Banca de DEFESA: GIRLENE GONÇALVES DO NASCIMENTO

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
DISCENTE : GIRLENE GONÇALVES DO NASCIMENTO
DATA : 19/07/2019
HORA: 09:00
LOCAL: Sala de aulas do PPGCEM
TÍTULO:

STUDY OF THE PHOTOCATALITIC AND PHOTOLUMINESCENT ACTIVITY OF MULTICAMATED CuO/ZnO FILES DEPOSITED BY SPIN COATING

PALAVRAS-CHAVES:

zinc oxide, copper oxide, polymeric precursors, photocatalysis, photoluminescence.

PÁGINAS: 111
GRANDE ÁREA: Engenharias
ÁREA: Engenharia de Materiais e Metalúrgica
SUBÁREA: Materiais Não-Metálicos
ESPECIALIDADE: Cerâmicos
RESUMO:

Recent studies investigate a new inorganic materials class which appears as a promising option for high performance applications in photoluminescence and photocatalysis field. Material development has opened new prospects of development photoluminescence and photocatalysis devices highly efficient which presented a particular relevance for reduction of effluent pollution from both industrial sources. Among the promising technological applications materials, the semiconductors ZnO and CuO stand out, due to a good performance of photocatalytic and optical properties. In this work, zinc oxide and copper oxide resins have been synthesized by polymeric precursors method, being deposited in multilayers on a silicon substrate, using the spin coating technique. The resins have been deposited in 6 layers ZnO/CuO; CuO/ZnO; CuO/CuO and ZnO/ZnO and, they have been heat-treated with temperatures 400ºC and 500ºC.The specimens were characterized by X-ray diffraction (DRX), UV/VIS spectroscopy, atomic force microscopy (AFM), scanning electron microscopy with field emission (MEV-FEG) and an energy dispersive X-ray spectrometer (EDS). The results of the X-ray analysis confirmed that there has been insufficient chemical interaction to form secondary stages among the oxides, in other words, multilayers have been formed. Absorption spectra UV/VIS characterized the thin as semiconductors, indicating optical gap from 1,53 eV to 3,35 eV. Scanning electron microscopy with field emission (MEV-FEG) showed films are homogenous and presented average pore size 25nm. Photoluminescent films emissions in multilayers change due to a decrease on the electronic recombination. Results of degradation from the cationic dye methylene blue show that pure films presents a diminished capacity compared to the films in the multilayers; and calcination at rising temperature and the increased of roughness improving catalytic performance of the films. The samples at multilayers CUZN400 and CUZN500 possessed the capability to degrade 98% of the blue dye in 120 minutes of sun exposition without addition of any other reagent to improve the photocatalytic capacity.

MEMBROS DA BANCA:
Interna - 1802888 - FABIANA VILLELA DA MOTTA
Externo à Instituição - JUAN ALBERTO CHAVEZ RUIZ - ISI-ER
Externa à Instituição - LAURENIA MARTINS PEREIRA GARCIA - UFRN
Presidente - 1883170 - MAURICIO ROBERTO BOMIO DELMONTE
Externo à Instituição - MAXYMME MENDES DE MELO - IFRN