Synthesis of Au@Pt Core-Shell Nanoparticles as Efficient Electrocatalyst for Methanol Electro-Oxidation.

Autor: Higareda A; Posgrado en Ciencia e Ingeniería de Materiales, Centro de Física Aplicada y Tecnología Avanzada, Universidad Nacional Autónoma de México, Boulevard Juriquilla 3001, Santiago de Querétaro 76230, Mexico., Kumar-Krishnan S; Cátedras CONACYT_Instituto de Física, Benemérita Universidad Autónoma de Puebla, Apdo. Postal J-48, Puebla 72570, Mexico., García-Ruiz AF; UPIICSA-COFAA, Instituto Politécnico Nacional, Te 950, Col. Granjas-México, Iztacalco, Ciudad de México 08400, Mexico., Maya-Cornejo J; Centro de Física Aplicada y Tecnología Avanzada, Universidad Nacional Autónoma de México, Boulevard Juriquilla 3001, Santiago de Querétaro 76230, Mexico., Lopez-Miranda JL; Centro de Física Aplicada y Tecnología Avanzada, Universidad Nacional Autónoma de México, Boulevard Juriquilla 3001, Santiago de Querétaro 76230, Mexico., Bahena D; Laboratorio Avanzado de Nanoscopía Electrónica (LANE), Centro de Investigación y de Estudios Avanzados del I.P.N., Av. Instituto Politécnico Nacional 2508 Col. San Pedro Zacatenco, Ciudad de México 07360, Mexico., Rosas G; Instituto de Investigaciones Metalúrgicas, UMSNH, edificio U, Ciudad Universitaria, Morelia Michoacán 58060, Mexico., Pérez R; Instituto de Ciencias Físicas, Universidad Nacional Autónoma de México (UNAM), Av. Universidad s/n, Cuernavaca, Morelos 62210, Mexico., Esparza R; Centro de Física Aplicada y Tecnología Avanzada, Universidad Nacional Autónoma de México, Boulevard Juriquilla 3001, Santiago de Querétaro 76230, Mexico.
Jazyk: angličtina
Zdroj: Nanomaterials (Basel, Switzerland) [Nanomaterials (Basel)] 2019 Nov 19; Vol. 9 (11). Date of Electronic Publication: 2019 Nov 19.
DOI: 10.3390/nano9111644
Abstrakt: Bimetallic Au@Pt nanoparticles (NPs) with Pt monolayer shell are of much interest for applications in heterogeneous catalysts because of enhanced catalytic activity and very low Pt-utilization. However, precisely controlled synthesis with uniform Pt-monolayers and stability on the AuNPs seeds remain elusive. Herein, we report the controlled deposition of Pt-monolayer onto uniform AuNPs seeds to obtain Au@Pt core-shell NPs and their Pt-coverage dependent electrocatalytic activity for methanol electro-oxidation. The atomic ratio between Au/Pt was effectively tuned by varying the precursor solution ratio in the reaction solution. The morphology and atomic structure of the Au@Pt NPs were analyzed by high-resolution scanning transmission electron microcopy (HR-STEM) and X-ray diffraction (XRD) techniques. The results demonstrated that the Au@Pt core-shell NPs with Pt-shell thickness (atomic ratio 1:2) exhibit higher electrocatalytic activity for methanol electro-oxidation reaction, whereas higher and lower Pt ratios showed less overall catalytic performance. Such higher catalytic performance of Au@Pt NPs (1:2) can be attributed to the weakened CO binding on the Pt/monolayers surface. Our present synthesis strategy and optimization of the catalytic activity of Au@Pt core-shell NPs catalysts provide promising approach to rationally design highly active catalysts with less Pt-usage for high performance electrocatalysts for applications in fuel cells.
Databáze: MEDLINE