Amphiphilic carbonaceous materials: preparation methods and applications

Abstract

Although most carbon materials are hydrophobic, their oxidation would add hydrophilic functional groups onto their surfaces, making them amphiphiles. In this review, amphiphilic carbonaceous materials are reviewed, focusing on their preparation methods, compositions, and properties associated with their structural models. In addition, a variety of applications arising from their amphiphilicity are mentioned, including organic-free carbon coatings, fabrication of nanoporous structures in carbons, carbon supports for metal nanoparticles, environmental remediation, monitoring of toxic gases, dispersing agents, and biomedical applications.

Fig. 1. (a) AFM image in tapping mode of ACM-CP on a mica flake and (b) height distribution of the particle in (a). Reproduced from ref. with permission from the Royal Society of Chemistry, copyright 2013.

Fig. 2. Flow diagram for the preparation of ACMs.

Fig. 3. ACMs derived from coal tar pitch (CP) and green coke (GC): (a) FTIR and (b) N 1s XPS spectra. Reproduced from ref. with permission from the Royal Society of Chemistry, copyright 2013. Reproduced from ref. with permission from Science Press, copyright 2015.

Fig. 4. TPD profiles of (a and b) ACM-CP and (c and d) ACM-GC. Reproduced from ref. with permission from Elsevier Ltd, copyright 2016.

Fig. 5. Structural model for ACM-CP. Reproduced from ref. with permission from the American Chemical Society, copyright 2014.

Fig. 6. Effects of concentration of ACM and pH on the gelation time of a mesophase-pitch-derived ACM in an NH₃·H₂O aqueous solution at 25 °C. Reproduced from ref. with permission from Elsevier Ltd, copyright 1991.

Fig. 7. ACMs prepared from raw coke: TG and DTA curves (10 °C min⁻¹) for (a) ACM and (b) its dry gel prepared in NH₃·H₂O, and (c) changes in d₀₀₂ interlayer spacing and L_c(002) crystallite size with heat treatment temperature for the pristine raw coke, ACM and its dry gel. Reproduced from ref. with permission from the Carbon Society of Japan, copyright 1993.

Fig. 8. Chemical structure models of (a) graphene oxide (GnO) and (b) reduced GnO (rGnO). Reproduced from ref. with permission from De Gruyter as part of a partnership with IUPAC, copyright 2011.

Fig. 9. Changes in the zeta potential with pH for GnOs. Reproduced from ref. with permission from De Gruyter, as part of a partnership with IUPAC, copyright 2011.

Fig. 10. AC conductivity (σ_AC) of a GnO film: (a) temperature dependence at 100 Hz and (b) frequency, ω, dependence at different temperatures. Reproduced from ref. with permission from Elsevier Ltd, copyright 2015.

Fig. 11. Stress–strain behavior of GnO films under tension: (a) stress–strain curve and (b) loading-unloading in region I in (a). Reproduced from ref. with permission from Springer Nature Publishing Group, copyright 2007.

Fig. 12. XPS spectra for GnO films prepared using Hummers' method after deposition on Si₃N₄/SiO₂ substrate and after heat-treatment at 500 °C: (a) C 1s and (b) O 1s spectra. Reproduced from ref. with permission from Elsevier Ltd, copyright 2010.

Fig. 13. XPS C 1s spectra of (a) as-prepared GnO film and (b) after 450 W microwave irradiation for 20 min . Reproduced from ref. with permission from Elsevier Ltd, copyright 2015.

Fig. 14. Illustration of the synthesis of graphene-based AJNs using temporary substrates of starch microspheres. Reproduced from ref. with permission from Elsevier Ltd, copyright 2018.

Fig. 15. Contact angles of water droplets on surfaces of AJN (a and b) and JSGO (c and d). (a and c) are on hydrophilic surfaces while (b and d) are on hydrophobic surfaces. Reproduced from ref. with permission from Elsevier Ltd, copyright 2018; reproduced from ref. with permission from Elsevier Ltd, copyright 2022.

Fig. 16. Structural model for humic acid with the chemical composition of C₃₀₈H₃₂₈O₉₀N₅. Reproduced from ref. with permission from Springer Berlin Heidelberg, copyright 1993.

Fig. 17. FTIR spectra of biotechnology humic acid (BHA) and leonardite humic acid (LHA). Reproduced from ref. with permission from Elsevier Ltd, copyright 2014.

Fig. 18. Changes in zeta potentials with the concentration of aqueous solutions of leonardite humic acid (LHA), biotechnology humic acid (BHA), and leonardite fulvic acid (LFA) in comparison to that of a coke-derived ACM. Reproduced from ref. with permission from Elsevier Ltd, copyright 2014.

Fig. 19. Possible structural models for (a) F–S and (b) F–T. Reproduced from ref. with permission from the Royal Society of Chemistry, copyright 2014.

Fig. 20. Amphiphilic carbon dots (ACDs) synthesized from nonionic surfactants, alkyl glycosides with different alkyl chains including APG06, APG10, and APG1214 (coded as C₆-ACD, C₁₀-ACD and C₁₂₁₄-ACD, respectively): (a) TEM image with a crystalline lattice image (inset) and (b) particle size distribution of C₁₂₁₄-ACD; (c) surface tension curves (25 °C) of C₆-ACD, C₁₀-ACD and C₁₂₁₄-ACD comparing with nonionic APG1214; (d) surface tension curves of C₁₂₁₄-ACD in comparison with the pristine surfactants including H-ACD, nonionic APG1214  and anionic SDBD. Reproduced from ref. with permission from Elsevier Ltd, copyright 2024; reproduced from ref. with permission from the Royal Society of Chemistry, copyright 2019.

