The effect of a gas atmosphere on the formation of colloidal platinum nanoparticles in liquid phase synthesis

This article demonstrates how purging the reaction medium with argon, oxygen, or CO during the liquid-phase synthesis affects the transformation dynamics of the Pt(IV) into Pt(0) x as well as the morphology of the Pt/C obtained. The reaction media studied are typical for the polyol and formic acid synthesis methods. The real-time monitoring of the Pt(0) x formation in these systems has been studied by the potentiometric and colorimetric measurements. The nature of a gas has been shown to affect the size of the small Pt particles formed as well as their different spatial distribution over the carbon support surface. Therefore, a gas is supposed to provide an additional control over both the formation of colloidal Pt and the microstructure of the Pt/C obtained. Moreover, this study illustrates a novel approach to using a platinum indicator electrode for the estimation of the reaction system’s redox state during the synthesis of Pt nanoparticles. Graphical Abstract