Alkali Cation Effect During the Oscillatory Electroreduction of H2O2 on Pt

Author(s)

da Silva, Kaline N. ^[1] ; Nagao, Raphael ^[2] ; Sitta, Elton ^[1]

Affiliation

^[1] Univ Fed Sao Carlos, Dept Quim, BR-13565905 Sao Carlos, SP - Brazil

^[2] Univ Estadual Campinas, Inst Quim, BR-13083970 Campinas, SP - Brazil

• Document type: Journal article
• Source: CHEMISTRYSELECT; v. 2, n. 35, p. 11713-11716, DEC 11 2017.
• Web of Science Citations: 0

Abstract

Hydrogen Peroxide Reduction Reaction (HPRR) catalyzed by Pt was studied in alkaline media and the effect of alkali cations were analyzed by the changes on dynamic instabilities presented by this system under high ohmic drop conditions. The origin of these instabilities is the competition between OH2- electroreduction and hydrogen adsorption on Pt surfaces, the latter being the first step for hydrogen evolution reaction (HER). Both HER and hydrogen adsorption are cation-dependent which suggests that noncovalent interactions are able to stabilize the water molecules favoring the Pt-H formation. Thus, in an interphase, in which the noncovalent interactions are more effective, HPRR will proceed as an indirect poisoned system, reflecting on slow frequency oscillations (omega), for instance omega(LiOH) < omega(NaOH) < omega(KOH) for several H2O2 concentrations. (AU)

• FAPESP's process: 17/00089-2 - Multi-user equipament approved in grant 16/01817-9: ellipso-microscopy for surface imaging
• Grantee: Raphael Nagao de Sousa
• Support type: Multi-user Equipment Program
• FAPESP's process: 16/01817-9 - Design and control of self-organized electrochemical patterns
• Grantee: Raphael Nagao de Sousa
• Support type: Research Grants - Young Investigators Grants
• FAPESP's process: 13/07296-2 - CDMF - Center for the Development of Functional Materials
• Grantee: Elson Longo da Silva
• Support type: Research Grants - Research, Innovation and Dissemination Centers - RIDC
• FAPESP's process: 16/14758-0 - Instabilities in electrocatalysis: complex kinetics catalyzed by model PT surfaces
• Grantee: Kaline Nascimento da Silva
• Support type: Scholarships in Brazil - Master
• FAPESP's process: 16/22262-5 - Design and control of self-organized electrochemical patterns
• Grantee: Raphael Nagao de Sousa
• Support type: Scholarships in Brazil - Young Researchers
• FAPESP's process: 14/23916-3 - Instabilities in electrocatalysis: complex kinetics catalyzed by model Pt surfaces, Au and microelectrodes
• Grantee: Elton Fabiano Sitta
• Support type: Regular Research Grants