Fig. 21. N₂ adsorption/desorption isotherms at 77 K for mesoporous carbons prepared from ACM-GC: effects of (a) KOH/ACM ratio, (b) heat treatment temperature and (c) heating time. Reproduced from ref. with permission from Elsevier Ltd, copyright 2011.

Fig. 22. Symmetric EDLC of nanoporous carbons derived from ACM-CP with KOH/ACM ratio of 1.5/1 with 6 M KOH aqueous electrolyte: (a) charge/discharge curves at different current densities and (b) rate performance up to 100 A g⁻¹. Reproduced from ref. with permission from the Royal Society of Chemistry, copyright 2013.

Fig. 23. Asymmetric capacitor of MnO₂|1 M Na₂SO₄ aqueous electrolyte|ACM-CP-derived carbon: (a) charge/discharge curves at different current densities and (b) rate performance. Reproduced from ref. with permission from the Royal Society of Chemistry, copyright 2013.

Fig. 24. Rate and cycle performances (inset) of LHA- and BHA-derived nanoporous carbons. Reproduced from ref. with permission from Elsevier Ltd, copyright 2014.

Fig. 25. Histogram of the different types of pores in carbons prepared from anthracite under various pre-oxidation conditions. The number shown for each column is total oxygen content (μmol g⁻¹) after pre-oxidation. Reproduced from ref. with permission from Elsevier Ltd, copyright 1997.

Fig. 26. Oxidation and activation of a bituminous coal: (a) yield of humin and humic acid as a function of HNO₃ normality and (b) S_BET of the resultant activated carbons as a function of KOH/coal ratio and HNO₃ normality used for oxidation. Reproduced from ref. with permission from Elsevier Ltd, copyright 1995.

Fig. 27. N₂ adsorption isotherms of the activated carbons derived from petroleum coke with or without pre-oxidation. Reproduced from ref. with permission from Elsevier Ltd, copyright 2008.

Fig. 28. LIBs using graphite anode with or without carbon-coating by ACM-GC: (a) charge/discharge curves and (b) cyclic performances at 50 mA g⁻¹. Reproduced from ref. with permission from Elsevier Ltd, copyright 2010.

Fig. 29. (a) SEM image and (b)TEM image of carbon-coated Li₄Ti₅O₁₂ using ACM-GC. Reproduced from ref. with permission from Elsevier Ltd, copyright 2012.

Fig. 30. LIB performances of Li₄Ti₅O₁₂ (LTO) anode coated with ACM-GC: (a) rate performances as a function of ACM-GC dosage and (b) cycle performances of LTO coated with ACM-GC at 10 mg_ACM/g_LTO dosage at different rates. Reproduced from ref. with permission from Elsevier Ltd, copyright 2012.

Fig. 31. Cyclic performances of LIBs with carbon-coated LiFePO₄ cathode by ACM-CP: (a) discharge capacities at different current densities from 0.1C to 60C and (b) discharge capacity and coulombic efficiency vs. cycle numbers up to 1000 cycles at 10C rate. Reproduced from ref. with permission from Elsevier Ltd, copyright 2014.

Fig. 32. Diameter distribution of Pt particles loaded on ACMs after heat treatment at different temperatures of (a) 500 °C, (b) 700 °C and (c) 1000 °C. Reproduced from ref. with permission from Elsevier Ltd, copyright 1996.

Fig. 33. Conversion of pivalic acid over sulfonated carbon catalysts (F–S and F–T) in comparison with two commercially available catalysts (Amberlyst-15 and Nafion-15) at 70 °C: (a) conversion kinetics using various catalysts (catalyst: 0.5 g, pivalic acid: 1.02 g and methanol: 1.60 g) and (b) effect of catalyst amount (pivalic acid: 1.02 g and methanol:1.60 g). Reproduced from ref. with permission from the Royal Society of Chemistry, copyright 2014.

Fig. 34. SEM and TEM images of MnO₂ particles prepared from MnCO₃/ACM mixture: (a–c) hollow cubes and (d–f) hollow spheres. (a and d) SEM images, and (b, c, e and f) TEM images. Reproduced from ref. with permission from the American Chemical Society, copyright 2014.

Fig. 35. SEM and TEM images of carbon vesicles: (a and b) before carbonization and (c and d) after carbonization. Reproduced from ref. with permission from Elsevier Ltd, copyright 2004.

Fig. 36. Few-layered graphene oxide (GnO) helps dispersion of multi-walled carbon nanotubes in deionized water: (a) immediately after sonication and (b) absorbance of the two suspensions in (a) vs. standing still time. Reproduced from ref. with permission from the American Chemical Society, copyright 2010.

Fig. 37. Schematic of the mechanism for separating H₂O from isopropanol using a pressure-assisted self-assembled few-layered GnO film. Reproduced from ref. with permission from Elsevier Ltd, copyright 2014.

Fig. 38. Phase boundary photocatalysis of TEMB-CNNS for nitrobenzene reduction: production of aniline (a) in water phase, (b) under various conditions, and (c) for different oil phases. Reproduced from ref. with permission from the Royal Society of Chemistry, copyright 2019.

Fig. 39. Water-permeable GnO films: (a) digital photograph of the film and (b) weight loss of water for a container sealed with a GnO film (film thickness ≈ 1 μm; aperture area ≈ 1 cm²). No loss was detected for ethanol, and hexane, but water was evaporated from the container as freely as through an open aperture. Reproduced from ref. with permission from the American Association for the Advancement of Science, copyright 2012.

Fig. 40. Antibacterial activities of GnO and rGnO nanowalls towards: (a) E. coli and (b) S. aureus. Reproduced from ref. with permission from the American Chemical Society, copyright 2010.

Ming-ming Chen

Cheng-yang Wang

Masahiro Toyoda

Michio Inagaki