Preparation and optical aborption spectra of AucorePtshell and PtcoreAushell colloidal nanoparticles in aqueous solution

Bimetallic gold and platinum particles of the Pt-Au and Au-Pt core-shell type are prepared using hydrogen reduction and radiolysis techniques. The optical absorption spectra are recorded and compared to various Au-Pt particles described in the literature. AucorePtshell particles catalyze the hydrogen reduction of silver ions to yield trimetallic particles.