Banca de DEFESA: BÁRBARA SCOLA RODRIGUES

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
DISCENTE : BÁRBARA SCOLA RODRIGUES
DATA : 05/02/2024
HORA: 13:00
LOCAL: Sala 303 do Bloco B do Campus de Santo André da Universidade Federal do ABC
TÍTULO:

Photoactive devices based on heterojunctions of bismuth vanadate and tungsten oxide over graphene

PÁGINAS: 368
RESUMO:

Bismuth vanadate (BiVO4) stands out as a highly promising material for solar-driven hydrogen production due to its unique properties, but its high recombination rates limit its use as a photocatalyst. Strategies such as tungsten-doping and forming a heterojunction with tungsten oxide (WO3) are considered to enhance its performance. The optimization of photoactive devices relies on properties like crystalline structure and the heterojunction interface. Additionally, devices can be optimized by adding a highly conductive material that assists in charge transfer, such as graphene oxide (GO).This study focuses on fabricating photoanodes based on tungsten-doped BiVO4 and WO3 heterojunctions onto graphene oxide (GO), using microwave-assisted synthesis for rapid processes. Microwave assisted synthesis represents a potent technique, drastically accelerating the synthesis process. However, the impact of synthetic parameters on microwave-assisted synthesis remains underexplored for many systems.Considering that, this work proposes corelations between properties od the resulting materials and the synthesis conditions. In the case of (W)BiVO4, the choice of solvent was crucial for controlling morphology and crystalline structure. Additionally, tungsten doping and reduced synthesis time proved effective in enhancing photocatalytic activity. As a result, hierarchical structures of W-BiVO4 (prepared in ethylene glycol) / WO3 exhibited a photocurrent 16 times higher than W-BiVO4 (prepared in ethanol) / WO3 for the oxygen evolution reaction (OER). WO3 was modified with GO in a one-pot microwave synthesis, where the crucial effect of the microwave cavity on material properties was observed. Photoactive WO3/GO heterojunctions with adjustable crystalline structure were obtained by altering temperature and synthesis time. The results demonstrated that it is possible to modulate the properties and efficiency of photocatalysts through fine-tuning microwave conditions.

MEMBROS DA BANCA:
Presidente - Interno ao Programa - 2351974 - JULIANA DOS SANTOS DE SOUZA
Membro Titular - Examinador(a) Interno ao Programa - 1601156 - WAGNER ALVES CARVALHO
Membro Titular - Examinador(a) Interno ao Programa - 1838759 - JANAINA DE SOUZA GARCIA
Membro Titular - Examinador(a) Externo à Instituição - ITALO ODONE MAZALI
Membro Titular - Examinador(a) Externo à Instituição - THIAGO DE CARVALHO CIPRIANO - SENAI INOV
Membro Suplente - Examinador(a) Interno ao Programa - 1844792 - AMEDEA BAROZZI SEABRA
Membro Suplente - Examinador(a) Externo ao Programa - 1734908 - FABIO FURLAN FERREIRA
Membro Suplente - Examinador(a) Externo à Instituição - MARIA VALNICE BOLDRIN