Graphene Oxide Obtained by Different Methods: Comparison
Please note this is a comparison between Version 2 by Jessie Wu and Version 1 by Anisoara Oubraham.

Two-dimensional sp2 hybridized graphene has become a material of choice in research due to the excellent properties it displays electrically, thermally, optically and mechanically. Noble nanomaterials also present special physical and chemical properties and, therefore, they provide model building blocks in modifying nanoscale structures for various applications, ranging from nanomedicine to catalysis and optics. The introduction of noble metal nanoparticles (NPs) (Au, Ag and Pd) into chemically derived graphene is important in opening new avenues for both materials in different fields where they can provide hybrid materials with exceptional performance due to the synergistical result of the specific properties of each of the materials. 

  • catalytic
  • metal
  • nanoparticles

2. Methods of Synthesis NPs@GO Nanocomposites

1. Chemical Reduction

Chemical reduction is the most commonly used method to effectively immobilize noble metal nanoparticles (NPs on GO) on graphene oxide (GO) and rGOeduced graphene oxide (rGO). This method involves noble metal ions in solution being reduced to NPs on GO nanowires through additional reductants such as NaBH4, ascorbic acid, sodium citrate or hydrazine (Figure 1). Usually, the GO and rGO dispersion is firstly mixed with noble metal salt solutions, following which the noble metal ions begin adsorbing on the GO and rGO nanosheet surface through electrostatic interaction. Following this, the reducing agents in the mixture reduce the noble metal ions adsorbed in NPs on GO and rGO nanowires [24][1].
Figure 1.
Chemical reduction synthesis of noble metal nanocomposites.
The three fundamental steps constituting the reduction process are as follows: (1) adsorption/reduction, (2) nucleation and (3) growth. The presence of oxygen-containing functional groups on the surface of the GO and rGO favors the adsorption of free metal ions through electrostatic interactions, followed by the reduction in metal ions by a reducing agent and finally the growth of NPs on the GO and rGO sheets. In spite of the formation of MNPs by chemical reduction being a facile process, this technique is limited due to difficulties sterned from size and morphology of the NPs, which can potentially result in polydisperse and large sizes of on GO and rGO surfaces [18][2].

2. Thermally Assisted Method

The thermally assisted method is one of the important methods used to fabricate NPs@GO nanocomposites more simply at high temperature (Figure 2) [13][3]. Thermally assisted synthesis is an easy and efficient method used to immobilize NPs on GO. The speed of the process makes the size and the distribution of the NPs@GO, in this case, difficult to control.
Figure 2.
Thermally assisted synthesis of noble metal nanocomposites.

3. Microwave Irradiation Method

In recent years, microwave irradiation has been used as an eco-friendly method in the synthesizing organic, inorganic and inorganic–organic hybrid materials due to its well-known advantages over conventional synthetic methods. The size as well as distribution of NPs synthesized using the light or microwave irradiation method could be easily controlled compared to reductant-assisted or thermal-assisted reduction method, by changing the intensity, power and irradiation time of the light or microwave (Figure 3). Another important property of microwave irradiation synthesis is that along with the reduction in metals, simultaneous reduction in graphene oxide is possible [13][3].
Figure 3.
Microwave irradiation synthesis of noble metal nanocomposites.

4. Ultrasonication Method

The ultrasonic method (Figure 4) leads to the rapid heating of the liquid to temperatures of 5000 K in a few nanoseconds, resulting in microbubbles with an effective effect. These microbubbles act as chemical reactors. Oxidative and reducing radicals are generated in the cavitation effect during sonolysis. Sonication in the range of 20 to 1000 kHz leads to the formation of MNPs from metal precursor solution. The collapse of these microbubbles leads to the generation of high temperatures inside the bubbles [18][2]. Ultrasonic testing techniques are widely accepted for testing materials in many industries, including power generation, steel, aluminum, titanium production, airframe manufacturing, jet engine manufacturing and shipbuilding [42][4].
Figure 4.
Ultrasonic-assisted synthesis of noble metal nanocomposites.

