Banca de QUALIFICAÇÃO: REBECCA ROBERTA YSRAELLE OLIVEIRA VERDE WILSON

Uma banca de QUALIFICAÇÃO de MESTRADO foi cadastrada pelo programa.
STUDENT : REBECCA ROBERTA YSRAELLE OLIVEIRA VERDE WILSON
DATE: 15/03/2024
TIME: 14:00
LOCAL: REMOTO
TITLE:

Optimization of the photocatalytic degradation of levofloxacin using the Bi2WO6/CuO heterostructure.

KEY WORDS:

Heterostructure; Photocatalysis; Bismuth Tungstate; Copper Oxide; Levofloxacin.

PAGES: 75
BIG AREA: Engenharias
AREA: Engenharia de Materiais e Metalúrgica
SUMMARY:

Industrial pollution on a global scale has had detrimental effects on aquatic life, releasing substantial amounts of harmful chemicals such as organic dyes, insecticides, and pharmaceuticals into the ecosystem. In response to this scenario, it becomes crucial to develop highly efficient photocatalytic materials with ease in the separation of photo-generated charges. Photocatalytic degradation, utilizing Advanced Oxidative Processes (AOPs), emerges as an adopted strategy to eliminate these contaminants, employing binary heterostructures as photocatalysts. This study synthesized Bi₂WO₆/CuO heterostructures with CuO mass compositions of 10%, 30%, and 50%, using microwave-assisted hydrothermal method. The heterostructures were characterized by XRD, FT-IR, and FE-SEM to assess their crystalline, vibrational, and morphological structures, respectively. The photocatalytic activity of the heterostructures (BWO/CuO) was evaluated under solar light irradiation for levofloxacin antibiotic degradation. XRD results indicated the formation of the orthorhombic phase of bismuth tungstate and monoclinic phase for copper oxide, as recorded in ICSD 024559 and ICSD 067850, respectively. No secondary phase formation occurred, suggesting successful heterostructure synthesis. FE-SEM micrographs revealed that pure BWO has a 3D flower-like morphology with nanoplates, while CuO exhibits fine nanosheet agglomerated structures. In the BWO/CuO heterostructure, BWO nanoplates form the matrix, accompanied by CuO nanosheets. FT-IR analysis indicated the absence of impurities, with heterostructure spectra showing characteristic peaks at 578 cm^-1, 497 cm^-1, 609 cm^-1, and 705 cm^-1, attributed to the presence of Cu–O, Bi–O, and W–O bonds. Egap results for BWO (3.27 eV) were higher than CuO (1.56 eV), and the bandgaps of BW/Cu-10 (3.16 eV), BW/Cu-30 (1.70 eV), and BW/Cu-50 (1.68 eV) heterostructures demonstrated a reduction compared to the Egap value of pure BWO. BW/Cu-10 exhibited the best photocatalytic performance, degrading 95% of levofloxacin antibiotic due to higher efficiency in separating photo-generated charges under solar irradiation.

COMMITTEE MEMBERS:
Presidente - 1802888 - FABIANA VILLELA DA MOTTA
Externo ao Programa - 1508681 - FELIPE BOHN - nullExterna à Instituição - LAURA XIMENA LOVISA - UNIFEI
Interno - 1883170 - MAURICIO ROBERTO BOMIO DELMONTE