Banca de DEFESA: LUIZ CARLOS DOMINGOS BATISTA
Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.DISCENTE : LUIZ CARLOS DOMINGOS BATISTA
DATA : 10/12/2018
HORA: 09:00
LOCAL: Auditório do CCET
TÍTULO:
CONSTRUCTION OF ELECTRODES MODIFIED WITH MOF FOR DETERMINATION OF POLLUTANTS IN AQUEOUS MEDIUM
PALAVRAS-CHAVES:
“Metal-Organic Framework (MOF)”, “Electrochemical sensors”, “Carbon Paste Electrode”, “Environmental applications”.
PÁGINAS: 100
GRANDE ÁREA: Ciências Exatas e da Terra
ÁREA: Química
SUBÁREA: Química Analítica
ESPECIALIDADE: Análise de Traços e Química Ambiental
RESUMO:
MOFs are a new category of porous crystalline compounds consisting of metal ions or clusters and organic binders connected by coordinate bonds, having important characteristics such as flexibility, high porosity, high surface area and a variety of pore size . Besides these characteristics the MOFs also have excellent electrocatalytic properties and can be used as modifiers of electrochemical electrodes used as sensors whose presence significantly improves the sensitivity of their precursors. In this work two electrodes of carbon paste modified with MOF 235 and MOF Cu-(1,4 – BDC) were developed. The MOFs were synthesized by soldering using Fe2 + and Cu2 + ions and 1,4-benzenedicarboxylic acid (1,4-BDC) as a binder. The samples were characterized by X-ray Diffraction (XRD) and Fourier transform Mean Intra-red (FTIR). Both MOFs were mixed to analytical grade granfite (in a ratio of 10% MOF) and paraffinic oil forming a homogeneous mixture, inserted into a glass tube with Copper rod forming the modified carbon paste electrode with MOF which were characterized electrochemically by cyclic voltammetry where information with reversibility and electroactive surface area of the electrodes were removed, which were reversible and with a larger surface area than the unmodified carbon paste. The electrode modified with MOF -235 was applied for the detection of lead ions in aqueous solution, obtaining a detection limit of 18 μg.L-1 with a correlation coefficient of (R²) of 0.9962 in a range of 50 to 300 μg.L- 1. The same electrode was used for the detection of polyphenols that had Catechol as an example of application. The electrode obtained a detection limit of 50 μmol.L-1 with a correlation coefficient of (R²) of 0.9902 in a working range of 90 to 514 μmol.L-1. The MOF Cu –(1,4- BDC) was also applied for the detection of polyphenols, using catechol as an example and obtained the limit detection result of 32 μmol.L - 1 with a correlation coefficient of (R²) of 0.9972 in a working range of 90 to 750 μmol.L-1. thus showing that the modified electrodes present high sensitivity and high linearity for the compounds studied.
MEMBROS DA BANCA:
Presidente - 1645110 - CARLOS ALBERTO MARTINEZ HUITLE
Interno - 348475 - DJALMA RIBEIRO DA SILVA
Externo à Instituição - MARCO ANTONIO QUIROZ ALFARO - udlap
Externo ao Programa - 1412709 - NEDJA SUELY FERNANDES
Externo à Instituição - SUELY SOUZA LEAL DE CASTRO - UERN