Facile synthesis of highly active and durable PdM/C (M = Fe, Mn) nanocatalysts for the oxygen reduction reaction in an alkaline medium

Author(s)

Holade, Yaovi ^{[1, 2, 3]} ; da Silva, Rodrigo G. ^{[1, 4]} ; Servat, Karine ^[1] ; Napporn, Teko W. ^[1] ; Canaff, Christine ^[1] ; de Andrade, Adalgisa R. ^[4] ; Kokoh, Kouakou B. ^[1]

Affiliation

^[1] Univ Poitiers, CNRS, UMR 7285, 4 Rue Michel Brunet, B27, TSA 51106, F-86073 Poitiers 09 - France

^[2] Univ Utah, Dept Chem, 315 S 1400 E Room 2020, Salt Lake City, UT 84112 - USA

^[3] Univ Utah, Dept Mat Sci & Engn, 315 S 1400 E Room 2020, Salt Lake City, UT 84112 - USA

^[4] Univ Sao Paulo, Dept Quim, Fac Filosofia Ciencias & Letras Ribeirao Preto, Ave Bandeirantes 3900, BR-14040901 Sao Paulo - Brazil

• Document type: Journal article
• Source: JOURNAL OF MATERIALS CHEMISTRY A; v. 4, n. 21, p. 8337-8349, JUN 7 2016.
• Web of Science Citations: 22

Abstract

The efficient design of highly active and durable materials towards the ultimate goal of improving kinetics of the oxygen reduction reaction (ORR), which allow enhanced performance in solid alkaline membrane fuel cells (SAMFCs), remains elusive. Seminal studies have shown that by alloying a noble metal such as palladium to a transition metal, it is possible to tune the electronic and/or bifunctional properties enabling substantial ORR performance to be achieved, thereby designing a costly catalyst. Herein, we address and discuss new findings from deeper ORR investigations at palladium-based nanostructures in an alkaline medium. We exploited and manipulated the straightforward and fast synthesis method, the so-called ``Bromide Anion Exchange{''}, to prepare surfactant-free PdM/C (M = Fe, Mn) nanocatalysts exhibiting unprecedented activity and stability towards ORR. PdFe/C from bromide anion exchange (BAE) enables 40- and 4-fold enhancement in terms of exchange current density and kinetic current density and ca. 100 mV gains compared to the polyot microwave-assisted method. After 20 000 cycles of accelerated potential cycling test (APCT), our findings indicate that the present PdM/C bimetallics outperform, to the best of our knowledge, most of the data reported for ORR in alkaline media for Pd-based transition metals. The improved catalytic performances are assigned to the absence of any organic contaminants or protective ligands on their surface and their relatively heterogeneous character comprising nanoalloys and nanowire oxides. (AU)

• FAPESP's process: 13/25632-0 - Physical characterization and DAFC performance of core@shell nanocatalysts in alkaline media
• Grantee: Rodrigo Garcia da Silva
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate