Core-shell and heterostructured silver-nickel nanocatalysts fabricated by gamma-radiation induced synthesis for oxygen reduction in alkaline media
Artikel i vetenskaplig tidskrift, 2022

To reach commercial viability for fuel cells, one needs to develop active and robust Pt-free electrocatalysts. Silver has great potential to replace Pt as the catalyst for the oxygen reduction reaction (ORR) in alkaline media due to its low cost and superior stability. However, its catalytic activity needs to be improved. One possible solution is to fabricate bimetallic nanostructures, which demonstrate a bifunctional enhancement in the electrochemical performance. Here, two types of bimetallic silver-nickel nanocatalysts, core-shells (Ag@NiO) and heterostructures (Ag/Ni), are fabricated using gamma-radiation induced synthesis. The Ag@NiO nanoparticles consist of an amorphous, NiO layer as a shell and a facetted crystalline Ag particle as a core. Meanwhile, the Ag/Ni heterostructures comprise Ag particles decorated with Ni/Ni(oxy-hydro)-oxide clusters. Both materials demonstrate similar and increased alkaline ORR activity as compared to monometallic catalysts. It was revealed that the enhanced catalytic activity of the core-shells is mainly attributed to the electronic ligand effect. While in the Ag/Ni heterostructures, a lattice mismatch between the Ni-based clusters and Ag implies a significant lattice strain, which, in turn, is responsible for the increased activity of the catalyst. Also, the Ag/Ni samples exhibit good stability under operating conditions due to the existence of stable Ni3+ compounds on the surface.

Författare

Yi Yang

Kungliga Tekniska Högskolan (KTH)

Gerard Montserrat Siso

Chalmers, Fysik, Kemisk fysik

Björn Wickman

Chalmers, Fysik, Kemisk fysik

Pavel Anatolyevich Nikolaychuk

Tyumen State University

Inna L. Soroka

Kungliga Tekniska Högskolan (KTH)

Dalton Transactions

1477-9226 (ISSN) 1477-9234 (eISSN)

Vol. 51 9 3604-3615

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Stiftelsen för Strategisk forskning (SSF) (EM16-0060), 2018-01-16 -- 2022-12-31.

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Vetenskapsrådet (VR) (2018-03927), 2019-01-01 -- 2022-12-31.

Ämneskategorier

Oorganisk kemi

Annan kemiteknik

Annan kemi

DOI

10.1039/d1dt03897d

PubMed

35147619

Mer information

Senast uppdaterat

2022-03-03