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Roychowdhury D, Veenu V, Ranjan C. Electronic Effect or Underpotentially Deposited Hydrogen? Insights into the effect of Pb on formic acid electro‐oxidation on Pt. ChemCatChem 2022. [DOI: 10.1002/cctc.202200115] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
| | - Veenu Veenu
- Indian Institute of Science Inorganic and Physical Chemistry INDIA
| | - Chinmoy Ranjan
- Indian Institute of Science Inorganic and Physical Chemistry CV Raman Ave 560012 Bangalore INDIA
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da Silva KN, Nagao R, Sitta E. Oscillatory ethylene glycol electrooxidation reaction on Pt in alkaline media: The effect of surface orientation. Electrochim Acta 2020. [DOI: 10.1016/j.electacta.2020.136986] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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3
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Calderón-Cárdenas A, Paredes-Salazar EA, Varela H. Apparent Activation Energy in Electrochemical Multistep Reactions: A Description via Sensitivities and Degrees of Rate Control. ACS Catal 2020. [DOI: 10.1021/acscatal.0c02359] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Alfredo Calderón-Cárdenas
- Instituto de Química de São Carlos, Universidade de São Paulo, São Carlos, CEP 13560-970 São Paulo, Brasil
- GIFBA, Universidad de Nariño, 52001 San Juan de Pasto-Nariño, Colombia
| | - Enrique A. Paredes-Salazar
- Instituto de Química de São Carlos, Universidade de São Paulo, São Carlos, CEP 13560-970 São Paulo, Brasil
| | - Hamilton Varela
- Instituto de Química de São Carlos, Universidade de São Paulo, São Carlos, CEP 13560-970 São Paulo, Brasil
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4
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Mechanistic aspects of the comparative oscillatory electrochemical oxidation of formic acid and methanol on platinum electrode. J Solid State Electrochem 2020. [DOI: 10.1007/s10008-020-04609-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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5
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da Silva KN, Sitta E. Tuning oscillatory time-series evolution by Pt(111)-OHad stabilization. J Solid State Electrochem 2020. [DOI: 10.1007/s10008-020-04557-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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6
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Fiori I, Melle G, Sitta E. Halide adsorption effect on methanol electro-oxidation reaction studied by dynamic instabilities. J Electroanal Chem (Lausanne) 2020. [DOI: 10.1016/j.jelechem.2019.113657] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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7
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Nogueira JA, Krischer K, Varela H. Coupled Dynamics of Anode and Cathode in Proton‐Exchange Membrane Fuel Cells. Chemphyschem 2019; 20:3081-3088. [DOI: 10.1002/cphc.201900531] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2019] [Revised: 07/18/2019] [Indexed: 11/09/2022]
Affiliation(s)
- Jéssica A. Nogueira
- Institute of Chemistry of São CarlosUniversity of São Paulo P.O. Box 780 13560-970 São Carlos, SP Brazil
| | - Katharina Krischer
- Department of PhysicsTechnical University of Munich James-Franck-Str. 1 D-85748 Garching Germany
| | - Hamilton Varela
- Institute of Chemistry of São CarlosUniversity of São Paulo P.O. Box 780 13560-970 São Carlos, SP Brazil
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Kitagaki BT, Pinto MR, Queiroz AC, Breitkreitz MC, Rossi F, Nagao R. Multivariate statistical analysis of chemical and electrochemical oscillators for an accurate frequency selection. Phys Chem Chem Phys 2019; 21:16423-16434. [PMID: 31144704 DOI: 10.1039/c9cp01998g] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The effect of experimental parameters on the frequency of chemical oscillators has been systematically studied since the first observations of clock reactions. The approach is mainly based on univariate changes in one specific parameter while others are kept constant. The frequency is then monitored and the effect of each parameter is discussed separately. This type of analysis, however, does not take into account the multiple interactions among the controllable parameters and the synergic responses on the oscillation frequency. We have carried out a multivariate statistical analysis of chemical (BZ-ferroin catalyzed reaction) and electrochemical (Cu/Cu2O cathodic deposition) oscillators and identified the contributions of the experimental parameters on frequency variations. The BZ reaction presented a strong dependence on the initial concentration of sodium bromate and temperature, resulting in a frequency increase. The concentration of malonic acid, the organic substrate, affects the system but with lower intensity compared with the combination of sodium bromate and temperature. On the other hand, the Cu/Cu2O electrochemical oscillator was shown to be less sensitive to changes in the temperature. The applied current density and pH were the two parameters which most perturbed the system. Interestingly, the frequency behaved nonmonotonically with a quadratic dependence. The multivariate analysis of both oscillators exhibited significant differences - while the homogenous oscillator displayed a linear dependence with the factors, the heterogeneous one revealed a more complex dependence with quadratic terms. Our results may contribute, for instance, in the synthesis of self-organized materials in which an accurate frequency selection is required and, depending on its value, different physicochemical properties are obtained.
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Affiliation(s)
- Bianca T Kitagaki
- Institute of Chemistry, University of Campinas, CEP 13083-970, Campinas, SP, Brazil.
| | - Maria R Pinto
- Institute of Chemistry, University of Campinas, CEP 13083-970, Campinas, SP, Brazil.
| | - Adriana C Queiroz
- Institute of Chemistry, University of Campinas, CEP 13083-970, Campinas, SP, Brazil. and Center for Innovation on New Energies, University of Campinas, CEP 13083-841, Campinas, SP, Brazil
| | - Márcia C Breitkreitz
- Institute of Chemistry, University of Campinas, CEP 13083-970, Campinas, SP, Brazil.
| | - Federico Rossi
- Department of Earth, Environmental and Physical Sciences - DEEP Sciences, University of Siena, Pian dei Mantellini 44, 53100, Siena, Italy
| | - Raphael Nagao
- Institute of Chemistry, University of Campinas, CEP 13083-970, Campinas, SP, Brazil. and Center for Innovation on New Energies, University of Campinas, CEP 13083-841, Campinas, SP, Brazil
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Melle GB, Hartl FW, Varela H, Sitta E. The effect of solution pH on the oscillatory electro-oxidation of methanol. J Electroanal Chem (Lausanne) 2018. [DOI: 10.1016/j.jelechem.2018.08.033] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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10
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Hartl FW, Varela H. The Effect of Solution pH and Temperature on the Oscillatory Electro-Oxidation of Formic Acid on Platinum. ChemistrySelect 2017. [DOI: 10.1002/slct.201702008] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Fabian W. Hartl
- Department of Physical Chemistry; Institute of Chemistry of São Carlos; University of São Paulo, POBox 780; 13560-970 São Carlos, SP Brazil
| | - Hamilton Varela
- Department of Physical Chemistry; Institute of Chemistry of São Carlos; University of São Paulo, POBox 780; 13560-970 São Carlos, SP Brazil
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Hartl FW, Zülke AA, Fonte BJ, Varela H. Temperature dependence of the evolving oscillations along the electrocatalytic oxidation of methanol. J Electroanal Chem (Lausanne) 2017. [DOI: 10.1016/j.jelechem.2016.11.032] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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