Paper ID: 1810535 Biosynthesis Of Copper Oxide Nanoparticles Using Camellia Sinensis Plant Powder Suriani Ibrahim 1, a *, Nurul Zariyah Jakaria@Zakaria 1,b, Shaifulazuar Rozali 1,c, Nik Nazri Nik Ghazali 1,d Mohd Sayuti Ab Karim 1,e and Mohd Faizul Mohd Sabri 1,f 1 Department of Mechanical Engineering, Faculty of Engineering, University of Malaya, 50603, MALAYSIA a sue_83@um.edu.my*, b n.zariah@gmail.com, c azuar@um.edu.my, d nik_nazri@um.edu.my, e mdsayuti@um.edu.my, f faizul@um.edu.my Abstract In this study, copper oxide nanoparticles were prepared by green approach using solution cast method. The mixture of green tea aqueous acts as a bio-reducing agent and copper nitrate is used as metal sources. The copper ions (Cu 2+ ) were reduced by polyphenol in green tea aqueous extract to form copper oxide nanoparticles. The FTIR spectra shown C-H peak represent polyphenol chemical bonding in green tea aqueous solution. As the weight of tea increases, the content of polyphenol in green tea also increases. The structure and morphology of the synthesized copper oxide nanoparticles were characterized using Field Emission Scanning Electron Microscopy (FESEM) and X-Ray diffraction (XRD). The size of the particles was found to be in the range of 100-200 nm. The formation rate of copper oxide nanoparticles is higher as the concentration of polyphenols increases. The optimum copper oxide nanoparticles with the smallest particles size was produced with the amount of 20 gram of green tea. Keywords: biosynthesis; bio-reducing agent; tea powder; copper oxides; nanomaterials 1 Introduction Copper oxide nanoparticles (CuO NPs) are widely used in various industrial applications including semiconductor devices, sensor, medicine, solar energy and catalyst. The properties of these copper nanoparticles are mostly dependent to the material size, morphology, and the specific surface area of the material, which strongly depend on the preparation method [1]. Smaller size and great porosity that exist in the nanoparticles are capable of performing a higher reaction yield. The usage of copper oxide nanoparticles in various applications has led to numerous studies of different synthesis method for copper nanoparticles [2-3]. In achieving a more convenient and less toxic disposal, eco-friendly approach is becoming favourable. The common synthesis procedure will yield to toxic chemical and high in cost [4]. Sometimes, the chemical by-product itself will drain into the soil and water that results in contamination that often leads to mutagens and serious health hazards. 1
Biosynthesis of nanoparticles by plant has currently received more attentions as it is a suitable alternative compared to chemical and physical methods. Previously, there are multiple studies that have been done on synthesis of the copper oxide nanoparticles by using different plant extract such as from Carica Papaya, Azadirachta indica (Indian Lilac), Hibiscus rosa-sinensis (Chinese hibiscus), Murraya koenigii (Curry Tree), Moringa oleifera (Drumstick Tree) and Tamarindus indica (Tamarind tree) [5]. The extract from the plants may act as reducing and capping agent for the nanoparticles synthesis. Different parts of plants such as the leaves, stems, seeds and fruits could be used in the synthesis as the plants exhibit combinations of metabolites [6]. Terpenoids, polyphenols, sugars, alkaloids, phenolic acids and proteins play an important role as the reducing agent in the synthesis [7]. For example, the polyphenolic compounds could release reactive hydrogen atoms that could reduce the metal ions to form nanoparticles. Thus, in this study, an eco-friendly approach of copper oxide nanoparticle is developed by using plant extract of tea extract aqueous (Camellia Sinensis). Afterwards, the CuO NPs were tested for the present of ions metal after the characterization test. Besides that, canesis tea has a higher polyphenols contents compared to others fruits like apples [8]. 2 Methodology 2.1 Materials The main material used in this research is the tea powder from plant Camellia sinensis obtained from a local store. 2.2 Preparation of Tea Extract The tea extract solutions were prepared by adding 20g, 30g and 40g of the green tea powder into the beaker followed by 200 ml of deionized water. The solution was mixed at 350 rpm for about 2 hours. After that, the samples were left for a while to allow the water and the tea to completely dissolve The samples obtained were filtered and then were kept at 4 o C for further use The copper nitrate solutions were prepared by using the same technique and stirred at 350 rpm. In this study, the concentration of the copper nitrate solution is 0.5 M. 2.3 Copper Oxide Nanoparticles The synthesis process starts with stirring and heating of the copper nitrate solution vigorously at 350 rpm until the copper nitrate were completely dissolved. Subsequently, 100 ml of 20 gram of tea extract solution was slowly added. The solution was heated at 90 o C and stirred for about one hour. The colour changes gradually from sea blue to brownish, which was indicating the formation of the copper oxide nanoparticles as showed in Figure 1. After one hour, the mixture was cooled at room temperature. The process was repeated but with different concentrations of tea extracts solution. The precipitates obtained 2
