Efficient surface modification of carbon nanotubes for fabricating high performance CNT based hybrid nanostructures

Abstract

Carbon nanotubes (CNTs) were chemically modified to achieve strong binding strength with the attached functional components as well as good dispersability and nanoparticle sizeuniformity. An efficient multi-oxidation process was developed to create porous out layer with many nanoscale defects on the surface of CNTs for metallic nanoparticle close attachment and bond sufficient oxygen-containing groups, which assisted the dispersion of CNTs in the aqueous solution. The surface modified CNTs have advantages of strong binding capability, large surface area, high mechanical strength and good dispersability, which show great potential as building blocks for hybrid nanomaterials. Monodispersed silver nanoparticles with an average size of 3 nm were formed from inside the created nanoscale defects on the surface of CNTs without any obvious agglomerations. The fabricated hybrid exhibited much enhanced anti-bacterial performance compared to commercial silver nanoparticles due to the combined anti-bacterial effects of CNTs and silver nanoparticles. With these superior properties, the developed surface modification process could be widely

Characterization of Amide and Ester Functionalized Multiwalled Carbon Nanotubes

“…Comparing the ratio ID/IG values of as received MWCNT and MWCNT-carboxylic, it is observed that after functionalization, the ratio values increase as expected (Table-2). The oxidation of MWCNT breaks some of its bonds and inserts chemical groups that can be interpreted as defects on the structure [13]. But, after ester and amide functionalization, the values decreasing.…”

Effect of MWCNT-modified graphite felts on hexavalent chromium removal in biocathode microbial fuel cells

“…This difference might be attributed to the oxidative acid pretreatment, which could be able to form large amount of oxygen-containing groups on the surface of MWCNTs 29 and also create porous out layer with much abundant nanoscale defects. 30 The MWCNTs with oxygencontaining groups and nanoscale defects achieved better dispersibility and stability 29,30 in aqueous solution, which might FT-IR was further employed to investigate the functional groups induced by the oxidative acid pretreatment of MWCNTs. Fig.…”

“…Besides, the broad peak at 1220-1080 cm À1 representing the stretching vibration of C-O from carboxyl groups increased as well. 29,30 These intensied peaks and newly generated peaks indicated that the acid pretreatment offered more carboxyl containing functional groups on the O-MWCNTs surface, which could effectively improve the dispersibility of O-MWCNTs in aqueous systems. This was also veried in other studies.…”

“…This was also veried in other studies. [28][29][30]36 The surface characteristic analyses of the three electrodes were conducted in terms of SSA, contact angle, and surface resistance ( Table 1). The MWCNTs modications improved the SSA of the graphite felt dramatically, as the SSA values of the MWCNTs (29.84 AE 0.56 m 2 g À1 ) and O-MWCNTs (66.98 AE 0.43 m 2 g À1 ) electrode were almost 4 and 9 times higher than that of the control electrode, respectively.…”

“…27 As a result of oxidizing acid attack, oxygen-containing groups can be attached to the ends and surfaces of MWCNTs to improve the dispersion of MWCNTs in the aqueous solution. [28][29][30] Furthermore, the oxidized MWCNTs-modied electrode, compared to the original MWCNTs-modied one, caused a higher efficiency of power generation and wastewater treatment in MFCs. 31 The aim of this study was to investigate the effect of two kinds of MWCNTs (original and oxidized MWCNTs)-modied graphite felts as biocathode electrodes in Cr(VI)-reducing MFCs.…”