Influence of microwave-assisted hydrothermal treatment time on the crystallinity, morphology and optical properties of ZnWO4 nanoparticles: Photocatalytic activity

Photocatalytic properties of the CeO2‐xTiO2 and TiO2‐xCeO2 (x = 10, 30, and 50 mol%) heterostructures obtained by a MAH

“…Concern regarding the generation of secondary waste after the photocatalytic process is necessary. Thus, the possibility of the material being used in more than one photocatalytic cycle without the need to apply complex and economically unfeasible methodologies is of paramount importance 55 . Reuse tests were performed so that the powder was separated after the photocatalytic process by centrifugation and dried.…”

A review on the applications of zinc tungstate (ZnWO4) photocatalyst for wastewater treatment

“…The ZnWO 4 nanoparticles synthesized in this manner were characterized, and the results obtained demonstrated the photocatalytic strength of nanoparticles in the degradation of both aqueous Rhodamine B (RhB) and Methylene Blue (MB) samples; the band gap and particle size were found to be 3.4 eV and 10 nm, respectively. Neto et al (2020) employed a microwave-assisted hydrothermal method, where ZnWO 4 nanoparticles were synthesized at 140 C and a pressure of 2 atm. This process involved using different concentrations of polyvinylpyrrolidone (PVP) as a precursor material.…”

“…In summary, ZnWO 4 has a wide range of applications in many other fields, such as humidity sensors (Arularasu and Sundaram, 2016), optical fibres (Ede et al, 2015), environmental decontamination and disinfection (He et al, 2020), microwave applications (He at al. 2016), photoluminescence (Kim et al, 2011), photovoltaic property (Neto et al, 2020), electrochemistry (Seong et al, 1993), photonics (Tang et al, 2014), catalysis (Yang et al, 2016a), supercapacitors (Yang et al, 2016b) and magnetic applications (Zhu et al, 2012). The ZnWO 4 as photodegradation and photoluminescence material has been a significant concern to researchers.…”

“…The Zn 2þ and WO 4 2ion concentration (M), Zn 2þ feed flow rate (mL/min) to the WO 4 2solution, and temperature obtained at these conditions were monoclinic with a hydrated structure. Time has also proven to be an essential factor to be considered when synthesizing nanoparticles, as Neto et al (2020) discovered that the crystallite size of a nanoparticle was greatly influenced by the increase in hydrothermal treatment time. It was also reported that increasing the time from 5 -120 min, the crystallite size went from 39.83 to 217.18 Å, the sample treated for 120 min exhibited the highest crystallization at 100 %, and after 120 min, there were no notable changes in the crystallinity of the ZnWO 4 nanoparticles at a treatment time higher than 120 min.…”

Estudo da degradação do pesticida fipronil utilizando heteroestruturas de semicondutores de BiVO4/CePO4 e CePO4/BiVO4

“…Segundo os métodos de síntese utilizados para a obtenção de heteroestruturas demonstrados na literatura [17][18][19][20][21][22][23], a proposta deste trabalho foi a combinação entre os métodos de coprecipitação (CP) seguida de tratamento hidrotérmico assistido por micro-ondas (THAM), a qual permite a obtenção de materiais puros, com alta homogeneidade, maior área superficial e em menor período de tempo. Além do mais, o crescimento e a nucleação podem ser controlados através de alterações de parâmetros como a concentração, a temperatura e o tempo, permitindo a obtenção de materiais com diferentes morfologias e com alta cristalinidade [20][21][22]. Desta forma, o presente trabalho teve como objetivo a síntese de heteroestruturas de BiVO 4 e CePO 4 utilizando a combinação entre os métodos de coprecipitação seguida de tratamento hidrotérmico assistido por micro-ondas e o estudo das propriedades fotocatalíticas frente à degradação do pesticida fipronil.…”