Co-Existence of Atomic Pt and CoPt Nanoclusters on Co/SnO_x Mix-Oxide Demonstrates an Ultra-High-Performance Oxygen Reduction Reaction Activity

Abstract

An effective approach for increasing the Noble metal-utilization by decorating the atomic Pt clusters (1 wt.%) on the CoO2@SnPd2 nanoparticle (denoted as CSPP) for oxygen reduction reaction (ORR) is demonstrated in this study. For the optimum case when the impregnation temperature for Co-crystal growth is 50 °C (denoted as CSPP-50), the CoPt nanoalloys and Pt-clusters decoration with multiple metal-to-metal oxide interfaces are formed. Such a nanocatalyst (NC) outperforms the commercial Johnson Matthey-Pt/C (J.M.-Pt/C; 20 wt.% Pt) catalyst by 78-folds with an outstanding mass activity (MA) of 4330 mA mgPt−1 at 0.85 V vs. RHE in an alkaline medium (0.1 M KOH). The results of physical structure inspections along with electrochemical analysis suggest that such a remarkable ORR performance is dominated by the potential synergism between the surface anchored Pt-clusters, CoPt-nanoalloys, and adjacent SnPd2 domain, where Pt-clusters offer ideal adsorption energy for O2 splitting and CoPt-nanoalloys along with SnPd2 domain boost the subsequent desorption of hydroxide ions (OH−).

Keywords

• oxygen reduction reaction
• fuel cells
• Pt-utilization
• mass activity
• potential synergism