Non-covalent ruthenium polypyridyl complexes–carbon nanotubes composites: an alternative for functional dissolution of carbon nanotubes in solution

Abstract

The dispersion of single-walled carbon nanotubes (SWCNTs) in the presence of water soluble polypyridyl complexes of the general formula [Ru(x)(bpy)(y)L](2+) (L = dppz, dppn, tpphz) is reported. These ligands have extended planar π systems, which aid in the solubilization of SWCNTs via π-π interactions.

Non-covalent functionalization of carbon nano-onions with pyrene–BODIPY dyads for biological imaging

“…The use of π-πinteractions for the non-covalent functionalization of carbon nanotubes (CNTs) with molecules bearing extended π-systems is a well-established protocol. 13 Prominent examples include the immobilization of metal complexes, 14,15 crown ethers, 16,17 tetrapyrrole macrocycles, 18,19,20,21,22 and guanosine derivatives, 23 next to many others. Also the immobilization of pyrene derivatives on the sidewalls of CNTs promoted by π-πstacking has been extensively studied.…”

Carbon nanotubes dispersed in aqueous solution by ruthenium(ii) polypyridyl complexes

“…This can be attributed to π-π stacking of the pyrene anchors of RuPy1 onto the sidewalls of SWCNTs. 16 Experiments using RuPy1, with initial concentration of 0 mg mL −1 (black line), 1 mg mL…”

“…16 Although high concentration of SWCNTs are dispersible in aqueous solutions using [Ru(bpy) 2 (dppz)] 2+ , its short-lived and non-emissive excited state in aqueous solution limits the excited state interactions between the metal complex and CNTs. 21,22 In this study, we synthesized two ruthenium complexes containing pyrene-anchoring groups -Scheme 1.…”

“…To date, many approaches have been developed to individualize carbon nanotubes and most of them are simply divided into two categories, that is, covalent functionalization, 17,18 versus non-covalent functionalization. 16,19,20 On the one hand, covalent functionalization is an effective approach for attaching functional groups to the sidewalls of carbon nanotubes. Although covalent functionalization enables CNT's dispersion in different solvents, the process involves the chemical modification of SWCNTs.…”

“…Bulk bundled SWCNTs require individualization in order to fully exploit their mechanical, electronic, and optical properties. [13][14][15][16] A general approach to debundle SWCNTs is to introduce repulsive interactions between them to counterbalance short-range attractions. To date, many approaches have been developed to individualize carbon nanotubes and most of them are simply divided into two categories, that is, covalent functionalization, 17,18 versus non-covalent functionalization.…”