| Different noble metal nanomaterials and their alloys present excellent tunable optical,electrical and catalytic properties with novel applications in the domains of optoelectronics,biosensor and molecular detection,etc.Studying the nucleation and growth process is still the key to prepare nanomaterials with specific structure and functional characteristics.With the development of shape-controlled synthesis as well as in situ and time resolved characterization techniques,the fundamental principles of nanomaterial growth can be observed in detail.Different results and curious phenomena give rise to further understand the classical nanoparticle growth.Nevertheless,the harsh synthesis conditions,such as high temperature,and tedious procedures,obstruct the real-timely monitoring of the unpredictable growth evolution.In this thesis,a facile one-pot wet-chemical method was suggested to prepare Au,Ag and their alloy nanostructures at room temperature.The mild condition and slow reaction process create a real-time path to monitor the evolution of these metallic nanostructures.The main research works were carried out as follows:(1)Monodispersed Au NPs were prepared in alkaline solution through the reduction of D-glucose in the presence of Au precursor and cetyltrimethylammoniun bromide(CTAB).Facile in-situ UV–vis and DLS techniques,accompanied by TEM,were used to investigate the growth mechanism of Au NPs.(2)Ag NPs and NWs were synthesized by the similar one-pot method without external templates or rigorous conditions.UV–vis,TEM and HRTEM were used to deeply understand the oriented-attachment mechanism of Ag NWs.(3)Au-Ag alloy NPs were produced using the mixing solution of Au and Ag precursors.The growth process was studied,and the results can offer a control route and deep insights on the growth mechanism of noble metal nanostructures. |
