Cinnamon supported facile green reduction of graphene oxide, its dye elimination and antioxidant activities

Materials Letters ∎ (∎∎∎∎) ∎∎∎–∎∎∎

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Cinnamon supported facile green reduction of graphene oxide, its dye elimination and antioxidant activities D. Suresh a,n, Udayabhanu a, M.A. Pavan Kumar b, H. Nagabhushana c, S.C. Sharma d,e a

Department of Chemistry, Tumkur University, Tumkur 572103, India Department of Biochemistry, Tumkur University, Tumkur 572103, India c Centre for Advanced Materials, Tumkur University, Tumkur 572103, India d Chattisgarh Swami Vivekananda Technical University, Bhilai, Chattisgarh 493441, India e Department of Mechanical Engineering, Siddaganga Institute of Technology, Tumkur 572103, Karnataka, India b

art ic l e i nf o

a b s t r a c t

Article history: Received 16 September 2014 Accepted 7 March 2015

A simple and efficient method of reduction for the preparation of reduced graphene oxide (rGO) from graphene oxide (GO) using Cinnamon (Cinnamomum zeylanicum) extract is reported. The reduction of GO was confirmed by XRD, TEM and UV–visible techniques. The rGO has shown to possess significantly high dye removal property of Malachite green (MG) and Methylene blue (MB) dyes in the absence of UV or Sun light. Further, it showed considerable antioxidant activity against scavenging of 1, 1-Diphenyl-2picrylhydrazyl (DPPH) free radicals. The study illustrates an environment friendly green method for the efficient reduction of GO. & 2015 Published by Elsevier B.V.

Keywords: Carbon materials Cinnamon Green reduction Graphene oxide Dye elimination

1. Introduction Graphene, a wonder material is found to possess extremely superior electronic, optical, mechanical and catalytic properties [1,2]. Such characters have opened up new vista for materials science. Due its unique properties, graphene has been widely used for various applications such as biosensors [3], conversion or charge storage [4], drug delivery [5], composite materials [6], supercapacitor electrode materials [7] etc. In order to reap the benefits of these applications, graphene production in large scale is a high necessity. Various methods such as chemical vapor deposition, epitaxial growth, electric arc discharge and graphene oxide (GO) reduction in solution have been reported for the preparation of graphene [7,8]. However, preparation of graphene from solution based reduction of GO has been very popular due to its bulk scalability and cost effectiveness. But, major drawback of the chemical reduction method is due to the utilization of hazardous chemical reductants (hydrazines, borohydrides and hydroqinones) in the process [9,10]. Therefore, there is an immediate need to develop alternate methods. Several attempts have been made to achieve the reduction of graphene through green approaches [11–13]. The bark of Cinnamon (Cinnamomum zeylanicum), a common spice used in various countries has been extensively used in traditional medicine for treating

n

Corresponding author. Tel: þ 91 9886465964. E-mail address: [email protected] (D. Suresh).

various ailments. It was proved to possess antiparasitic, antimicrobial, antioxidant and free radical scavenging activities. It was also found to reduce blood glucose, serum cholesterol and blood pressure [14,15]. These medicinal properties could be due to the presence of potentially antioxidant and health beneficial compounds such as Cinnamaldehyde, Eugenol and their derivatives [16]. These antioxidants may act as good reducing agents for the reduction of GO. Therefore, an attempt has been made for the first time to assess the potency of Cinnamon extract towards the reduction of GO.

2. Experimental Graphite flakes were procured from Sigma Aldrich Company and all other chemicals (AR grade) from S. D. Fine Chemicals Company. Cinnamon was procured from local market. Preparation of Cinnamon extract: Powdered Cinnamon bark was mixed with double distilled water in the ratio of 1:10 and the extraction was carried out at 100 1C with a reflux arrangement for 5 h with constant stirring in a round bottomed flask. The extract was filtered, concentrated and dried. Preparation of GO: Graphite (5 g) and Sodium nitrate (2.5 g) were mixed with 120 mL of Sulfuric acid (95%) [17]. The mixture was stirred for 30 min in an ice bath followed by the addition of 15 g of Potassium permanganate with vigorous stirring and at temperature below 20 1C. The stirring was continued overnight and 150 mL of distilled water was slowly added. The reaction

http://dx.doi.org/10.1016/j.matlet.2015.03.035 0167-577X/& 2015 Published by Elsevier B.V.

