Nanoporous PdNi alloys as highly active and methanol-tolerant electrocatalysts towards oxygen reduction reaction†
A nanoporous PdNi (NP-PdNi) alloy with uniform structure dimension is easily fabricated by one-step mild dealloying of a PdNiAl precursor alloy. NP-PdNi consists of an interconnected nanoscaled network backbone and bicontinuous hollow channels in all three dimensions with a typical ligament size of around 5 nm. Electrochemical measurements indicated that the NP-PdNi alloy has superior electrocatalytic activity towards oxygen reduction reaction (ORR) with much higher specific and mass activities as well as higher methanol tolerance compared with Pt/C catalysts. Importantly, NP-PdNi suffers less loss of the ORR activity and the electrochemical surface area of metal upon 5000 potential cycles in acid solution than Pt/C, indicating a better catalytic durability. The NP-PdNi alloy holds great application potential as a cathode electrocatalyst in the fuel cell related technology with unique ORR performance, high structure stability, and easy preparation.