STEM-EDS Characterization of Platinum-Modified Nickel Nanoparticles

Nickel nanoparticles (Ni NPs) are quite interesting because they exhibit high catalytic activity, high selectivity and high efficiency in fuel cells [1, 2]. However the coke-formation takes place in these NPs involving chemical reactions. For instance the CO2 reforming of methane gas in the presence of Ni NPs leads to the formation of coke containing predominantly the carbon nanotubes (CNTs) [3]. Coke formation is detrimental to the efficiency of chemical reactions and hence results in the deactivation of catalysts and blockage of tubular reactor. This translates to higher amount of energy usage which is both costly as well as is not conducive to environment. Surface modification of Ni NPs with noble-metals not only reduces such coke formation but it also enhances their catalytic activity. In regards to the synthesis of bimetallic NPs, the approach of using surface organometallic chemistry (SOMC) method is both versatile as well as low-cost. However the success of SOMC method to produce uniform size and composition bimetallic NPs can be judged only after their successful characterization with an elaborate technique. Moreover the real space imaging and characterization of NPs is vital to understanding their structure-property relationships and transmission electron microscopy (TEM) helps enormously in the determination of such relationships [4].