Nanocompósitos MWCNT/Nb₂O₅ e MWCNT/TiO₂: Síntese, Caracterização e Aplicação em Sensores Eletroquímicos

Detalhes bibliográficos
Autor(a) principal: RAFAEL HENRIQUE DE OLIVEIRA
Data de Publicação: 2023
Tipo de documento: Tese
Idioma: por
Título da fonte: Repositório Institucional da UFMS
Texto Completo: https://repositorio.ufms.br/handle/123456789/6527
Resumo: Electrochemical sensors play a crucial role in the accurate detection of chemical compounds in various areas, including clinical analysis and environmental monitoring. In this context, nanocomposites of carbonaceous materials and metal oxides have emerged as highly promising materials. This work aims to synthesize and characterize nanocomposites for application in electrochemical sensors. A new nanocomposite was obtained by decorating multi-walled carbon nanotubes (MWCNTs) with Nb₂O₅ using the peroxide oxidative complex method (OPM) combined with hydrothermal treatment. Additionally, the nanocomposite with MWCNTs and TiO₂ was obtained by the solvothermal method. The materials were characterized using techniques such as scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), and thermogravimetric analysis (TGA). The nanocomposites were used as modifiers of glassy carbon electrodes (GCE) in the fabrication of GCE/MWCNT/Nb₂O₅ and GCE/MWCNT/TiO₂ sensors. The electrochemical response of these sensors was evaluated through cyclic voltammetry (CV) in solutions such as H₂SO₄ (pH 2.0) and Britton-Robinson buffer solution (pH 7.0). The sensors demonstrated promising sensitivity and selectivity in the detection of H₂O₂ and paracetamol in an aqueous medium. By means of cyclic voltammetry, the GCE/MWCNT/Nb₂O₅ sensor exhibited a detection limit (LD) of 1.5 μM and a quantification limit (LQ) of 5.0 μM for H₂O₂. The GCE/MWCNT/TiO₂ sensor revealed an LD of 4.0 μM and an LQ of 14.0 μM. The electrocatalytic activity of the GCE/MWCNT/Nb₂O₅ sensor in paracetamol detection, even in the presence of interferents such as epinephrine and tryptophan, was also remarkable. Square wave voltammetry achieved an LD of 0.11 nM and an LQ of 0.49 nM, surpassing previous studies. These results indicate the potential of these nanocomposites as materials for the development of more efficient electrochemical sensors, with promising application in clinical and environmental samples.
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spelling 2023-09-05T18:48:55Z2023-09-05T18:48:55Z2023https://repositorio.ufms.br/handle/123456789/6527Electrochemical sensors play a crucial role in the accurate detection of chemical compounds in various areas, including clinical analysis and environmental monitoring. In this context, nanocomposites of carbonaceous materials and metal oxides have emerged as highly promising materials. This work aims to synthesize and characterize nanocomposites for application in electrochemical sensors. A new nanocomposite was obtained by decorating multi-walled carbon nanotubes (MWCNTs) with Nb₂O₅ using the peroxide oxidative complex method (OPM) combined with hydrothermal treatment. Additionally, the nanocomposite with MWCNTs and TiO₂ was obtained by the solvothermal method. The materials were characterized using techniques such as scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), and thermogravimetric analysis (TGA). The nanocomposites were used as modifiers of glassy carbon electrodes (GCE) in the fabrication of GCE/MWCNT/Nb₂O₅ and GCE/MWCNT/TiO₂ sensors. The electrochemical response of these sensors was evaluated through cyclic voltammetry (CV) in solutions such as H₂SO₄ (pH 2.0) and Britton-Robinson buffer solution (pH 7.0). The sensors demonstrated promising sensitivity and selectivity in the detection of H₂O₂ and paracetamol in an aqueous medium. By means of cyclic voltammetry, the GCE/MWCNT/Nb₂O₅ sensor exhibited a detection limit (LD) of 1.5 μM and a quantification limit (LQ) of 5.0 μM for H₂O₂. The GCE/MWCNT/TiO₂ sensor revealed an LD of 4.0 μM and an LQ of 14.0 μM. The electrocatalytic activity of the GCE/MWCNT/Nb₂O₅ sensor in