Banca de QUALIFICAÇÃO: ANA GABRIELE DA COSTA SALES

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
DISCENTE: ANA GABRIELE DA COSTA SALES
DATA: 24/02/2026
HORA: 14:00
LOCAL: Auditório do PPGQ
TÍTULO: Hydrogen evolution coupled with sulfamethoxazole photodegradation over CuWO4-BiVO4 heterojunctions
PALAVRAS-CHAVES: Photoelectrochemical systems; antibiotic degradation; green hydrogen; photocatalysis; emergent pollutant; water splitting
PÁGINAS: 41
GRANDE ÁREA: Ciências Exatas e da Terra
ÁREA: Química
SUBÁREA: Físico-Química
ESPECIALIDADE: Cinética Química e Catálise
RESUMO:

The conversion of solar energy into chemical energy through photoelectrochemical (PEC) processes has emerged as a promising approach for renewable energy generation and environmental pollutant treatment. In this study, CuWO4-BiVO4 heterostructures were developed to enhance PEC system performance for simultaneous sulfamethoxazole (SMX) degradation and hydrogen production. The photoanodes were prepared using electrodeposition techniques, with CuWO4/BiVO4 and BiVO4/CuWO4 configurations. Structural characterization by X-ray diffraction and Raman spectroscopy confirmed the retention of individual oxide phases: monoclinic BiVO4 and triclinic CuWO4. Optical analysis revealed bandgaps of 2.55 eV for BiVO4 and 2.41 eV for CuWO4, suitable for efficient visible light absorption. The FTO|BiVO4/CuWO4 configuration achieved 100% SMX degradation within 180 minutes, with ~147 µmol hydrogen production and a Faradaic efficiency of 65-70%. The FTO|CuWO4/BiVO4 configuration produced ~133 µmol hydrogen with Faradaic efficiency of 40-45%. Electrochemical measurements showed that FTO|BiVO4/CuWO4 exhibited the highest photocurrent density and superior stability. Cyclic voltammetry data revealed enhanced hole extraction in the heterostructures, while electrochemical impedance spectroscopy indicated lower charge-transfer resistance for FTO|BiVO4/CuWO4, consistent with improved PEC performance. X-ray photoelectron spectroscopy analysis indicated well-preserved surface chemistry, with CuWO4 exhibiting a higher fraction of under-coordinated oxygen species, while photoluminescence spectra confirmed reduced recombination in the heterostructures. These results highlight the potential of CuWO4-BiVO4 heterostructures for efficient dual-functional PEC systems addressing both environmental remediation and energy generation. 

MEMBROS DA BANCA:
Presidente - 756.***.***-91 - GERALDO EDUARDO DA LUZ JUNIOR - UESPI
Interno - 1635927 - EDIVAN CARVALHO VIEIRA
Interno - 1714171 - JANILDO LOPES MAGALHAES
Interno - 1508806 - WELTER CANTANHEDE DA SILVA