Pt-Co nano-alloy catalysts with hierarchical core-shell architectures for enhanced dual-function electrocatalytic water splitting

Introducing other non-precious metals and tailoring the structure to develop Pt-based alloy catalysts is a viable strategy to reduce Pt massive consumption, enhance Pt utilization, and improve the performance of electrocatalysts. In this study, a novel kind of Pt-Co nanoframe alloy catalyst with a hierarchical nanostructure and two distinct particle morphologies has been obtained by using a simple synthetic method. The unique multi-level core-shell structure imparts higher intrinsic activity and conductivity to the Pt-Co Core-shell Nano particles (Pt-Co CSNP), facilitating efficient charge transfer and enhancing both hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) activities. At a current density of 10 mA cm -2 , the Pt-Co CSNP demonstrates excellent electrocatalytic performance, exhibiting overpotentials of 14.7 mV for HER in 0.5 M H 2 SO 4 and 200 mV for OER in 1.0 M KOH, which is a significant improvement over the performance of numerous reported catalysts. According to the mass activity calculation, the Pt-Co CSNP exhibit mass activities of 5.55 and 3.17 A mg Pt -1 for HER and OER, respectively. These values are improved by a factor of 22 and 35 times compared with those of commercial electrodes (Pt/C 20 %, RuO 2 ) at the same overpotential. After 300 h of operation, the catalyst shows minimal performance degradation, making it one of the most effective catalysts for dual-function HER/OER catalysis.