Polydopamine Functionalized Graphene Oxide as Membrane Nanofiller: Spectral and Structural Studies

Abstract

High-degree functionalization of graphene oxide (GO) nanoparticles (NPs) using polydopamine (PDA) was conducted to produce polydopamine functionalized graphene oxide nanoparticles (GO-PDA NPs). Aiming to explore their potential use as nanofiller in membrane separation processes, the spectral and structural properties of GO-PDA NPs were comprehensively analyzed. GO NPs were first prepared by the oxidation of graphite via a modified Hummers method. The obtained GO NPs were then functionalized with PDA using a GO:PDA ratio of 1:2 to obtain highly aminated GO NPs. The structural change was evaluated using XRD, FTIR-UATR, Raman spectroscopy, SEM and TEM. Several bands have emerged in the FTIR spectra of GO-PDA attributed to the amine groups of PDA confirming the high functionalization degree of GO NPs. Raman spectra and XRD patterns showed different crystalline structures and defects and higher interlayer spacing of GO-PDA. The change in elemental compositions was confirmed by XPS and CHNSO elemental analysis and showed an emerging N 1s core-level in the GO-PDA survey spectra corresponding to the amine groups of PDA. GO-PDA NPs showed better dispersibility in polar and nonpolar solvents expanding their potential utilization for different purposes. Furthermore, GO and GO-PDA-coated membranes were prepared via pressure-assisted self-assembly technique (PAS) using low concentrations of NPs (1 wt. %). Contact angle measurements showed excellent hydrophilic properties of GO-PDA with an average contact angle of (27.8°).

Study on the Adsorption Properties of Iron Tailings for GO

“…This study mainly studied the adsorption of GO by iron tailings in different solution pH (5,6,7,8,9,10), the mass of iron tailings (30 mg, 40 mg, 50 mg, 60 mg, 70 mg) and the adsorption effect of GO at initial concentrations (40 mg/L, 60 mg/L, 80 mg/L, 100 mg/L) and temperatures (298.15 K, 303.15 K, 313.15 K) and the corresponding adsorption isotherm model, adsorption thermodynamic model and adsorption kinetic model were obtained by fitting the test data.…”

“…In recent years, graphene has strong application prospects in many scientific fields due to its unique electrical, optical, mechanical and other properties and has received extensive attention from many scholars [1][2][3][4]. Graphene oxide (GO) is a derivative of graphene, it is usually synthesized from pure graphite powder by modified Hummers method [5]. It is easy to manufacture, low in cost, rich in oxygen-containing functional groups, has a high specific surface area [6], and is easily dispersed stably in solvents [7].…”

Development of Novel Composite Membranes in Water/Wastewater Treatment

“…Two studies were considered in this Special Issue. The first one is by Alkhouzaam et al [ 5 ] who produced Graphene oxide nanoparticles using the modified Hummer’s method. The obtained GO NP were amine functionalized using the bio-inspired polydopamine (PDA) to increase their hydrophilicity, dispersibility in aqueous and organic solvents, antibacterial properties, surface area, adsorption capacity, mechanical and thermal stability [ 6 , 7 ].…”

Sustainable Innovation in Membrane Technologies for Produced Water Treatment: Challenges and Limitations

“…However, all membranes retained their desalination capabilities despite the addition of the activated carbon. Alkhouzaam et al [39] presented Recent work using fabricated polystyrene membranes along with a novel, activated carbon-doped, electrospun, polystyrene membrane was done by Abdelrazeq et al [37] and Esteves et al [38] to tackle produced water treatment using a bench-scale direct-contact membrane distillation (DCMD) bench-scale unit. Results have shown that membranes including activated carbon-doped layers showed a 20× greater specific surface area as compared to undoped membranes.…”

“…However, all membranes retained their desalination capabilities despite the addition of the activated carbon. Alkhouzaam et al [39] presented another interesting study where polydopamine functionalized graphene oxide nanoparticles (GO-PDA NPs) were prepared to investigate their structural properties in membrane separation processes. The hydrophilicity was significantly improved despite the low concentrations of GO-PDA layer (1 wt.%) on the PS substrate.…”