35. Advantages and Disadvantages of the Synthesis Methods of Noble Metals Functionalized on Graphene Oxide

In recent years, different methods have been proposed for the synthesis of nanoparticles deposited on a graphene support. The choice of the most suitable method has the greatest importance in terms of the structure and catalytic efficiency of the catalysts. Table 1 presents the advantages, disadvantages and applications of the most known methods used in the synthesis of nanoparticles deposited on a graphene support.
In conclusion, the most valuable method among the preparation methods of graphene-deposited nanomaterial catalysts is microwave field irradiation, especially due to the short synthesis time, the fast and uniform heating and the significant challenge in controlling uniformity of the metal nanoparticle’s decoration on the graphene surface. By applying irradiation in the microwave field, under the influence of temperature, homogeneous reaction centers are formed in the reaction medium at the interface between the irradiation-sensitive graphene support and the metal precursor. Additionally, the presence of a reducing agent in the reaction medium means that the precursor can be converted to its metallic form by microwave irradiation.
The qualities of noble metals have demonstrated a special efficiency in the electrocatalytic activity and the electrochemical stability of compounds based on carbon and graphene oxide. In order to improve the oxygen reduction reaction (ORR) and the quality of hydrogen adsorption and desorption, a higher electrochemical active surface area (ECSA) of the catalyst based on noble metals is necessary. The intrinsic increase in the active surface is proportional to the metal content in the chemical compound and to the dispersion of metal nanoparticles on the rGO sheets. The uniform distribution and surface morphology of noble metal nanoparticles on rGO have an effect on the ORR. An excessive reaction energy can cause an agglomeration of the noble metal nanoparticles, leading to particle sizes over 10 nm and the suppression of catalytic activity by reducing the active surface. Figure 5 present the trend of noble metal nanocomposites synthesis methods in different applications. Thus, it can be seen that the most applications of graphene functionalized with noble metals are in applications with fuel cells, renewable energy sources (photovoltaics, production of green hydrogen) and supercapacitors.
Figure 5.
The trend of noble metal nanocomposites synthesis methods in different applications.

