Gold-rhodium nanoflowers for the plasmon enhanced ethanol electrooxidation under visible light for tuning the activity and selectivity

Author(s)

Rodrigues, Maria P. S. ; Dourado, Andre H. B. ; Krischer, Katharina ; Torresi, Susana I. Cordoba

• Document type: Journal article
• Source: Electrochimica Acta; v. 420, p. 9-pg., 2022-07-10.

Abstract

Direct ethanol fuel cells (DEFCs) are a promising power source, but the low selectivity to ethanol complete oxidation is still challenging. The localized surface plasmon resonance (LSPR) excitation has been reported to accelerate and drive several chemical reactions, including the ethanol oxidation reaction (EOR), coming as a strategy to improve catalysts performance. Nonetheless, metallic nanoparticles (NPs) that present the LSPR excitation in the visible range are known for leading to the incomplete oxidation of ethanol. Thus, we report here the application of gold-rhodium nanoflowers (Au@Rh NFs) towards the plasmon-enhanced EOR. These hybrid materials consist of a Au spherical nucleus covered by Rh branches shell, combining plasmonic and catalytic properties. Firstly, the Au@Rh NFs metallic ratio was investigated in dark conditions to obtain an optimal catalyst. Experiments were also performed under light irradiation. Our data demonstrated an improvement of 352% in current density and 36% in selectivity to complete ethanol oxidation under 533 nm laser incidence. Moreover, the current density showed a linear increase with the laser power density, indicating a photochemical effect and thus enhancement due to the LSPR properties. (AU)

• FAPESP's process: 21/00675-4 - Tying up materials for electrochemical energy storage and catalysis
• Grantee: Roberto Manuel Torresi
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 19/22505-3 - Investigation of plasmon enhanced ethanol electro-oxidation by AuRh catalyst: in situ and theoretical studies
• Grantee: Maria Paula de Souza Rodrigues
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate (Direct)
• FAPESP's process: 15/26308-7 - Optimization of the physicochemical properties of nano -structured materials for applications in molecular recognition, catalysis and energy conversion/storage
• Grantee: Roberto Manuel Torresi
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 18/16846-0 - Metal oxide nanowires decorated with gold nanoparticles for heterogeneous catalysis application
• Grantee: Maria Paula de Souza Rodrigues
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)