Comparison of the Electrochemical Response of Carbon-Fiber-Reinforced Plastic (CFRP), Glassy Carbon, and Highly Ordered Pyrolytic Graphite (HOPG) in Near-Neutral Aqueous Chloride Media
Carbon-fiber-reinforced polymers (CFRP), being conductive, are capable of supporting cathodic oxygen reduction reactions (ORR) and thus promote galvanic corrosion when coupled to many metallic materials. Hence, understanding cathodic processes at carbon surfaces is critical to developing new strateg...
| Main Authors: | , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2023-01-01
|
| Series: | C |
| Subjects: | |
| Online Access: | https://www.mdpi.com/2311-5629/9/1/7 |
| _version_ | 1797612919030022144 |
|---|---|
| author | Stanley Udochukwu Ofoegbu Mário Guerreiro Silva Ferreira Helena I. S. Nogueira Mikhail Zheludkevich |
| author_facet | Stanley Udochukwu Ofoegbu Mário Guerreiro Silva Ferreira Helena I. S. Nogueira Mikhail Zheludkevich |
| author_sort | Stanley Udochukwu Ofoegbu |
| collection | DOAJ |
| description | Carbon-fiber-reinforced polymers (CFRP), being conductive, are capable of supporting cathodic oxygen reduction reactions (ORR) and thus promote galvanic corrosion when coupled to many metallic materials. Hence, understanding cathodic processes at carbon surfaces is critical to developing new strategies for the corrosion protection of multi-material assemblies. In the present work, the electrochemical responses of CFRP, glassy carbon, and HOPG (Highly Ordered Pyrolytic Graphite) have been evaluated in a quiescent 50 mM NaCl solution, and their respective activities towards ORR have been ranked. Employing the averages of the specific charges (CFRP, 129.52 mC cm<sup>−2</sup>; glassy carbon, 89.95 mC cm<sup>−2</sup>; HOPG, 60.77 mC cm<sup>−2</sup>) passed during 1 h polarization of each of the 3 carbon surfaces at −1000 mV<sub>SCE</sub> in the test media as a ranking criterion, the propensities of the 3 carbon surfaces (CFRP, GC, and HOPG) to support cathodic activities that can lead to anodic metal dissolution on galvanic coupling to metallic materials are ranked thusly; CFRP > GC > HOPG. This ranking is consistent with the trend of capacitance values obtained in this work: CFRP (19.5 to 34.5 μF cm<sup>−2</sup>), glassy carbon (13.6 to 85.5 μF cm<sup>−2</sup>), and HOPG (1.4 to 1.8 μF cm<sup>−2</sup>). A comparison of electrochemical data at potentials relevant to galvanic coupling to metals indicated that at these cathodic potential(s) the CFRP surface is the most electrochemically active of the studied carbon surfaces. On the basis of the values and trends of the electrochemical parameters evaluated, it is postulated that the observed differences in the electrochemical responses of these 3 carbon-rich surfaces to ORR are significantly due to differences in the proportions of edge sites present on each carbon surface. These results could provide valuable insights on plausible strategies for designing carbon surfaces and carbon fiber composites with reduced activity toward ORR for corrosion protection applications or enhanced activity towards ORR for energy applications. |
| first_indexed | 2024-03-11T06:48:39Z |
| format | Article |
| id | doaj.art-6b5fa750ff3f4358ac7f07514ac62aab |
| institution | Directory Open Access Journal |
| issn | 2311-5629 |
| language | English |
| last_indexed | 2024-03-11T06:48:39Z |
| publishDate | 2023-01-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | C |
| spelling | doaj.art-6b5fa750ff3f4358ac7f07514ac62aab2023-11-17T10:09:08ZengMDPI AGC2311-56292023-01-0191710.3390/c9010007Comparison of the Electrochemical Response of Carbon-Fiber-Reinforced Plastic (CFRP), Glassy Carbon, and Highly Ordered Pyrolytic Graphite (HOPG) in Near-Neutral Aqueous Chloride MediaStanley Udochukwu Ofoegbu0Mário Guerreiro Silva Ferreira1Helena I. S. Nogueira2Mikhail Zheludkevich3Centre for Mechanical Technology and Automation (TEMA), Department of Mechanical Engineering, University of Aveiro, Campus Universitário de Santiago, 3810-193 Aveiro, PortugalDepartment of Materials and Ceramic Engineering, CICECO-Aveiro Institute of Materials, University of Aveiro, Campus Universitário de Santiago, 3810-193 Aveiro, PortugalDepartment of Chemistry, CICECO-Aveiro Institute of Materials, University of Aveiro, Campus Universitário de Santiago, 3810-193 Aveiro, PortugalInstitute of Surface Science, Helmholtz-Zentrum Hereon, Max-Planck-Strasse 1, 21502 Geesthacht, GermanyCarbon-fiber-reinforced polymers (CFRP), being conductive, are capable of supporting cathodic oxygen reduction reactions (ORR) and thus promote galvanic corrosion when coupled to many