were filtered and rinsed with ethanol. Then, the process is continued by purification of the sample by rinsing the precipitates with distilled water. To remove the moisture from copper oxide nanoparticles, the particles were dried in a conventional oven at 90 o C for 5 hours. Figure 1 Colour changing during biosynthesis of copper oxide nanoparticles. 2.4 Characterization of Nanoparticles It is necessary to characterize the properties of the copper nanoparticles in order to understand the effect of experimental parameter. FESEM with 2kV was used to determined morphology of the nickel oxide nanoparticles. Energy Dispersive X-ray Spectrometry (EDX) is a microanalysis technique that is used to validate and confirm the existence of copper oxide element in the nanoparticles. 3 Results and Discussion 3.1 Morphology studies The physical properties of biosynthesized copper oxide nanoparticles can be observed by FESEM and the FESEM images were shown in Figure 2. The biosynthesized CuO NPs were spherical in shape. It shows that when higher the concentration of tea extract solutions used, the more the aggregation can be observed. Based on Figure 3, the mean diameter for the CuO NPs obtained were 391.43 nm, 243 nm, and 230.74 nm for CuO 20, CuO 30 and CuO 40 respectively. Although the synthesis of CuO 20 exhibits a larger average size, the nanoparticles are well dispersed and distributed compared to others. Figure 2: FESEM images for (a) CuO 20 (b) CuO 30 and (c) CuO 40 Figure 3: Copper Oxide Nanoparticles particle size distribution for (a) CuO 20 (b) CuO 30 and (c) CuO 40. The chemical compositions for all CuO NPs were illustrated in Table 1. It shows that copper and oxygen are present in the finished product. It also can be observed when the concentration of phenolic compound increases, the copper content in the sample will decrease. Table 1 Chemical composition for synthesized copper oxide nanoparticles 3
4 Conclusions Copper oxide nanoparticles were successfully synthesized using the biosynthesis method. Tea solution extract was used as a bio-reducing agent. Reduction of metal salt occurred due to the presence of phenol compound in the tea aqueous extract. The biosynthesized copper oxide nanoparticles have different sizes from the FESEM images with 391.43 nm, 243 nm and 230.74 nm for CuO 20, CuO 30 and CuO 40 of the tea aqueous extract. Acknowledgements This work was supported by the University of Malaya with Grant no. BK063-2016 and RF025A-2018. The authors also would like to express appreciation to Department of Mechanical Engineering, University of Malaya technical staffs for their assistance. References 1. Aparna, Y., Enkateswara Rao, K., & Subbarao, P. (2012). Synthesis and Characterization of CuO Nano Particles by Novel Sol Gel Method. International Conference On Environment Science And Biotechnology, 48. http://dx.doi.org/doi: 10.7763 2. Muhammad Imran Din, Rida Rehan. (2017) Synthesis, Characterization, and Applications of copper nanoparticles, Journal of Analytical Letters, 50: 50 62. 3. Suriani Ibrahim, Tawatchai Charinpanitkul, Eiry Kobatake et al (2016) Nanowires Nickel Oxide and Nanospherical Manganese Oxide Synthesized via Low Temperature Hydrothermal Technique for Hydrogen Peroxide Sensor, Journal of Chemistry, Article ID 9138961. 4. Krishna Gudikandula and Singara Charya Maringanti. (2016) Synthesis of silver nanoparticles by chemical and biological methods and their antimicrobial properties. Journal of Experimental Nanoscience 11: 714 721 5. Rajendran A, Siva E, Dhanraj C et al (2018) A Green and Facile Approach for the Synthesis Copper Oxide Nanoparticles Using Hibiscus rosa-sinensis Flower Extracts and It's Antibacterial Activities. Journal of Bioprocessing & Biotechniques, 8 : 1-4. 6. Palaniselvam Kuppusamy, Mashitah M.Yusoff Gaanty, Pragas Maniam et al (2016) Biosynthesis of metallic nanoparticles using plant derivatives and their new avenues in pharmacological applications An updated report. Saudi Pharmaceutical Journal, 24 : 473-484. 7. Nurul Amal Nadhirah Mohamad, Nur Afiqah Arham, Junaidah Jai et al (2014) Plant Extract as Reducing Agent in Synthesis of Metallic Nanoparticles: A Review. Advanced Materials Research 832 : 350-355 4
8. Claudine M., Augustin S., Christine M. et al (2004) Polyphenols: food sources and bioavailability, The American Journal of Clinical Nutrition. 79 : 727 747. 5