Detalhes bibliográficos
| Resumo: | Nickel-copper metallic foams were electrodeposited from an acidic electrolyte, using hydrogen bubble evolution as a dynamic template. Their morphology and chemical composition was studied by scanning electron microscopy and related to the deposition parameters (applied current density and deposition time). For high currents densities (above 1 A cm(-2)) the nickel-copper deposits have a three-dimensional foam-like morphology with randomly distributed nearly-circular pores whose walls present an open dendritic structure. The nickel-copper foams are crystalline and composed of pure nickel and a copper-rich phase containing nickel in solid solution. The electrochemical behaviour of the material was studied by cyclic voltammetry and chronopotentiometry (charge-discharge curves) aiming at its application as a positive electrode for supercapacitors. Cyclic voltammograms showed that the Ni-Cu foams have a pseudocapacitive behaviour. The specific capacitance was calculated from charge-discharge data and the best value (105 F g(-1) at 1 mA cm(-2)) was obtained for nickel-copper foams deposited at 1.8 A cm(-2) for 180 s. Cycling stability of these foams was also assessed and they present a 90 % capacitance retention after 10,000 cycles at 10 mA cm(-2). |
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| Autores principais: | Eugénio, S. |
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| Outros Autores: | Silva, Maria Teresa Oliveira de Moura e; Carmezim, M. J.; Duarte, R. G.; Montemor, M. F. |
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| Assunto: | Nickel-copper Nanostructured foams Electrodeposition Electrodes for supercapacitors |
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| Ano: | 2014 |
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| País: | Portugal |
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| Tipo de documento: | artigo |
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| Tipo de acesso: | acesso restrito |
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| Instituição associada: | Universidade Politécnica de Lisboa |
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| Idioma: | inglês |
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| Origem: | Repositório Científico da Universidade Politécnica de Lisboa |
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