| Full text | |
| Author(s): |
Moraes, A.
[1]
;
Assumpcao, M. H. M. T.
[1]
;
Papai, R.
[1]
;
Gaubeur, I.
[1]
;
Rocha, R. S.
[2]
;
Reis, R. M.
[2]
;
Calegaro, M. L.
[2]
;
Lanza, M. R. V.
[2]
;
Santos, M. C.
[1]
Total Authors: 9
|
| Affiliation: | [1] UFABC Univ Fed ABC, CCNH Ctr Ciencias Nat & Humanas, BR-09210170 Santo Andre, SP - Brazil
[2] Univ Sao Paulo, Inst Quim Sao Carlos, BR-13566590 Sao Carlos, SP - Brazil
Total Affiliations: 2
|
| Document type: | Journal article |
| Source: | JOURNAL OF ELECTROANALYTICAL CHEMISTRY; v. 719, p. 127-132, APR 1 2014. |
| Web of Science Citations: | 17 |
| Abstract | |
This paper reports the use of different proportions of vanadium nanostructured electrocatalysts for H2O2 electrogeneration. A comparative study using different mass proportions of vanadium (1%, 6%, 12%, 15% and 20%) was performed to produce H2O2. The V/C materials were prepared by a modified polymeric precursor method (PPM) and characterized by X-ray diffraction and transmission electron microscopy (TEM) analysis. XRD results identified different phases comprising V2O5 and VO2 while TEM micrographs show the vanadium nanoparticles in the range of 1-3 nm. The rotating ring-disk electrode (RRDE) technique was used to evaluate the kinetics of the oxygen reduction reaction (ORR). The results showed that the 12% V/C prepared by the PPM was the best composite among those investigated for the production of H2O2 in a 1 mol L-1 NaOH electrolyte solution because this electrocatalyst exhibited a H2O2 conversion efficiency of 68%. The ring current obtained with 12% V/C was greater than the obtained with Vulcan carbon, which was used as a reference material for H2O2 production and exhibited an efficiency of 31%. After the study with the RRDE, gas-diffusion electrodes (GDEs) containing the catalyst were used to evaluate the amount of H2O2 produced during exhaustive electrolysis. On the basis of these results, the 12% V/C GDE produced 620 mg L-1 of H2O2 in alkaline media, whereas the Vulcan carbon GDE produced only 369 mg L-1 at the same potential. In acidic media, the 12% V/C GDE produced 107 mg L-1 of H2O2, whereas Vulcan carbon produced only 72 mg L-1 at the same potential, indicating the better activity of V/C for H2O2 electrogeneration. The 12% V/C is composed primarily of the V2O5 phase, which shows acidic character that can increase the acidity of the surface, providing greater hydrophilicity and, consequently, greater activity toward the ORR via two-electron transference. (c) 2014 Elsevier B.V. All rights reserved. (AU) | |
| FAPESP's process: | 05/59992-6 - Materiais nanoestruturados: eletrocatalise e membranas de oxidos. |
| Grantee: | Mauro Coelho dos Santos |
| Support Opportunities: | Research Grants - Young Investigators Grants |
| FAPESP's process: | 10/16511-6 - Energy Generation from Biofuel using Nanostructures |
| Grantee: | Mauro Coelho dos Santos |
| Support Opportunities: | Regular Research Grants |
| FAPESP's process: | 07/04759-0 - Gas diffusion electrodes modified by organometallic compounds for hydrogen peroxide production |
| Grantee: | Marcos Roberto de Vasconcelos Lanza |
| Support Opportunities: | Regular Research Grants |
| FAPESP's process: | 09/09145-6 - Study of Ethanol Electrochemical Oxidation Mechanism on PtSn, PtCe and PtSnCe using In-situ Spectroscopic Techniques |
| Grantee: | Rodrigo Fernando Brambilla de Souza |
| Support Opportunities: | Scholarships in Brazil - Doctorate |
| FAPESP's process: | 10/04539-3 - Synthesis and Characterization of Nanostructured electrocatalysts for hydrogen peroxide in-situ Obtaining and subsequent degradation of organic pollutants |
| Grantee: | Mônica Helena Marcon Teixeira Assumpção |
| Support Opportunities: | Scholarships in Brazil - Doctorate (Direct) |
| FAPESP's process: | 10/10546-2 - Study and Development of nanostructured materials based on Ce and V for in situ hydrogen peroxide production |
| Grantee: | André Moraes |
| Support Opportunities: | Scholarships in Brazil - Scientific Initiation |