Noncovalently modified carbon nanotubes with carboxymethylated chitosan: a controllable donor-acceptor nanohybrid

Dewu Long; Guozhong Wu; Guanglai Zhu

doi:10.3390/ijms9020120

Noncovalently modified carbon nanotubes with carboxymethylated chitosan: a controllable donor-acceptor nanohybrid

Int J Mol Sci. 2008 Feb;9(2):120-130. doi: 10.3390/ijms9020120. Epub 2008 Feb 5.

Authors

Dewu Long¹, Guozhong Wu¹, Guanglai Zhu¹

Affiliation

¹ Department of Nuclear Analysis, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai, 201800 China.

Abstract

We report here the modification of multiwalled carbon nanotubes (MWNTs) with a kind of polysaccharide, carboxymethylated chitosan (cmCs), and their potential usage as donor-acceptor nanohybrids. The modified composites (cmCs/MWNTs) were characterized by high-resolution TEM, FT-IR, TGA and time-resolved spectroscopy. The time-resolved spectroscopic experiments revealed that interfacial electron transfer readily takes place between MWNTs and surface immobilized cmCs chains. The forward electron transfer is fast (< 20 ns) while the backward recombination is slow. The recombination process strongly depends on the chain length of carboxylmethylated chitosan, i.e. a shorter recombination lifetime (~1.1 micros) for the shorter-chain cmCs coated MWNTs against that of the longer-chain cmCs coated MWNTs (~3.5 micros). The results demonstrated that the cmCs/MWNTs composite may be applied as a controllable donor-acceptor nanohybrid.

Keywords: carboxymethylated chitosan; charge separation; donor-accepter nanohybrid; multiwalled carbon nanotubes.