References

  1. Guo, J.; Li, X.; Duan, H.; Zhang, H.; Jia, Q.; Zhang, S. Graphene supported Pt–Ni bimetallic nanoparticles for efficient hydrogen generation from KBH4/NH3BH3 hydrolysis. Int. J. Hydrog. Energy 2022, 47, 11601–11610.
  2. Darabdhara, G.; Das, M.R.; Singh, S.P.; Rengan, A.K.; Szunerits, S.; Boukherroub, R. Ag and Au nanoparticles/reduced graphene oxide composite materials: Synthesis and application in diagnostics and therapeutics. Adv. Colloid Interface Sci. 2019, 271, 101991.
  3. Yang, W.; Pan, M.; Huang, C.; Zhao, Z.; Wang, J.; Zeng, H. Graphene oxide-based noble-metal nanoparticles composites for environmental application. Compos. Commun. 2021, 24, 100645.
  4. Available online: https://www.bindt.org/What-is-NDT/Ultrasonic-methods (accessed on 26 August 2022).
  5. Vinodgopal, K.; Neppolian, B.; Salleh, N.; Lightcap, I.V.; Grieser, F.; Ashokkumar, M.; Ding, T.T.; Kamat, P.V. Dual-frequency ultrasound for designing two-dimensional catalyst surface: Reduced graphene oxide–Pt composite. Colloids Surf. A Physicochem. Eng. Asp. 2012, 409, 81–87.
  6. Sontakke, A.D.; Purkait, M.K. A brief review on graphene oxide Nanoscrolls: Structure, Synthesis, characterization and scope of applications. Chem. Eng. J. 2021, 420, 129914.
  7. Tafoya, J.P.V.; Doszczeczko, S.; Titirici, M.M.; Sobrido, A.B.J. Enhancement of the electrocatalytic activity for the oxygen reduction reaction of boron-doped reduced graphene oxide via ultrasonic treatment. Int. J. Hydrog. Energy 2022, 47, 5462–5473.
  8. Ruiz-Camacho, B.; Palafox-Segoviano, J.A.; Pérez-Díaz, P.J.; Medina-Ramírez, A. Synthesis of supported Pt nanoparticles by sonication for ORR: Effect of the graphene oxide-carbon composite. Int. J. Hydrog. Energy 2021, 46, 26027–26039.
  9. Andryushina, N.S.; Stroyuk, A.L.; Ustavytska, O.O.; Kurys, Y.I.; Kuchmy, S.Y.; Koshechko, V.G.; Pokhodenko, V.D.; Stroyuk, O. Graphene Oxide Composites with Silver Nanoparticles: Photochemical Formation and Electrocatalytic Activity in the Oxidation of Methanol and Formaldehyde. Theor. Exp. Chem. 2014, 50, 155–161.
  10. Hu, J.Y.; Li, Z.; Zhai, C.Y.; Wang, J.F.; Zeng, L.X.; Zhu, M.S. Plasmonic photo-assisted electrochemical sensor for detection of trace lead ions based on Au anchored on two-dimensional g-C3N4/graphene nanosheets. Rare Met. 2021, 40, 1727–1737.
  11. Pattananuwat, P.; Khampuanbut, A.; Haromae, H. Novel electrode composites of mixed bismuth-iron oxide/graphene utilizing for photo assisted supercapacitors. Electrochim. Acta 2021, 370, 137741.
  12. Hernández-Majalca, B.C.; Meléndez-Zaragoza, M.J.; Salinas-Gutiérrez, J.M.; López-Ortiz, A.; Collins-Martínez, V. Visible-light photo-assisted synthesis of GO-TiO2 composites for the photocatalytic hydrogen production. Int. J. Hydrog. Energy 2019, 44, 12381–12389.
  13. Menazea, A.; Ahmed, M. Silver and copper oxide nanoparticles-decorated graphene oxide via pulsed laser ablation technique: Preparation, characterization, and photoactivated antibacterial activity. Nano-Struct. Nano-Objects 2020, 22, 100464.
  14. Moqbel, R.A.; Gondal, M.A.; Qahtan, T.F.; Dastageer, M.A. Synthesis of cadmium sulfide-reduced graphene oxide nanocomposites by pulsed laser ablation in liquid for the enhanced photocatalytic reactions in the visible light. Int. J. Energy Res. 2018, 42, 1487–1495.
  15. Yogesh, G.K.; Shukla, S.; Sastikumar, D.; Koinkar, P. Progress in pulsed laser ablation in liquid (PLAL) technique for the synthesis of carbon nanomaterials: A review. Appl. Phys. A 2021, 127, 810.
  16. Ghavidel, E.; Sari, A.H.; Dorranian, D. Experimental investigation of the effects of different liquid environments on the graphene oxide produced by laser ablation method. Opt. Laser Technol. 2018, 103, 155–162.
  17. Guex, L.G.; Sacchi, B.; Peuvot, K.F.; Andersson, R.L.; Pourrahimi, A.M.; Ström, V.; Farris, S.; Olsson, R.T. Experimental review: Chemical reduction of graphene oxide (GO) to reduced graphene oxide (rGO) by aqueous chemistry. Nanoscale 2017, 9, 9562–9571.
  18. Ambrosi, A.; Chua, C.K.; Khezri, B.; Sofer, Z.; Webster, R.D.; Pumera, M. Chemically reduced graphene contains inherent metallic impurities present in parent natural and synthetic graphite. Proc. Natl. Acad. Sci. USA 2012, 109, 12899–12904.