paracetamol detection, even in the presence of interferents such as epinephrine and tryptophan, was also remarkable. Square wave voltammetry achieved an LD of 0.11 nM and an LQ of 0.49 nM, surpassing previous studies. These results indicate the potential of these nanocomposites as materials for the development of more efficient electrochemical sensors, with promising application in clinical and environmental samples.Sensores eletroquímicos desempenham um papel crucial na detecção precisa de compostos químicos em diversas áreas, incluindo análises clínicas, industriais e monitoramento ambiental. Os nanocompósitos de materiais carbonáceos e óxidos metálicos têm se destacado como materiais altamente promissores nesse contexto. Este trabalho teve como objetivo a síntese e caracterização de nanocompósitos para aplicação em sensores eletroquímicos. Um novo nanocompósito foi obtido utilizando nanotubos de carbono multicamadas (MWCNTs) decorados com Nb₂O₅, por meio do método dos complexos oxidantes de peróxido (OPM) associado ao tratamento hidrotérmico. Além disso, outro nanocompósito composto por MWCNTs e TiO₂ foi obtido pelo método solvotérmico. Os materiais foram caracterizados utilizando técnicas como microscopia eletrônica de varredura (MEV), espectroscopia de raios-X por energia dispersiva (EDS), difração de raios-X (XRD) e análise termogravimétrica (TGA). Os nanocompósitos foram utilizados como modificadores de eletrodos de carbono vítreo (GCE) na fabricação dos sensores GCE/MWCNT/Nb₂O₅ e GCE/MWCNT/TiO₂. A resposta eletroquímica desses sensores foi avaliada por meio de voltametria cíclica (CV) em soluções como H₂SO₄ (pH 2,0) e solução tampão Britton-Robson (pH 7,0). Os sensores demonstraram sensibilidade e seletividade promissoras nas detecções de H₂O₂ e paracetamol em meio aquoso. Através da voltametria cíclica, o sensor GCE/MWCNT/Nb₂O₅ apresentou limite de detecção (LD) de 1,5 μM e limite de quantificação (LQ) de 5,0 μM para o H₂O₂. O sensor GCE/MWCNT/TiO₂ revelou um LD de 4,0 μM e um LQ de 14,0 μM. Destaca-se também a notável atividade eletrocatalítica do sensor GCE/MWCNT/Nb₂O₅ na detecção de paracetamol, mesmo na presença de interferentes como epinefrina e triptofano. Por meio da voltametria de onda quadrada, alcançou-se um LD de 0,11 nM e um LQ de 0,49 nM, superando estudos anteriores. Esses resultados indicam o potencial desses nanocompósitos como materiais para o desenvolvimento de sensores eletroquímicos mais eficientes, com aplicação potencial em amostras clínicas e ambientais.Fundação Universidade Federal de Mato Grosso do SulUFMSBrasilNanocompósitosSensores eletroquímicosH2O2Paracetamol.Nanocompósitos MWCNT/Nb₂O₅ e MWCNT/TiO₂: Síntese, Caracterização e Aplicação em Sensores Eletroquímicosinfo:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/doctoralThesisDiogo Duarte dos ReisRAFAEL HENRIQUE DE OLIVEIRAinfo:eu-repo/semantics/openAccessporreponame:Repositório Institucional da UFMSinstname:Universidade Federal de Mato Grosso do Sul (UFMS)instacron:UFMSORIGINALTese Versão Final - RAFAEL HENRIQUE DE OLIVEIRA- PPGCM.pdfTese Versão Final - RAFAEL HENRIQUE DE OLIVEIRA- PPGCM.pdfapplication/pdf2725013https://repositorio.ufms.br/bitstream/123456789/6527/-1/Tese%20Vers%c3%a3o%20Final%20-%20RAFAEL%20HENRIQUE%20DE%20OLIVEIRA-%20PPGCM.pdf56481bb527639595ad74052729bf8ee3MD5-1123456789/65272023-09-05 14:48:57.068oai:repositorio.ufms.br:123456789/6527Repositório InstitucionalPUBhttps://repositorio.ufms.br/oai/requestri.prograd@ufms.bropendoar:21242023-09-05T18:48:57Repositório Institucional da UFMS - Universidade Federal de Mato Grosso do Sul (UFMS)false
dc.title.pt_BR.fl_str_mv Nanocompósitos MWCNT/Nb₂O₅ e MWCNT/TiO₂: Síntese, Caracterização e Aplicação em Sensores Eletroquímicos
title Nanocompósitos MWCNT/Nb₂O₅ e MWCNT/TiO₂: Síntese, Caracterização e Aplicação em Sensores Eletroquímicos
spellingShingle Nanocompósitos MWCNT/Nb₂O₅ e MWCNT/TiO₂: Síntese, Caracterização e Aplicação em Sensores Eletroquímicos
RAFAEL HENRIQUE DE OLIVEIRA
Nanocompósitos
Sensores eletroquímicos
H2O2
Paracetamol.
title_short Nanocompósitos MWCNT/Nb₂O₅ e MWCNT/TiO₂: Síntese, Caracterização e Aplicação em Sensores Eletroquímicos
title_full Nanocompósitos MWCNT/Nb₂O₅ e MWCNT/TiO₂: Síntese, Caracterização e Aplicação em Sensores Eletroquímicos
title_fullStr Nanocompósitos MWCNT/Nb₂O₅ e MWCNT/TiO₂: Síntese, Caracterização e Aplicação em Sensores Eletroquímicos
title_full_unstemmed Nanocompósitos MWCNT/Nb₂O₅ e MWCNT/TiO₂: Síntese, Caracterização e Aplicação em Sensores Eletroquímicos
title_sort Nanocompósitos MWCNT/Nb₂O₅ e MWCNT/TiO₂: Síntese, Caracterização e Aplicação em Sensores Eletroquímicos
author RAFAEL HENRIQUE DE OLIVEIRA
author_facet RAFAEL HENRIQUE DE OLIVEIRA
author_role author
dc.contributor.advisor1.fl_str_mv Diogo Duarte dos Reis
dc.contributor.author.fl_str_mv RAFAEL HENRIQUE DE OLIVEIRA
contributor_str_mv Diogo Duarte dos Reis
dc.subject.por.fl_str_mv Nanocompósitos
Sensores eletroquímicos
H2O2
Paracetamol.
topic Nanocompósitos
Sensores eletroquímicos
H2O2
Paracetamol.
description Electrochemical sensors play a crucial role in the accurate detection of chemical compounds in various areas, including clinical analysis and environmental monitoring. In this context, nanocomposites of carbonaceous materials and metal oxides have emerged as highly promising materials. This work aims to synthesize and characterize nanocomposites for application in electrochemical sensors. A new nanocomposite was obtained by decorating multi-walled carbon nanotubes (MWCNTs) with Nb₂O₅ using the peroxide oxidative complex method (OPM) combined with hydrothermal treatment. Additionally, the nanocomposite with MWCNTs and TiO₂ was obtained by the solvothermal method. The materials were characterized using techniques such as scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), and thermogravimetric analysis (TGA). The nanocomposites were used as modifiers of glassy carbon electrodes (GCE) in the fabrication of GCE/MWCNT/Nb₂O₅ and GCE/MWCNT/TiO₂ sensors. The electrochemical response of these sensors was evaluated through cyclic voltammetry (CV) in solutions such as H₂SO₄ (pH 2.0) and Britton-Robinson buffer solution (pH 7.0). The sensors demonstrated promising sensitivity and selectivity in the detection of H₂O₂ and paracetamol in an aqueous medium. By means of cyclic voltammetry, the GCE/MWCNT/Nb₂O₅ sensor exhibited a detection limit (LD) of 1.5 μM and a quantification limit (LQ) of 5.0 μM for H₂O₂. The GCE/MWCNT/TiO₂ sensor revealed an LD of 4.0 μM and an LQ of 14.0 μM. The electrocatalytic activity of the GCE/MWCNT/Nb₂O₅ sensor in paracetamol detection, even in the presence of interferents such as epinephrine and tryptophan, was also remarkable. Square wave voltammetry achieved an LD of 0.11 nM and an LQ of 0.49 nM, surpassing previous studies. These results indicate the potential of these nanocomposites as materials for the development of more efficient electrochemical sensors, with promising application in clinical and environmental samples.
publishDate 2023
dc.date.accessioned.fl_str_mv 2023-09-05T18:48:55Z
dc.date.available.fl_str_mv 2023-09-05T18:48:55Z
dc.date.issued.fl_str_mv 2023
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dc.publisher.none.fl_str_mv Fundação Universidade Federal de Mato Grosso do Sul
dc.publisher.initials.fl_str_mv UFMS
dc.publisher.country.fl_str_mv Brasil
publisher.none.fl_str_mv Fundação Universidade Federal de Mato Grosso do Sul
dc.source.none.fl_str_mv reponame:Repositório Institucional da UFMS
instname:Universidade Federal de Mato Grosso do Sul (UFMS)
instacron:UFMS
instname_str Universidade Federal de Mato Grosso do Sul (UFMS)
instacron_str UFMS
institution UFMS
reponame_str Repositório Institucional da UFMS
collection Repositório Institucional da UFMS
bitstream.url.fl_str_mv https://repositorio.ufms.br/bitstream/123456789/6527/-1/Tese%20Vers%c3%a3o%20Final%20-%20RAFAEL%20HENRIQUE%20DE%20OLIVEIRA-%20PPGCM.pdf
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