Preparation of supported mono- and bimetallic nanoparticles by Supercritical Fluid Reactive Deposition (SFRD)

点击翻译按钮获取中文摘要

Due to unique properties and enhanced catalytic activities compared to conventional catalysts, nanoparticles and nanoalloys have been attracting increasing attention in catalytic applications. So far, mono- and bi-metallic nanoparticles were usually prepared by using conventional wet impregnation techniques that are associated with a few drawbacks such as poor control of the obtained product properties. In opposite thereto, the SFRD technique enables an alternative and promising method for the preparation of mono- and bimetallic nanoparticles, since it provides to control the particle size and distribution, homogeneity and concentration. The single component SFRD process consists of three steps that are: the dissolution of a precursor in scCO2, adsorption or sorption of the precursor onto support and the conversion of the adsorbed precursor to its metal form. Two approaches naturally arise in order to synthesize bimetallic nanoparticles using SFRD, which are simultaneous and sequential deposition. Therefore, within the proposed project, various mono- and bimetallic nanoparticles will be deposited on different supports. Similar to single component SFRD, in simultaneous SFRD the adsorption of precursor(s) on the support in the presence of scCO2 is of crucial importance and will be investigated applying experimental and theoretical approaches. Thus, the objectives of this proposed project are to prepare supported mono- and bimetallic nanoparticles via SFRD and to investigate the influence of precursor and substrate properties, adsorption behavior and reduction method on metal loading, particle size and distribution.