Research On Biosynthesis Of Nanomaterials And Their Applications

In recent years, nano-materials been used in metallurgical, chemical, defense, electronics, life sciences, aerospace, medical and other research areas. Nano-materials can be synthesized using traditional physical and chemical methods. A large number of chemicals have to be involved during the synthesis process, which can pose environmental risks to our environment. Therefore, it is particularly important for us to find a green and eco-environment friendly synthesis method.Biosynthesis has been proposed and applied widely in the field of nano science. Fungi, bacteria, plants and their extracts, animal tissue in nature have been used to synthesize nano-materials. In this paper, the synthetic methods to prepare gold nanoparticles and silver nanoparticles using jujube?shaddock peel and Chenopodium aristatum extract were developed. The main content of the thesis is as follows:(1) Fresh jujube and Chenopodium aristatum extract was used to reduce AgNO3 to obtained silver nanoparticles. The reaction process and the optimal reaction conditions were discussed in different concentrations of silver nitrate, temperature and pH. A variety of instruments were used to characterize the shape of silver nanoparticles. Moreover, the antibacterial and catalytic properties of the prepared nanoparticles were evaluated.(2)Fresh shaddock extract was used to reduce HAuCl4·4H2O to obtained gold nanoparticles. The reaction process and the optimal reaction conditions were discussed in different concentrations of silver nitrate, temperature and pH, and we used a variety of instruments to characterize the shape of gold nanoparticles. The antibacterial and catalytic properties were evaluated.In summary, the jujube ? shaddock peel and Chenopodium aristatum are widespread in nature, and they are inexpensive and easy to be obtained. The particles also have high chemical stability.