Graphene-based materials are gaining heightened attention as novel materials for environmental applications The unique physicochemical properties of graphene, notably its exceptionally high surface area, electron mobility, thermal conductivity, and mechanical strength, can lead to novel or improved technologies to address the pressing global environmental challenges This critical review assesses the recent developments in the use of graphene-based materials as sorbent or photocatalytic materials for environmental decontamination, as building blocks for next generation water treatment and desalination membranes, and as electrode materials for contaminant monitoring or removal The most promising areas of research are highlighted, with a discussion of the main challenges that we need to overcome in order to fully realize the exceptional properties of graphene in environmental applications

Environmental applications of graphene-based nanomaterials.

Role of nanomaterials in water treatment applications: a review.

Surface functional groups of carbon-based adsorbents and their roles in the removal of heavy metals from aqueous solutions: A critical review.

A review on heavy metal ions adsorption from water by graphene oxide and its composites

Graphene oxide-supported polyaniline (PANI@GO) composites were synthesized by chemical oxidation and were characterized by SEM, Raman and FT-IR spectroscopy, TGA, potentiometric titrations, and XPS. The characterization indicated that PANI can be grafted onto the surface of GO nanosheets successfully. The sorption of U(VI), Eu(III), Sr(II), and Cs(I) from aqueous solutions as a function of pH and initial concentration on the PANI@GO composites was investigated. The maximum sorption capacities of U(VI), Eu(III), Sr(II), and Cs(I) on the PANI@GO composites at pH 3.0 and T = 298 K calculated from the Langmuir model were 1.03, 1.65, 1.68, and 1.39 mmol·g–1, respectively. According to the XPS analysis of the PANI@GO composites before and after Eu(III) desorption, nitrogen- and oxygen-containing functional groups on the surface of PANI@GO composites were responsible for radionuclide sorption, and that radionuclides can hardly be extracted from the nitrogen-containing functional groups. Therefore, the chemical a...

Highly efficient enrichment of radionuclides on graphene oxide-supported polyaniline

The adsorptive properties of graphene oxide (GO) towards divalent metal ions (copper, zinc, cadmium and lead) were investigated GO prepared through the oxidation of graphite using potassium dichromate was characterized by scanning electron microscopy (SEM), powder X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and infrared spectroscopy (FT-IR) The results of batch experiments and measurements by flame atomic absorption spectrometry (F-AAS) indicate that maximum adsorption can be achieved in broad pH ranges: 3–7 for Cu(II), 5–8 for Zn(II), 4–8 for Cd(II), 3–7 for Pb(II) The maximum adsorption capacities of Cu(II), Zn(II), Cd(II) and Pb(II) on GO at pH = 5 are 294, 345, 530, 1119 mg g−1, respectively The competitive adsorption experiments showed the affinity in the order of Pb(II) > Cu(II) ≫ Cd(II) > Zn(II) Adsorption isotherms and kinetic studies suggest that sorption of metal ions on GO nanosheets is monolayer coverage and adsorption is controlled by chemical adsorption involving the strong surface complexation of metal ions with the oxygen-containing groups on the surface of GO Chemisorption was confirmed by XPS (binding energy and shape of O1s and C1s peaks) of GO with adsorbed metal ions The adsorption experiments show that the dispersibility of GO in water changes remarkably after complexation of metal ions After adsorption, the tendency to agglomerate and precipitate is observed Excellent dispersibility of GO and strong tendency of GO–Me(II) to precipitate open the path to removal of heavy metals from water solution Potential application of GO in analytical chemistry as a solid sorbent for preconcentration of trace elements and in heavy metal ion pollution cleanup results from its maximum adsorption capacities that are much higher than those of any of the currently reported sorbents

Adsorption of divalent metal ions from aqueous solutions using graphene oxide

A dispersive solid-phase microextraction (DSPME) with multiwalled carbon nanotubes (MWCNTs) as solid sorbent and ammonium pyrrolidinedithiocarbamate (APDC) as chelating agent was developed for determination of selenium. In the proposed procedure, the Se(IV)–APDC complex is adsorbed on MWCNTs dispersed in aqueous samples. After the adsorption process, the aqueous samples are filtered and MWCNTs with selenium chelate are collected onto a filter. The loaded filters are directly measured using X-ray fluorescence (XRF) spectrometry. In order to obtain high recovery of the Se ions on MWCNTs, the proposed procedure was optimized for various analytical parameters such as pH, amounts of MWCNTs and APDC, sample volume and time of the sorption process. Under optimized conditions Se ions can be determined with very good recovery (97 ± 3%), precision (RSD = 3.2%) and detection limits (from 0.06 to 0.2 ng mL−1, depending on counting time and XRF equipment). The effect of common coexisting ions was also investigated. Se(IV) can be determined in the presence of heavy metal ions and alkali metals. The chemical interferences observed for high concentrations of Cu(II), Fe(III), and Zn(II) can be completely eliminated using precipitation with NaOH. The proposed method was applied for the determination of Se in mineral water and biological samples (Lobster Hepatopancreas). The proposed method can also be applied for selenium speciation. The concentration of selenate can be obtained as the difference between the concentration of selenite after and before prereduction of selenate to selenite.

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Determination of selenium by X-ray fluorescence spectrometry using dispersive solid-phase microextraction with multiwalled carbon nanotubes as solid sorbent

The source of the differences in the IR spectral properties of the hydrogen bond in two isomeric thioamide crystals: Thioacetanilide and N-methylthiobenzamide

Edyta Turek

Papers

Adsorption of divalent metal ions from aqueous solutions using graphene oxide

Determination of selenium by X-ray fluorescence spectrometry using dispersive solid-phase microextraction with multiwalled carbon nanotubes as solid sorbent

The source of the differences in the IR spectral properties of the hydrogen bond in two isomeric thioamide crystals: Thioacetanilide and N-methylthiobenzamide