Green Chemical Synthesis of Copper Nanoparticles − A Comparative Study with Chemical Reduction and Electrolytic Methods

Abstract

INTRODUCTIONNano technology represents one of the emerging areas of modern science and technology. Nanoparticles are the materials which are in the 1-100 nm size domains and act as a bridge between atomic and bulk material. Metal nanoparticles have attracted great interest in modern chemistry and material research due to the large surface to volume ratio and quantum size effects [1][2][3]. They find applications in various fields such as photochemistry, nano electronics, optics and catalysis [4][5][6][7]. Metal nanoparticles were effective against pathogens. The unique properties of metal nanoparticles found to be influenced by the particle size, the organization of the nanoparticle crystal lattice and the chemical nature of the environment surrounding the nanoparticles [8,9]. Metal nanoparticles can be prepared by physical and chemical methods. The physical methods include subdivision of bulk metals, by crushing or pulverization of bulk metal, arc discharge between metal electrodes and so on. The chemical methods include the reduction of metal ions to form atoms followed by aggregation of atoms [10][11][12]. The chemical reductants involve NaBH4, alcohol, LiAlH4 molecular hydrogen hydrazine etc. Green method is an eco-friendly method for the production of nanoparticles, where plant systems are used for the synthesis of nanoparticles [13][14][15][16]. In order to prevent the agglomeration of nanoparticles and produce metal nanoparticles with a narrow size distribution, capping agents are important. Copper nanoparticles perform a key role in catalysis, antimicrobial fields and electronics. Copper nanoparticles were synthesized by various methods and their efficiencies were compared. Green Chemical approach which used citrus lemon fruit extract both as the reduction and capping agent is found to be most efficient and economical method for the synthesis of copper nanoparticles.