Please cite this article as: Suresh D, et al. Cinnamon supported facile green reduction of graphene oxide, its dye elimination and antioxidant activities. Mater Lett (2015), http://dx.doi.org/10.1016/j.matlet.2015.03.035i

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temperature was rapidly increased to 98 1C and 50 mL of 30% H2O2 was added. The product was washed with 5% HCl, deionized water and dried [18]. Reduction of GO: 80 mg of GO was dispersed in 50 ml distilled water by sonication for a period of 40 min. The suspension was mixed with Cinnamon extract and refluxed for 45 min. The product was washed with distilled water, dried and stored. Characterization: GO and rGO were characterized using PXRD (Shimadzu-7000 X-ray diffractometer with monochromatized Cu-Kα radiation), a Thermo Scientific Evolution-220 UV–visible Spectrophotometer and TEM (TECNAIF-30). Dye elimination activity: Exactly 100 ml of the dye solutions were added with 20 mg of reduced graphene and stirred in dark [18]. Known volume of the slurry was drawn at specific intervals and absorbance was recorded for MB and MG (663 and 616 nm respectively). The percentage removal of the dye was determined using the relation % of elimination ¼

C i C f  100 Ci

where Ci and Cf are initial and final dye concentrations respectively. Antioxidant activity: 860 ml of test sample with various concentrations of rGO was mixed with 140 ml of 1 mM DPPH and incubated at 37 1C for 30 min [19]. The absorbance difference of the control and the rGO was measured at 520 nm and IC50 value was determined.

In X-ray diffraction pattern (Fig. 1), the appearance of 2θ intense peak at 261 corresponds to interlayer distance of about 0.34 nm for graphite. This peak was shifted to 101 in GO suggesting the enhancement in interlayer distance due to the formation of an array of functional groups resulting in lose stacking of the layers. The (002) reflection peak was absent in the diffraction pattern of rGO indicating the absolute exfoliation of the GO. Broad peak around 231 is due to the formation of few layers of rGO sheets. The band at 431 corresponded to the turbostratic band of disordered rGO. TEM studies (Fig. 2) clearly suggest the formation of transparent and exfoliated rGO due to the process of reduction with Cinnamon extract. The peak in UV–visible spectrum at 226 nm is attributed to the π–πn transition of CQC bonds in the case of GO (Fig. 3). However, this was completely absent in the spectrum of rGO due to restoration of graphitic structure in rGO after reduction. Peak at 280 nm may be ascribed to bioreduction of GO resulting in better restoration of π-electronic conjugated network structure. Dye elimination property of rGO was evaluated with MG and MB without exposure to either UV or Sunlight in the presence of 20 mg of rGO (Fig. 4). It suggests comprehensive removal of both the dyes in a span of 40 min. Fig. 5 illustrates antioxidant activity of prepared rGO. The results suggest that the concentration required for 50% inhibition of scavenging activity of DPPH free radical was found to be 2250 μg/ml. Therefore, the rGO exhibits considerable antioxidant activity by inhibiting the free radical scavenging activity of DPPH.

3. Results and discussion Graphene is a two-dimensional material comprising of a layer of bonded sp2 carbon atoms arranged in a hexagonal manner. Its discovery has revolutionized the materials science research and their applications. Two methods namely, bottom up and top down have been applied for the preparation of graphene. Here we have attempted top down method of preparation of graphene from graphite flakes. In view of its economical and environment friendly production, green method has been suggested in this study.

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Wavelength (nm) Fig. 3. UV–visible spectra of GO and rGO.

Please cite this article as: Suresh D, et al. Cinnamon supported facile green reduction of graphene oxide, its dye elimination and antioxidant activities. Mater Lett (2015), http://dx.doi.org/10.1016/j.matlet.2015.03.035i

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Fig. 4. Elimination of (a) Malachite green and (b) Methylene blue in the presence of rGO.

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Antioxidant activity of rGO has not been well studied. A recent study has established few-layer graphene is more active than monolayer graphene oxide, despite its lower surface area, which indicates that the primary scavenging sites are associated with the sp2-carbon network rather than oxygen-containing functional groups [20]. Our earlier studies [14,19] have indicated that rGO posess considerable antioxidant activity. Further studies in this direction are necessary. The dye elimination property of rGO is mainly due to vast surface area. A study investigated the role of GO on adsorption of methyl green dye from aqueous solution. It demonstrated that the elimination is due to the presence of oxygen containing functionalities such as carboxyl, epoxy, ketone, and hydroxyl groups on GO [21]. Our study unequivocally demonstrate the effective elimination of MG and MB due to adsorption on the surface of the rGO.

4. Conclusion In summary, we describe an ecofriendly, green and facile approach for the synthesis of rGO using very commonly available Cinnamon bark. Diffraction, imaging and spectroscopic techniques unequivocally demonstrate the efficient reduction and formation of few layered graphene from GO. The prepared rGO was proved to possess significantly high dye removal and antioxidant properties. The availability of Cinnamon, easier method of reduction makes it potentially attractive for the large scale synthesis of graphene and related materials.

