Synthesis Characterization and Applications of Colloidal Supported Metal Nanoparticles

Nanocatalysts show excellent catalytic activity because of their immense surface-to-volume ratio. In homogeneous nanocatalysis, the catalyst remains in the same phase as the reactants and products. Traditionally available homogeneous nanocatalysts include colloidal suspensions of transition metal nanoparticles. In heterogeneous nanocatalysis, the catalyst and the reactants are in different phases. Traditionally available heterogeneous nanocatalysts include metal nanoparticles adsorbed onto bulk supports such as silica, alumina, carbon etc. The main advantage associated with homogeneous nanocatalysts is that they have high selectivities compared to heterogeneous nanocatalysts. The main disadvantages associated with homogeneous nanocatalysts include poor thermal stability, metal contamination and difficulty recovering the catalyst. The heterogeneous nanocatalysts on the other hand have good thermal stabilities and good catalyst recoveries. We focused on synthesizing a new type of catalyst that we termed as colloidal supported metal nanoparticles (CSMNs). The CSMNs act as an intermediate class of nanocatalysts that have properties associated with both homogeneous and heterogeneous nanocatalysts. The synthesized CSMNs are characterized using TEM and EDS. The CSMNs are used as nanocatalysts for the Suzuki and Heck cross-coupling reactions. The kinetics of these reactions is monitored using high performance liquid chromatography (HPLC). The catalytic activity, stability and the recycling potential of the CSMNs is investigated in our study.