In situ FTIR insights into the electrooxidation mechanism of glucose as a function of the surface facets of Cu2O-based electrocatalytic sensors

Author(s)

Dourado, Andre H. B. ^[1] ; da Silva, Anderson G. M. ^[1] ; Pastrian, Fabian A. C. ^[1] ; Munhos, Renan L. ^[1] ; de Lima Batista, Ana P. ^[1] ; de Oliveira-Filho, Antonio G. S. ^[2] ; Quiroz, Jhon ^[1] ; de Oliveira, Daniela C. ^[3] ; Camargo, Pedro H. C. ^[1] ; Cordoba de Torresi, Susana I. ^[1]

Affiliation

^[1] Univ Sao Paulo, Inst Quim, Dept Quim Fundamental, Ave Prof Lineu Prestes 748, BR-05508000 Sao Paulo, SP - Brazil

^[2] Univ Sao Paulo, Fac Filosofia Ciencias & Letras Ribeirao Preto, Dept Quim, BR-14040901 Ribeirao Preto, SP - Brazil

^[3] Ctr Nacl Pesquisa Energia & Mat, Lab Nacl Luz Sincrotron, Campinas, SP - Brazil

• Document type: Journal article
• Source: JOURNAL OF CATALYSIS; v. 375, p. 95-103, JUL 2019.
• Web of Science Citations: 1

Abstract

We focus herein on understanding how the oxidation mechanism of glucose may be affected by the nature of the surface facets of Cu2O-based electrocatalytic sensors. To this end, we performed a series of in situ FTIR spectroelectrochemical experiments and DFT simulations by employing Cu2O cubes and octahedra as electrocatalytic sensors for glucose and other interferents. Interestingly, our in situ results demonstrated that the glucose oxidation mechanism displayed shape-dependent behavior, indicating that the glucose molecule can selectively adsorb on the Cu2O [1 0 0] facets relative to ascorbate and urate interferents in a process that probably occurs without the need for an external potential. However, when the same reaction was performed in the presence of Cu2O octahedra ([1 1 1] facets), the reaction was not selective, and the final product remained on the surface, blocking the sites for further glucose oxidation and leading to significantly lower electrocatalytic activities. Surprisingly, no bands related to the formation of Cu3+ species were detected, indicating that Cu3+ species do not participate in the reaction mechanism. This is very important because these species have been assumed to be the catalytically active sites for glucose oxidation. We believe that the results presented herein provide new insights into different aspects of the oxidation of carbohydrates and may inspire a deeper mechanistic investigation of other semiconductor materials and the development of optimized electrocatalysts. (C) 2019 Elsevier Inc. All rights reserved. (AU)

• FAPESP's process: 15/22203-6 - N-Heterocyclic Carbene Based Compounds in CO2 Activation: A Computational Approach
• Grantee: Ana Paula de Lima Batista
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• 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: 17/12407-9 - Hybrid nanostructures of transition metal oxides and conducting polymers for various applications
• Grantee: Anderson Gabriel Marques da Silva
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 15/11714-0 - Reactivity, transformation, fixation, and spectroscopy of systems involving CO2
• Grantee: Antonio Gustavo Sampaio de Oliveira Filho
• Support Opportunities: Regular Research Grants
• FAPESP's process: 13/25592-8 - Study of L-cysteine and L-cystine adsorption on platinum electrodes
• Grantee: André Henrique Baraldi Dourado
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)