Synthesis and Characterisation of Shape-Controlled Platinum Nanoparticles

Abstract

Tetra hexahedral platinum nanoparticles are electrochemically synthesized using square wave potential technique on a polished glassy carbon electrode. At the same time, platinum nanosphere and multipod are synthesized using the chemical method. The as-prepared nanoparticles are characterized by High-resolution Transmission electron microscopy (HR-TEM). Thereafter, the catalyst is subjected to potential cycling in 0.5 M H2SO4 and is tested for its possible activity towards oxygen reduction reaction (ORR). The particle size is found to be in the order of THH > Multipod > nanosphere and the ORR specific activity is in the order of multipod > nanosphere > THH. Since the size of the THH Pt nanoparticles are very large, the surface to volume ratio is very less which leads to less number of active sites. On the other hand, multipods contain less number anion (HSO4−) adsorption sites than nanosphere and therefore have more number of oxygen adsorption sites and high specific activity towards ORR.