Details

Autor(en) / Beteiligte

• Luo, Fang
• Roy, Aaron
• Silvioli, Luca
• Cullen, David A.
• Zitolo, Andrea
• Sougrati, Moulay Tahar
• Oguz, Ismail Can
• Mineva, Tzonka
• Teschner, Detre
• Wagner, Stephan
• Wen, Ju
• Dionigi, Fabio
• Kramm, Ulrike I.
• Rossmeisl, Jan
• Jaouen, Frédéric
• Strasser, Peter

Titel

P-block single-metal-site tin/nitrogen-doped carbon fuel cell cathode catalyst for oxygen reduction reaction

Ist Teil von

• Nature materials, 2020-11, Vol.19 (11), p.1215-1223

Ort / Verlag

London: Nature Publishing Group UK

Erscheinungsjahr

2020

Quelle

Nature_系列刊

Beschreibungen/Notizen

• This contribution reports the discovery and analysis of a p -block Sn-based catalyst for the electroreduction of molecular oxygen in acidic conditions at fuel cell cathodes; the catalyst is free of platinum-group metals and contains single-metal-atom actives sites coordinated by nitrogen. The prepared SnNC catalysts meet and exceed state-of-the-art FeNC catalysts in terms of intrinsic catalytic turn-over frequency and hydrogen–air fuel cell power density. The SnNC-NH 3 catalysts displayed a 40–50% higher current density than FeNC-NH 3 at cell voltages below 0.7 V. Additional benefits include a highly favourable selectivity for the four-electron reduction pathway and a Fenton-inactive character of Sn. A range of analytical techniques combined with density functional theory calculations indicate that stannic Sn( iv )N x single-metal sites with moderate oxygen chemisorption properties and low pyridinic N coordination numbers act as catalytically active moieties. The superior proton-exchange membrane fuel cell performance of SnNC cathode catalysts under realistic, hydrogen–air fuel cell conditions, particularly after NH 3 activation treatment, makes them a promising alternative to today’s state-of-the-art Fe-based catalysts. For oxygen reduction and hydrogen oxidation reactions, proton-exchange membrane fuel cells typically rely on precious-metal-based catalysts. A p -block single-metal-site tin/nitrogen-doped carbon is shown to exhibit promising electrocatalytic and fuel cell performance.