[1] Novoselov KS, Geim AK, Morozov SV, Jiang D, Zhang Y, Dubonos SV, et al. Electric field effect in atomically thin carbon films. Science 2004;306:666–9. [2] Geim AK. Graphene: status and prospects. Science 2009;324:1530–4. [3] Shao Y, Wang J, Wu H, Liu J, Aksay IA, Lin Y. Graphene based electrochemical sensors and biosensors: a review. Electroanalysis 2010;22:1027–36. [4] Kou R, Shao Y, Wang D, Engelhard MH, Kwak JH, Wang J, et al. Enhanced activity and stability of Pt catalysts on functionalized graphene sheets for electrocatalytic oxygen reduction. Electrochem Commun 2009;11:954–7. [5] Ma X, Tao H, Yang K, Feng L, Cheng L, Shi X, et al. A functionalized graphene oxide-iron oxide nanocomposite for magnetically targeted drug delivery, photothermal therapy, and magnetic resonance imaging. Nano Res 2012;5:199–212. [6] Stankovich S, Dikin DA, Dommett GHB, Kohlhaas KM, Zimney EJ, Stach EA, et al. Graphene-based composite materials. Nature 2006;442:282–6. [7] Zanina H, Saitoa E, Ceragiolib HJ, Baranauskasb V, Corat EJ. Reduced graphene oxide and vertically aligned carbon nanotubes superhydrophilic films for supercapacitors devices. Mater Res Bull 2014;49:487–93. [8] Hsia B, Ferralis N, Senesky DG, Pisano AP, Carraro C, Maboudian R. Epitaxial graphene growth on 3C-SiC(111)/AlN(0001)/Si(100). Electrochem Solid-State Lett 2011;14:13–5. [9] Stankovich S, Dikin DA, Piner RD, Kohlhaas KA, Kleinhammes A, Jia Y, et al. Synthesis of graphene-based nano sheets via chemical reduction of exfoliated graphite oxide. Carbon 2007;45:1558–65. [10] Si Y, Samulski ET. Synthesis of water soluble graphene. Nano Lett 2008;8:1679–82. [11] Thakur Suman, Karak Niranjan. Green reduction of graphene oxide by aqueous phytoextracts. Carbon 2012;50:5331–9. [12] Zheng Bo Xiaorui Shuai, Mao Shun, Yang Huachao, Qian Jiajing, Chen Junhong, Yan Jianhua, et al. Green preparation of reduced graphene oxide for sensing and energy storage applications. Sci Rep 2014;4:4684. http://dx.doi.org/ 10.1038/srep04684. [13] Suresh D. Udayabhanu, Nagabhushana H, Sharma SC. , Clove extract mediated facile green reduction of graphene oxide, its dye elimination and antioxidant properties. Mater Lett 2015;142:4–6. [14] Priyanga Ranasinghe, Shehani Pigera, Sirimal Prema kumara GA, Priyadarshani Galappaththy, Godwin R Constantine, Prasad Katulanda. Medicinal properties of ‘true’ cinnamon (Cinnamomum zeylanicum): a systematic review. BMC Complement Altern Med 2013;13:275–375. [15] Sambaiah K, Srinivasan K. Effect of cumin, cinnamon, ginger, mustard and tamarind in induced hypercholesterolemic rats. Nahrung 1991;35:47–51. [16] Singh G, Maurya S, De Lampasona MP, Catalan CA. A comparison of chemical, antioxidant and antimicrobial studies of cinnamon leaf and bark volatile oils, oleoresins and their constituents. Food Chem Toxicol 2007;45:1650–61. [17] Hummers WS, Offeman RE. Preparation of graphitic oxide. J Am Chem Soc 1958;80:1339. [18] Suresh D, Nethravathi PC, Udayabhanu, Nagabhushana H, Sharma SC. Spinach assisted green reduction of graphene oxide and its antioxidant and dye absorption properties. Ceram Int 2015;41:4810–3. [19] Brand-Williams W. Use of free radical method to evaluate antioxidant activity. Food Sci Technol 1995;28:25–30. [20] Yang Qiu Zhongying Wang, Owens Alisa CE, Kulaots Indrek, Chen Yantao, Kane Agnes B, Robert H Hurt. Antioxidant chemistry of graphene-based materials and its role in oxidation protection technology. Nanoscale 2014;6:11744–55. [21] Sharma Ponchami, Das Manash R. Removal of a cationic dye from aqueous solution using graphene oxide nanosheets: investigation of adsorption parameters. Chem Eng Data 2013;58:151–8.

Please cite this article as: Suresh D, et al. Cinnamon supported facile green reduction of graphene oxide, its dye elimination and antioxidant activities. Mater Lett (2015), http://dx.doi.org/10.1016/j.matlet.2015.03.035i

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