  19. Kurian, M. Recent progress in the chemical reduction of graphene oxide by green reductants–A Mini review. Carbon Trends 2021, 5, 100120.
  20. Pareek, A.; Sravan, J.S.; Mohan, S.V. Exploring chemically reduced graphene oxide electrode for power generation in microbial fuel cell. Mater. Sci. Energy Technol. 2019, 2, 600–606.
  21. Berbeć, S.; Żołądek, S.; Wasilewski, P.; Jabłońska, A.; Kulesza, P.; Pałys, B. Electrochemically Reduced Graphene Oxide–Noble Metal Nanoparticles Nanohybrids for Sensitive Enzyme-Free Detection of Hydrogen Peroxide. Electrocatalysis 2020, 11, 215–225.
  22. Kong, B.-S.; Geng, J.; Jung, H.-T. Layer-by-layer assembly of graphene and gold nanoparticles by vacuum filtration and spontaneous reduction of gold ions. Chem. Commun. 2009, 16, 2174–2176.
  23. Liu, G.; Xiong, Z.; Yang, L.; Shi, H.; Fang, D.; Wang, M.; Shao, P.; Luo, X. Electrochemical approach toward reduced graphene oxide-based electrodes for environmental applications: A review. Sci. Total Environ. 2021, 778, 146301.
  24. Pushkareva, I.; Pushkarev, A.; Kalinichenko, V.; Chumakov, R.; Soloviev, M.; Liang, Y.; Millet, P.; Grigoriev, S. Reduced Graphene Oxide-Supported Pt-Based Catalysts for PEM Fuel Cells with Enhanced Activity and Stability. Catalysts 2021, 11, 256.
  25. Hassan, H.M.A.; Abdelsayed, V.; Khder, A.E.R.S.; AbouZeid, K.M.; Terner, J.; El-Shall, M.S.; Al-Resayes, S.I.; El-Azhary, A.A. Microwave synthesis of graphene sheets supporting metal nanocrystals in aqueous and organic media. J. Mater. Chem. 2009, 19, 3832–3837.
  26. Shih, K.-Y.; Wei, J.-J.; Tsai, M.-C. One-Step Microwave-Assisted Synthesis of PtNiCo/rGO Electrocatalysts with High Electrochemical Performance for Direct Methanol Fuel Cells. Nanomaterials 2021, 11, 2206.
  27. Rosli, N.H.A.; Lau, K.S.; Winie, T.; Chin, S.X.; Chia, C.H. Microwave-assisted reduction of graphene oxide for an electrochemical supercapacitor: Structural and capacitance behavior. Mater. Chem. Phys. 2021, 262, 124274.
  28. Faraji, S.; Ani, F.N. Microwave-assisted synthesis of metal oxide/hydroxide composite electrodes for high power supercapacitors—A review. J. Power Sources 2014, 263, 338–360.
  29. Jiang, T.; Wang, X.; Tang, S.; Zhou, J.; Gu, C.; Tang, J. Seed-mediated synthesis and SERS performance of graphene oxide-wrapped Ag nanomushroom. Sci. Rep. 2017, 7, 9795.
  30. Wei, J.; Hu, Y.; Liang, Y.; Kong, B.; Zheng, Z.; Zhang, J.; Jiang, S.P.; Zhao, Y.; Wang, H. Graphene oxide/core–shell structured metal–organic framework nano-sandwiches and their derived cobalt/N-doped carbon nanosheets for oxygen reduction reactions. J. Mater. Chem. A 2017, 5, 10182–10189.
  31. Gao, Y.; Gu, J.; Li, L.; Zhao, W.; Li, Y. Synthesis of gold nanoshells through improved seed-mediated growth approach: Brust-like, in situ seed formation. Langmuir 2016, 32, 2251–2258.
  32. He, L.-L.; Song, P.; Feng, J.-J.; Fang, R.; Yu, D.-X.; Chen, J.-R.; Wang, A.-J. Porous dandelion-like palladium core-shell nanocrystals in-situ growth on reduced graphene oxide with improved electrocatalytic properties. Electrochim. Acta 2016, 200, 204–213.
  33. Sun, B.; Wu, J.; Cui, S.; Zhu, H.; An, W.; Fu, Q.; Shao, C.; Yao, A.; Chen, B.; Shi, D. In situ synthesis of graphene oxide/gold nanorods theranostic hybrids for efficient tumor computed tomography imaging and photothermal therapy. Nano Res. 2017, 10, 37–48.
  34. Zahed, M.A.; Barman, S.C.; Sharifuzzaman, M.; Xuan, X.; San Nah, J.; Park, J.Y. Ex Situ Synthesis of Hexagonal NiO Nanosheets and Carboxyl-Terminated Reduced Graphene Oxide Nanocomposite for Non-Enzymatic Electrochemical Detection of H2O2and Ascorbic Acid. J. Electrochem. Soc. 2018, 165, B840.
  35. Alaefour, I.; Shahgaldi, S.; Zhao, J.; Li, X. Synthesis and Ex-Situ characterizations of diamond-like carbon coatings for metallic bipolar plates in PEM fuel cells. Int. J. Hydrog. Energy 2021, 46, 11059–11070.
  36. Kakaei, K.; Rahnavardi, M. Synthesis of nitrogen-doped reduced graphene oxide and its decoration with high efficiency palladium nanoparticles for direct ethanol fuel cell. Renew. Energy 2021, 163, 1277–1286.
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