metallic materials. Hence, understanding cathodic processes at carbon surfaces is critical to developing new strategies for the corrosion protection of multi-material assemblies. In the present work, the electrochemical responses of CFRP, glassy carbon, and HOPG (Highly Ordered Pyrolytic Graphite) have been evaluated in a quiescent 50 mM NaCl solution, and their respective activities towards ORR have been ranked. Employing the averages of the specific charges (CFRP, 129.52 mC cm<sup>−2</sup>; glassy carbon, 89.95 mC cm<sup>−2</sup>; HOPG, 60.77 mC cm<sup>−2</sup>) passed during 1 h polarization of each of the 3 carbon surfaces at −1000 mV<sub>SCE</sub> in the test media as a ranking criterion, the propensities of the 3 carbon surfaces (CFRP, GC, and HOPG) to support cathodic activities that can lead to anodic metal dissolution on galvanic coupling to metallic materials are ranked thusly; CFRP > GC > HOPG. This ranking is consistent with the trend of capacitance values obtained in this work: CFRP (19.5 to 34.5 μF cm<sup>−2</sup>), glassy carbon (13.6 to 85.5 μF cm<sup>−2</sup>), and HOPG (1.4 to 1.8 μF cm<sup>−2</sup>). A comparison of electrochemical data at potentials relevant to galvanic coupling to metals indicated that at these cathodic potential(s) the CFRP surface is the most electrochemically active of the studied carbon surfaces. On the basis of the values and trends of the electrochemical parameters evaluated, it is postulated that the observed differences in the electrochemical responses of these 3 carbon-rich surfaces to ORR are significantly due to differences in the proportions of edge sites present on each carbon surface. These results could provide valuable insights on plausible strategies for designing carbon surfaces and carbon fiber composites with reduced activity toward ORR for corrosion protection applications or enhanced activity towards ORR for energy applications.https://www.mdpi.com/2311-5629/9/1/7galvanic couplingCFRPcarbon surfacescathodic polarizationoxygen reduction reactions (ORR)multi-material combinations |
| spellingShingle | Stanley Udochukwu Ofoegbu Mário Guerreiro Silva Ferreira Helena I. S. Nogueira Mikhail Zheludkevich Comparison of the Electrochemical Response of Carbon-Fiber-Reinforced Plastic (CFRP), Glassy Carbon, and Highly Ordered Pyrolytic Graphite (HOPG) in Near-Neutral Aqueous Chloride Media C galvanic coupling CFRP carbon surfaces cathodic polarization oxygen reduction reactions (ORR) multi-material combinations |
| title | Comparison of the Electrochemical Response of Carbon-Fiber-Reinforced Plastic (CFRP), Glassy Carbon, and Highly Ordered Pyrolytic Graphite (HOPG) in Near-Neutral Aqueous Chloride Media |
| title_full | Comparison of the Electrochemical Response of Carbon-Fiber-Reinforced Plastic (CFRP), Glassy Carbon, and Highly Ordered Pyrolytic Graphite (HOPG) in Near-Neutral Aqueous Chloride Media |
| title_fullStr | Comparison of the Electrochemical Response of Carbon-Fiber-Reinforced Plastic (CFRP), Glassy Carbon, and Highly Ordered Pyrolytic Graphite (HOPG) in Near-Neutral Aqueous Chloride Media |
| title_full_unstemmed | Comparison of the Electrochemical Response of Carbon-Fiber-Reinforced Plastic (CFRP), Glassy Carbon, and Highly Ordered Pyrolytic Graphite (HOPG) in Near-Neutral Aqueous Chloride Media |
| title_short | Comparison of the Electrochemical Response of Carbon-Fiber-Reinforced Plastic (CFRP), Glassy Carbon, and Highly Ordered Pyrolytic Graphite (HOPG) in Near-Neutral Aqueous Chloride Media |
| title_sort | comparison of the electrochemical response of carbon fiber reinforced plastic cfrp glassy carbon and highly ordered pyrolytic graphite hopg in near neutral aqueous chloride media |
| topic | galvanic coupling CFRP carbon surfaces cathodic polarization oxygen reduction reactions (ORR) multi-material combinations |
| url | https://www.mdpi.com/2311-5629/9/1/7 |
| work_keys_str_mv | AT stanleyudochukwuofoegbu comparisonoftheelectrochemicalresponseofcarbonfiberreinforcedplasticcfrpglassycarbonandhighlyorderedpyrolyticgraphitehopginnearneutralaqueouschloridemedia AT marioguerreirosilvaferreira comparisonoftheelectrochemicalresponseofcarbonfiberreinforcedplasticcfrpglassycarbonandhighlyorderedpyrolyticgraphitehopginnearneutralaqueouschloridemedia AT helenaisnogueira comparisonoftheelectrochemicalresponseofcarbonfiberreinforcedplasticcfrpglassycarbonandhighlyorderedpyrolyticgraphitehopginnearneutralaqueouschloridemedia AT mikhailzheludkevich comparisonoftheelectrochemicalresponseofcarbonfiberreinforcedplasticcfrpglassycarbonandhighlyorderedpyrolyticgraphitehopginnearneutralaqueouschloridemedia |