Banca de QUALIFICAÇÃO: RAFAEL LISANDRO PEREIRA ROCHA

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
DISCENTE: RAFAEL LISANDRO PEREIRA ROCHA
DATA: 31/01/2023
HORA: 14:00
LOCAL: auditório PPGCM
TÍTULO: Gallium-Containing Hydroxyapatite as a Promising Material for Photocatalytic Performance
PALAVRAS-CHAVES: hydroxyapatite; methylene blue; dye; discoloration; metal
PÁGINAS: 13
GRANDE ÁREA: Ciências Exatas e da Terra
ÁREA: Química
RESUMO:

The development of photocatalystsor their modification to obtain new photocatalytic performances for the removal of contaminants is a challenge. Hydroxyapatite (HAp), (Ca10(PO4)6(OH)2), is an inorganic component with a high superficial area and low toxicity and the presence of metal in its structure can be an interesting strategy for the photocatalytic approach. This work aimed to synthesize gallium-containing HAp (Ga-HAp) as a promising material for photocatalytic performance. The synthesis was performed by the suspension–precipitation method. The material was characterized by X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). Morphological analysis employed field emission scanning electron microscope (FESEM) and the elemental analysis by energy-dispersive spectroscopy (EDS). To evaluate the photocatalytic activity, methylene blue (MB) dye was used as a pollutant model under UV light for 120 min. The influence of Ga-HAp concentration (0.25, 0.50, and 1.00 g·L−1) and kinetic reaction was also studied. The Ga-HAp was successfully obtained by the suspension–precipitation method. The structural characterization by XRD and FESEM-EDS elucidated the presence of gallium in the structure of hydroxyapatite. The XPS results indicated the substitution of gallium in the crystal lattice of the material. The discoloration rate of MB dye using Ga-Hap was calculated by pseudo first-order kinetics, and the best rate constant was 7.5 × 10−3 min−1 using 1.00 g·L−1 of photocatalyst. The concentration of Ga-HAp influenced the photocatalytic process, because the discoloration rate increased as a function of the concentration of material. Therefore, Ga-HAp is a promising material for environmental remediation.

 https://doi.org/10.3390/min11121347

MEMBROS DA BANCA:
Presidente - 1722880 - JOSY ANTEVELI OSAJIMA FURTINI
Interno - 1553988 - EDSON CAVALCANTI DA SILVA FILHO
Interno - 1714193 - JOSE MILTON ELIAS DE MATOS
Externo ao Programa - 1731422 - JOAO SAMMY NERY DE SOUZA