New Approach to Fully Ordered fct-FePt Nanoparticles for Much Enhanced Electrocatalysis in Acid

• Published in: Nano letters Vol. 15; no. 4; pp. 2468 - 2473
• Main Authors: Li, Qing, Wu, Liheng, Wu, Gang, Su, Dong, Lv, Haifeng, Zhang, Sen, Zhu, Wenlei, Casimir, Anix, Zhu, Huiyuan, Mendoza-Garcia, Adriana, Sun, Shouheng
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 08-04-2015
• Subjects: Catalysts; Electrocatalysis; Ferrous alloys; Hydrogen evolution; Intermetallics; Iron compounds; Nanoparticles; Reduction; hydrogen evolution; nanoparticles; electrocatalysis; face-centered tetragonal structure; oxygen reduction
• ISSN: 1530-6984; 1530-6992
• DOI: 10.1021/acs.nanolett.5b00320

Fully ordered face-centered tetragonal (fct) FePt nanoparticles (NPs) are synthesized by thermal annealing of the MgO-coated dumbbell-like FePt-Fe3O4 NPs followed by acid washing to remove MgO. These fct-FePt NPs show strong ferromagnetism with room temperature coercivity reaching 33 kOe. They serve as a robust electrocatalyst for the oxygen reduction reaction (ORR) in 0.1 M HClO4 and hydrogen evolution reaction (HER) in 0.5 M H2SO4 with much enhanced activity (the most active fct-structured alloy NP catalyst ever reported) and stability (no obvious Fe loss and NP degradation after 20 000 cycles between 0.6 and 1.0 V (vs RHE)). Our work demonstrates a reliable approach to FePt NPs with much improved fct-ordering and catalytic efficiency for ORR and HER.