Electrocatalytic Oxygen Reduction Performance of Silver Nanoparticle Decorated Electrochemically Exfoliated Graphene

Autor(es)

Lopes, Joao Henrique ^[1] ; Ye, Siyu ^[2] ; Gostick, Jeff T. ^[3] ; Barralet, Jake E. ^{[1, 4]} ; Merle, Geraldine ^[1]

Afiliação do(s) autor(es)

^[1] McGill Univ, Fac Dent, Montreal, PQ H3A 2B2 - Canada

^[2] Ballard Power Syst, Burnaby, BC V5J 5J8 - Canada

^[3] McGill Univ, Dept Chem Engn, Montreal, PQ H3A 0C5 - Canada

^[4] McGill Univ, Fac Med, Dept Surg, Montreal, PQ H3A 2B2 - Canada

• Tipo de documento: Artigo Científico
• Fonte: Langmuir; v. 31, n. 35, p. 9718-9727, SEP 8 2015.
• Citações Web of Science: 16

Resumo

We have developed a potentiostatic double-pulse technique for silver nanoparticle (Ag NP) deposition on graphene (GRn) with superior electronic and ionic conductivity. This approach yielded a two-dimensional electrocatalyst with a homogeneous Ag NP spatial distribution having remarkable performance in the oxygen reduction reaction (ORR). GRn sheets were reproducibly prepared by the electrochemical exfoliation of graphite (GRp) at high yield and purity with a low degree of oxidation. Polystyrenesulfonate added during exfoliation enhanced the stability of the GRn solution by preventing the restacking of the graphene sheets and increased its ionic conductivity. The potentiostatic double-pulse technique is generally used to electrodeposit Pt nanoparticles and remains challenging for silver metal that exhibits nucleation and growth potentials relatively close to each other. We judiciously exploited this narrow margin of potential, and for the first time we report Ag NP electrodeposited onto graphene with the subsequent ability to control both the density and the size of metallic nanoparticles. Considering the high activity along with the lower cost of Ag compared to Pt, these findings are highly relevant to the successful commercialization of fuel cells and other electrochemical energy devices. (AU)

• Processo FAPESP: 13/12376-5 - Formação óssea controlada por íons inorgânicos biologicamente ativos: investigação do papel e entrega controlada de íons relevantes a partir de biomateriais
• Beneficiário: João Henrique Lopes
• Modalidade de apoio: Bolsas no Exterior - Estágio de Pesquisa - Doutorado