Comparative voltammetric and FTIRRAS study on the electro-oxidation of thiourea and methyl-thioureas on platinum in aqueous acid solutions

A comparative voltammetric and spectroscopic study on thiourea, methylthiourea, 1,3 dimethylthiourea and tetramethylthiourea electro-oxidation is presented. The investigation was performed at platinum electrodes in aqueous acid solutions in the potential range between 0.05 and 1.6 V (versus SHE). Th...

Descripción completa

Detalles Bibliográficos
Autores principales: Bolzán, Agustín Eduardo, Schilardi, Patricia Laura, Piatti, Roberto C. V., Iwasita, T., Cuesta, A., Gutiérrez, C., Arvia, Alejandro Jorge
Formato: Articulo
Lenguaje:Inglés
Publicado: 2004
Materias:
Acceso en línea:http://sedici.unlp.edu.ar/handle/10915/119220
Aporte de:
id I19-R120-10915-119220
record_format dspace
institution Universidad Nacional de La Plata
institution_str I-19
repository_str R-120
collection SEDICI (UNLP)
language Inglés
topic Ciencias Exactas
Química
Thiourea
Methylthiourea
Dimethylthiourea
Tetramethylthiourea
Electro-oxidation
Platinum
FTIRRAS
spellingShingle Ciencias Exactas
Química
Thiourea
Methylthiourea
Dimethylthiourea
Tetramethylthiourea
Electro-oxidation
Platinum
FTIRRAS
Bolzán, Agustín Eduardo
Schilardi, Patricia Laura
Piatti, Roberto C. V.
Iwasita, T.
Cuesta, A.
Gutiérrez, C.
Arvia, Alejandro Jorge
Comparative voltammetric and FTIRRAS study on the electro-oxidation of thiourea and methyl-thioureas on platinum in aqueous acid solutions
topic_facet Ciencias Exactas
Química
Thiourea
Methylthiourea
Dimethylthiourea
Tetramethylthiourea
Electro-oxidation
Platinum
FTIRRAS
description A comparative voltammetric and spectroscopic study on thiourea, methylthiourea, 1,3 dimethylthiourea and tetramethylthiourea electro-oxidation is presented. The investigation was performed at platinum electrodes in aqueous acid solutions in the potential range between 0.05 and 1.6 V (versus SHE). The electro-oxidation of thioureas starts at ca. 0.55 V and it involves at least two reaction stages irrespective of their nature. The first electro-oxidation stage occurs in the range 0.55–0.9 V and involves the formation of a soluble disulphide derivative influenced by the blockage of the electrode surface. The second electro-oxidation stage occurs in the range 0.9–1.6 V and it involves a complex electrochemical process yielding products such as carbon dioxide, sulphate ions, CN- and CO-containing species. The second electro-oxidation stage is likely mediated by the oxygen-containing layer that is produced electrochemically on platinum in that range of potential. The gradual depletion of thioureas and the progressive formation of soluble products in the thin solution layer in contact with the electrode are followed through changes in the band intensities of IR spectra. From the correlation between voltammetric and spectroscopic data a description of global reactions involving the electro-oxidation of thioureas to soluble products in both potential ranges is presented. The proposed reaction pathways are consistent with the participation of different adsorbates as was reported earlier for thioureas on platinum.
format Articulo
Articulo
author Bolzán, Agustín Eduardo
Schilardi, Patricia Laura
Piatti, Roberto C. V.
Iwasita, T.
Cuesta, A.
Gutiérrez, C.
Arvia, Alejandro Jorge
author_facet Bolzán, Agustín Eduardo
Schilardi, Patricia Laura
Piatti, Roberto C. V.
Iwasita, T.
Cuesta, A.
Gutiérrez, C.
Arvia, Alejandro Jorge
author_sort Bolzán, Agustín Eduardo
title Comparative voltammetric and FTIRRAS study on the electro-oxidation of thiourea and methyl-thioureas on platinum in aqueous acid solutions
title_short Comparative voltammetric and FTIRRAS study on the electro-oxidation of thiourea and methyl-thioureas on platinum in aqueous acid solutions
title_full Comparative voltammetric and FTIRRAS study on the electro-oxidation of thiourea and methyl-thioureas on platinum in aqueous acid solutions
title_fullStr Comparative voltammetric and FTIRRAS study on the electro-oxidation of thiourea and methyl-thioureas on platinum in aqueous acid solutions
title_full_unstemmed Comparative voltammetric and FTIRRAS study on the electro-oxidation of thiourea and methyl-thioureas on platinum in aqueous acid solutions
title_sort comparative voltammetric and ftirras study on the electro-oxidation of thiourea and methyl-thioureas on platinum in aqueous acid solutions
publishDate 2004
url http://sedici.unlp.edu.ar/handle/10915/119220
work_keys_str_mv AT bolzanagustineduardo comparativevoltammetricandftirrasstudyontheelectrooxidationofthioureaandmethylthioureasonplatinuminaqueousacidsolutions
AT schilardipatricialaura comparativevoltammetricandftirrasstudyontheelectrooxidationofthioureaandmethylthioureasonplatinuminaqueousacidsolutions
AT piattirobertocv comparativevoltammetricandftirrasstudyontheelectrooxidationofthioureaandmethylthioureasonplatinuminaqueousacidsolutions
AT iwasitat comparativevoltammetricandftirrasstudyontheelectrooxidationofthioureaandmethylthioureasonplatinuminaqueousacidsolutions
AT cuestaa comparativevoltammetricandftirrasstudyontheelectrooxidationofthioureaandmethylthioureasonplatinuminaqueousacidsolutions
AT gutierrezc comparativevoltammetricandftirrasstudyontheelectrooxidationofthioureaandmethylthioureasonplatinuminaqueousacidsolutions
AT arviaalejandrojorge comparativevoltammetricandftirrasstudyontheelectrooxidationofthioureaandmethylthioureasonplatinuminaqueousacidsolutions
bdutipo_str Repositorios
_version_ 1764820448018694146