Photoelectrochemical reduction of CO2 on Cu/Cu2O films: Product distribution and pH effects
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Data
2015-03-15
Autores
Brito, Juliana Ferreira de [UNESP]
Araujo, Angela Regina [UNESP]
Rajeshwar, Krishnan
Zanoni, Maria Valnice Boldrin [UNESP]
Título da Revista
ISSN da Revista
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Editor
Elsevier B.V.
Resumo
This work focuses on photoelectrochemical CO2 reduction at a Cu/Cu2O electrode (1 x 1 cm(2)). The formation of methanol, ethanol, formaldehyde, acetaldehyde, and acetone was monitored during UV-visible radiation for 3 h at +0.20 V (vs. Ag/AgCl reference); 80% of the initial CO2 was removed. In this process, the photogenerated electrons in the p-type Cu2O semiconductor reduced CO2 (CO2 + e(-) --> CO2-center dot). Subsequent reaction involved radical species that originated during photolysis and dictated the product distribution observed. Methanol formation prevailed for a short period (<30 min); acetaldehyde and acetone were the main products after a longer accumulation period (>120 min). A reaction scheme is presented to account for the product evolution and reactions with the H-center dot, CH3 center dot, and OH center dot radical species generated in situ. The medium pH was identified as a key variable in the selectivity of the methanol formation. (C) 2014 Elsevier B.V. All rights reserved.
Descrição
Palavras-chave
Cu/Cu2O semiconductor, Carbon dioxide conversion, Synthesis of methanol from CO2
Como citar
Chemical Engineering Journal, v. 264, p. 302-309, 2015.