A strong adsorbent for Cu2+: graphene oxide modified with triethanolamine

Abstract

A strong adsorbent TEA-GO for Cu(2+) is prepared using TEA modified GO nanosheets. FT-IR and XPS results show that epoxy groups on GO are eliminated, and simultaneously hydroxyl groups and C-N dominate the surface groups of TEA-GO. The increased equilibrium capacity of TEA-GO for a high initial concentration of Cu(2+) makes it a promising adsorbent for heavy metal ions.

Fabrication of Stacked Graphene Oxide Nanosheet Membranes Using Triethanolamine as a Crosslinker and Mild Reducing Agent for Water Treatment

“…The whole spectra can be divided into 5 peaks: C-OH, C-O-C, C=O, C=O-O and C-C. On the other hand, the huge peaks of C-C and C-O-C were observed at 285.0–287.5 eV for GO-TEOA membranes. The entire spectra consists of 6 peaks of C-N for GO modified with TEOA and C-OH, C-O-C, C=O, C=O-O and C-C for GO [33]. For all GO-TEOA membranes, it was found that the ratio of C-C, C-OH and C-N increased but that of C-O-C, C=O and C=O-O decreased compared with the unmodified GO membrane.…”

“…These Raman and XPS spectra indicate that the oxygen-containing functional groups in GO-TEOA membranes were slightly reduced. Liu G. et al, reported that TEOA has a mild reducing ability as a chemical modifier [33]. The N + groups formed by hydrolysis of TEOA are used for ring-opening reactions of epoxides, which leads to the formation of C=C bonds.…”

“…In contrast, for the GO-TEOA membrane fabricated with TEOA/GO = 0.5, the ζ-potential was weakened by the introduction of TEOA and found to be dependent on pH, with an iso-electric point of approximately 3.7. It has been reported that N + groups in TEOA form quaternary nitrogen species with carboxyl groups on GO surfaces via electrostatic interaction [33]. Thus, for GO-TEOA membranes, it is assumed that TEOA molecules were intercalated into the interlayers via electrostatic interaction, resulting in the attenuation of the negative charge of GO nanosheets.…”

“…The XPS analysis indicates that TEOA molecules exist in the fabricated GO nanosheet membranes. During the formation of quaternary nitrogen species, hydroxyl groups in TEOA can be introduced onto the GO [33]. Thus, TEOA can crosslink the GO nanosheet layers effectively via electrostatic interactions between N + groups in TEOA and carboxyl groups on GO and via hydrogen bonding between hydroxyl groups of TEOA, that strengthen the final membrane.…”

Graphene oxide/polydimethylsiloxane composite sponge for removing Pb(ii) from water

“…37 Introducing GO resulted in the appearance of stretching vibration bands at 1732, 1623, and 1040 cm À1 , corresponding to C]O, C]C, and C-O-C groups. 18,[38][39][40] These functional groups are present in GO. 36 The adsorption of adsorbates onto GO-PDMS is expected to proceed via chelation The contact time is a key parameter affecting whether heavy metal sorption reaches equilibrium.…”