nanotube (SWCNT)–based hybrids

“…Polymers like regioregular poly(3alkylthiophene)s (P3AT) [33], poly(9,9-dialkylfluorene)s [34][35][36], poly(phenylene vinylene) (PPV) [37] and poly(phenylene ethynylenes) [38] were demonstrated to be efficient SWCNT dispersants, some of which presented excellent SWCNT diameter and chirality selectivity [32]. Functional molecules/groups covalently linked to the polymer side chain which act as the pending arms along the polymer main chain have been reported [39][40][41]. Meanwhile, strong electron acceptros or metal complexes immobilized into the polymer main chain and directly placed on the surface of SWCNT is another method to endow the polymer/SWCNT hybrids unique properties [42][43][44].…”

Noncovalent Functionalization of Single-Walled Carbon Nanotubes with a Photocleavable Polythiophene Derivative

“…However, the solubilizing conjugated polymer remains attached to the surface of the SWCNTs, meaning that the resulting film can be damaged upon exposure to the solvent in which it was made. Therefore, the fabrication of insoluble SWCNT films using functional dispersants would benefit their practical application [ 15 ].…”

Syntheses and Structures of Keggin-Type Polyoxometalate Crystals Hybridized with a Polymerizable Ionic-Liquid

“…Ionic-liquids are an attractive class of organic molten electrolytes having characteristic properties such as conductivity, catalysis, and separation abilities [1][2][3][4][5][6][7][8]. The combination of ionic-liquids with other inorganics bringing additional properties can lead to the construction of functional inorganic-organic hybrid materials [9][10][11][12]. Polyoxometalate (POM) clusters having several physicochemical properties are promising counter parts [13][14][15][16][17][18][19][20][21][22][23][24].…”