Gold Nanoparticle/Multi‐walled Carbon Nanotube Hybrid as a Stable Catalyst for the Oxygen Reduction Reaction.

Abstract: A gold nanoparticle/multi‐walled carbon nanotube (Au/MWNTs) hybrid was prepared following the scalable one‐pot reduction of chloroauric acid with tetrakis(hydroxymethyl)chloride in the presence of MWNTs. TEM, XRD, FTIR, XPS, and thermogravimetric analyses indicate that gold nanoparticles (Au NPs, <italic>d</italic>≈2.9 nm) protected with the tris(hydroxymethyl)oxide (THPO) ligand were deposited on the MWNTs, where no Oswald ripening was observed for the Au NPs after 3000 voltammetric cycling. The Au/MWNTs hybrid with THPO ligand exhibits an impressive catalytic activity toward the oxygen reduction reaction (ORR), following a direct four‐electron mechanism in alkaline solution, and it also manifests excellent long‐term cycling durability and tolerance to the possible crossover methanol. This demonstrates prospective for the hybrid to serve as a stable ORR catalyst for direct methanol fuel cells. [ABSTRACT FROM AUTHOR]