Banca de DEFESA: JOAO FERREIRA DA CRUZ FILHO

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
DISCENTE: JOAO FERREIRA DA CRUZ FILHO
DATA: 25/07/2024
HORA: 08:30
LOCAL: Auditório do Geratec-UESPI
TÍTULO: Sintese, caracterização e atividade fotocatalítica da heterojunção Ag3PO4/UNMOFs na degradação do antibiótico levofloxacina sob irradiação de WLEDs
PALAVRAS-CHAVES: Advanced oxidation process, emerging pollutant, wastewater treatment, heterogeneous photocatalysis, PET recycling
PÁGINAS: 100
GRANDE ÁREA: Ciências Exatas e da Terra
ÁREA: Química
SUBÁREA: Físico-Química
ESPECIALIDADE: Cinética Química e Catálise
RESUMO:

This work presents the synthesis, characterization and photocatalytic activity of the Ag3PO4/UMOFNs(x) heterojunction (where x =5, 10 and 20 wt%) in the degradation of the antibiotic levofloxacin (LVX) under white light-emitting diodes (WLEDs). MOFs, UMOFNs (ultrafine metal-organic structure nanosheets) bimetallic Co-Ni and Ag3PO4 were synthesized via hydrothermal, sonication-exfoliation and precipitation methods, respectively. The X-ray diffraction (XRD) standards, as well as the structural refinement methods, showed that MOFs and Ag3PO4 have triclinic crystalline phases with P 1 (2) space group and cubic centered body with space group P43n (218) space group, respectively. The results of micro-Raman and FT-IR, X-ray photoelectron spectroscopy (XPS), thermogravimetric analyses (TGA), SEM/EDS, and Zeta potential (ζº) indicated the chemical composition, hydration degree, and that samples have spherical, tabular and lamellar morphology respectively for the Ag3PO4, MOF and UMOFNs, with a specific surface charge in the range of 19.8mV to 45.1mV. UV-vis diffuse reflectance spectroscopy (DRS) revealed that the band-gap energy of the UMOFNs was ≈3.14eV, while the
Ag3PO4 sample showed a band-gap energy (Eg) ≈of 2.50eV, with no significant variation of the Eg values for the synthesized heterojunctions. The Ag3PO4 and Ag3PO4/UMOFNs(x) heterojunctions (x =5, 10 and 20wt%) showed LVX degradation efficiency under WLEDs irradiation of 92.5, 81.0, 75.0% and 70.0%, respectively, under power density 11.0mW.cm2 at 60min. In the third photocatalytic cycle, the catalytic efficiency of Ag3PO4 dropped to ≈6%, while Ag3PO4/UMOFNs(x) remained at ≈36%, which shows the inhibitory effect of UMOFNs on the photocorrosion of Ag3PO4. In addition, the radical scavenging experiment showed that *OH and *O2- were the most reactive species in the photocatalytic process.

MEMBROS DA BANCA:
Presidente - 756.483.183-91 - GERALDO EDUARDO DA LUZ JUNIOR - UESPI
Interno - 1553988 - EDSON CAVALCANTI DA SILVA FILHO
Interno - 050.406.403-74 - FRANCISCO XAVIER NOBRE - UFAM
Interno - 1714193 - JOSE MILTON ELIAS DE MATOS
Externo ao Programa - 028.021.083-36 - ROOSEVELT DELANO DE SOUSA BEZERRA - IFPI
Externo à Instituição - JOSE GERALDO DE ANDRADE PACHECO FILHO - UFPE