@Article{MoraesBSSMCTR:2019:EfCaCo,
author = "Moraes, Nicolas Perciani and Bacetto, Let{\'{\i}}cia Araujo and
Santos, Gabriela Spirandelli dos and Silva, Maria Lucia Caetano
Pinto da and Machado, Jo{\~a}o Paulo Barros and Campos, Tiago
Moreira Bastos and Thim, Gilmar Patroc{\'{\i}}nio and Rodrigues,
Liana Alvares",
affiliation = "{Universidade de S{\~a}o Paulo (USP)} and {Universidade de
S{\~a}o Paulo (USP)} and {Universidade de S{\~a}o Paulo (USP)}
and {Universidade de S{\~a}o Paulo (USP)} and {Instituto Nacional
de Pesquisas Espaciais (INPE)} and {Instituto Tecnol{\'o}gico de
Aeron{\'a}utica (ITA)} and {Instituto Tecnol{\'o}gico de
Aeron{\'a}utica (ITA)} and {Universidade de S{\~a}o Paulo
(USP)}",
title = "Synthesis of novel ZnO/carbon xerogel composites: Effect of carbon
content and calcination temperature on their structural and
photocatalytic properties",
journal = "Ceramics International",
year = "2019",
volume = "45",
number = "3",
pages = "3657--3667",
month = "Feb.",
keywords = "Zinc oxide, Photocatalysis, Carbon xerogel, Tannin, Methylene
blue.",
abstract = "This paper reports the development of new ZnO/carbon xerogel
composites (XZn w) for photocatalytic applications. The use of
black wattle tannin as a precursor to the carbon xerogel aimed at
reducing costs and environmental impacts. The composites were
characterized by diffuse reflectance spectroscopy (DRS), BET
surface area, scanning electron microscopy (FEG-SEM), X-ray
photoelectron spectroscopy (XPS), energy dispersive spectroscopy
(EDS), infrared spectroscopy (IR), and X-ray diffraction (XRD).
The photocatalytic performance of the materials was evaluated in
the decomposition process of methylene blue, a known toxic
pollutant. The impacts of the catalyst dosage and calcination
temperature on the photocatalytic process were also examined
systematically. The X-ray profiles of the XZn w evidenced the
existence of the hexagonal structure of the zinc oxide (wurtzite)
in the composites. The XPS and XRD analyses confirmed the
incorporation of carbon in the zinc oxide crystalline structure.
The higher carbon content resulted in a larger surface area. All
composites presented the ability to absorb radiation in less
energetic wavelengths, contrary to pure zinc oxide that only
absorbs radiation of wavelengths below 420 nm. The optimal dosage
and calcination temperature were found to be 0.2 g L\−1 and
300 °C. All the developed composites displayed significant
photocatalytic activities in the decomposition of methylene blue
under both visible and solar light. The composites had superior
photocatalytic efficiency under visible light when compared to
pure zinc oxide. The XZn 0.5 presented the best degradation
efficiency under visible radiation. All materials presented
similar photocatalytic responses under solar light, evidencing the
synergy between the carbon xerogel and the zinc oxide. The
photocatalytic mechanism was evaluated by trapping experiments to
be mainly controlled by the electron vacancies that are generated
during the photoexcitation of the composites.",
doi = "10.1016/j.ceramint.2018.11.027",
url = "http://dx.doi.org/10.1016/j.ceramint.2018.11.027",
issn = "0272-8842",
language = "en",
targetfile = "moraes_synthesis.pdf",
urlaccessdate = "27 abr. 2024"
}