Green Synthesis of Silver and Gold Nanoparticles from Local Sabah Tea Extract (Camellia Sinensis)

Metal nanoparticles such as silver and gold with a particle size between 1 to 100 nm can exhibit size-related properties that make it suitable in various applications such as sensors, catalysis, medical and others. For synthesis of metal nanoparticles, common techniques such as photo-catalytic reduction, solvothermal methods and reduction using chemicals not only found to be costly but also consume a significant usage of toxic and hazardous chemicals. Therefore, the need for a ‘greener’ approach that utilize eco-friendly materials (organisms like plants) and processes must be implemented in order to solve this issue. In this study, we aim to use a plant extract from local Sabah tea (Camellia Sinensis) as a reducing agent for synthesis of silver and gold nanoparticles. For the preparation of tea extract (Camellia Sinensis), water will be used as the solvent where thetea will be simply immersed and boiled in the water for 20 minutes. For synthesis of silver nanoparticles, the resulting tea extract will be directly added to silver nitrate and gold(III) chloride solution to allow the reduction of Ag(I) to Ag(0) and Au(III) to Au(0) to take place respectively. The successful synthesis of silver and gold nanoparticles will be observed based primarily on any physical colour changes. Future studies will involve the potential application of the synthesized metal nanoparticlesin catalytic applications such as degradation of 4-nitrophenol commonly found in industrial wastewater.