Graphene-assisted synthesis of PdFe-embedded porous carbon nanofibers for efficient ethanol electrooxidation

The Pd-based nanomaterials with advanced structures have shown remarkable activity for direct alcohol fuel cells (DAFCs). However, the dissolution of Pd and alloyed base metals, as well as the instability of Ostwald ripening and the formation of the poisoning species in fuel cell operation environments could cause catalyst degradation, which still remains an issue. Herein we report a graphene-confined thermal conversion strategy to fabricate high stability PdFe-embedded porous carbon nanofibers (PdFe@G-CNFs) for ethanol electrooxidation. Benefiting from the unique porous carbon-encapsulated structure and highly alloyed small-sized PdFe component, the resultant samples exhibit excellent electrocatalytic activity and stability for ethanol electrooxidation in alkaline media. Especially, the Pd2Fe1@G-CNFs exhibits enhanced carbon monoxide tolerance and higher peak current density (1896 mA mg(-1)) than Pd@G-CNFs (860 mA mg(-1)) and Pd2Fe1@CNFs (1276 mA mg(-1)). This study provides a new insight into designing high-efficiency and stable Pd-based electrocatalysts for DAFCs. (c) 2018 Elsevier Ltd. All rights reserved.