Highly Efficient Photocatalysts Based on Lamellar-Shaped Bi2S3 Grown on TiO2 Monolith

NANO ◽  
2018 ◽  
Vol 13 (09) ◽  
pp. 1850110
Author(s):  
Kaidi Li ◽  
Fangfang Zhang ◽  
Huiming Wang ◽  
Yalan Zhou ◽  
Lixin Zhao ◽  
...  

Here, the lamellar-shaped Bi2S3 grown on a porous TiO2 monolith was obtained by a two-step method including a sol–gel route and hydrothermal treatment. The photocatalytic activity of the as-synthesized Bi2S3/TiO2 composites was evaluated for photodegradation of methylene blue (MB) dye in aqueous solution under the visible-light irradiation. Based on our experimental results, 5% (molar ratio of Bi2S3 to TiO[Formula: see text] Bi2S3/TiO2 photocatalysts exhibited a maximum photodegradation rate of MB up to 96.9% under visible-light irradiation for 120 min. Our findings indicated that the lamellar-shaped Bi2S3 can extend the light absorption up to visible areas, and porous TiO2 can provide enhanced specific surface area and more mass transfer pathway to enhance the photodegradation efficiency. Furthermore, porous TiO2 can accept the electrons from the Bi2S3 conduction band due to the relatively positive electrode potential to impede the photoproduced electron and hole combination to result in advanced photocatalytic performance.

2018 ◽  
Vol 42 (13) ◽  
pp. 11109-11116 ◽  
Author(s):  
R. Salimi ◽  
A. A. Sabbagh Alvani ◽  
N. Naseri ◽  
S. F. Du ◽  
D. Poelman

A new plasmonic Ag hybridized CuWO4/WO3 heterostructured nanocomposite was successfully synthesized via a ligand-assisted sol gel method and the photocatalytic activity was evaluated by photo-degradation of methylene blue (MB) under visible light irradiation.


2019 ◽  
Vol 10 ◽  
pp. 1412-1422 ◽  
Author(s):  
Minlin Ao ◽  
Kun Liu ◽  
Xuekun Tang ◽  
Zishun Li ◽  
Qian Peng ◽  
...  

A BiOCl/TiO2/diatomite (BTD) composite was synthesized via a modified sol–gel method and precipitation/calcination method for application as a photocatalyst and shows promise for degradation of organic pollutants in wastewater upon visible-light irradiation. In the composite, diatomite was used as a carrier to support a layer of titanium dioxide (TiO2) nanoparticles and bismuth oxychloride (BiOCl) nanosheets. The results show that TiO2 nanoparticles and BiOCl nanosheets uniformly cover the surface of diatomite and bring TiO2 and BiOCl into close proximity. Rhodamine B was used as the target degradation product and visible light (λ > 400 nm) was used as the light source for the evaluation of the photocatalytic properties of the prepared BTD composite. The results show that the catalytic performance of the BTD composite under visible-light irradiation is much higher than that of TiO2 or BiOCl alone. When the molar ratio of BiOCl to TiO2 is 1:1 and the calcination temperature is 400 °C, the composite was found to exhibit the best catalytic effect. Through the study of the photocatalytic mechanism, it is shown that the strong visible-light photocatalytic activity of the BTD composite results mainly from the quick migration of photoelectrons from the conduction band of TiO2/diatomite to the surface of BiOCl, which promotes the separation effect and reduces the recombination rate of the photoelectron–hole pair. Due to the excellent catalytic performance, the BTD composite shows great potential for wide application in the field of sewage treatment driven by solar energy.


2015 ◽  
Vol 14 (3) ◽  
pp. 536-542 ◽  
Author(s):  
J. J. Macías-Sánchez ◽  
L. Hinojosa-Reyes ◽  
A. Caballero-Quintero ◽  
W. de la Cruz ◽  
E. Ruiz-Ruiz ◽  
...  

The photocatalytic performance of modified 30% wt. N-ZnO nanoparticles under visible light irradiation was demonstrated by the oxidation of picloram and 2,4-D.


2017 ◽  
Vol 53 (48) ◽  
pp. 6480-6483 ◽  
Author(s):  
Lu-Na Song ◽  
Lang Chen ◽  
Jie He ◽  
Peng Chen ◽  
Huang-Kai Zeng ◽  
...  

Bi self-doped Bi2MoO6–Bi2Mo3O12 composites were first synthesized by a one-step method and they showed excellent photocatalytic performance in the selective oxidation of aromatic alkanes under visible light irradiation.


Polymers ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 912
Author(s):  
Federica Costantino ◽  
Emanuele Cavaliere ◽  
Luca Gavioli ◽  
Riccardo Carzino ◽  
Luca Leoncino ◽  
...  

A photocatalytic system for the degradation of aqueous organic pollutants under visible light irradiation is obtained by an innovative approach based on ceria/platinum (Pt) hybrid nanoclusters on cellulose acetate fibrous membranes. The catalytic materials are fabricated by supersonic beam deposition of Pt nanoclusters directly on the surface of electrospun cellulose acetate fibrous mats, pre-loaded with a cerium salt precursor that is transformed into ceria nanoparticles directly in the solid mats by a simple thermal treatment. The presence of Pt enhances the oxygen vacancies on the surface of the formed ceria nanoparticles and reduces their band gap, resulting in a significant improvement of the photocatalytic performance of the composite mats under visible light irradiation. Upon the appropriate pretreatment and visible light irradiation, we prove that the most efficient mats, with both ceria nanoparticles and Pt nanoclusters, present a degradation efficiency of methylene blue of 70% and a photodegradation rate improved by about five times compared to the ceria loaded samples, without Pt. The present results bring a significant improvement of the photocatalytic performance of polymeric nanocomposite fibrous systems under visible light irradiation, for efficient wastewater treatment applications.


Crystals ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 756
Author(s):  
Zhengru Zhu ◽  
Songlin Han ◽  
Yongqiang Cao ◽  
Junchao Jiang

In this study, novel photocatalysts MVO4/g-C3N4 (M = La, Gd) were prepared by the hydrothermal method, through which different loading amounts of 10–50%MVO4 and g-C3N4 were mixed and ultrasonically oscillated to gain heterojunction catalysts. All the samples were characterized by XRD, SEM, TEM, FT-IR, XPS, Us-vis, and PL to ensure the successful integration of LaVO4 and GdVO4 with g-C3N4. The obtained results showed that MVO4/g-C3N4 could effectually improve the separation efficiency of photogenerated carriers during the photodegradation process, thus improving the photodegradation efficiency, while among them, 40%GdVO4/g-C3N4 showed the best photocatalytic performance and degradation of tetracycline hydrochloride, reaching up to 91% for 3 h, which was 3.64 times higher than pristine g-C3N4. From the discussed results above, the possible mechanism of the photodegradation process was put forward. This study supplies a promising method to gain g-C3N4-based photocatalysts for antibiotics removal.


Author(s):  
Snehamol Mathew ◽  
Priyanka Ganguly ◽  
Stephen Rhatigan ◽  
Vignesh Kumaravel ◽  
Ciara Byrne ◽  
...  

Indoor surface contamination by microbes is a major public health concern. A damp environment is one potential sources for microbe proliferation. Smart photocatalytic coatings on building surfaces using semiconductors like titania (TiO<sub>2</sub>) can effectively curb this growing threat.<b> </b>Metal-doped titania in anatase phase has been proved as a promising candidate for energy and environmental applications. In this present work, the antimicrobial efficacy of copper (Cu) doped TiO<sub>2 </sub>(Cu-TiO<sub>2</sub>) was evaluated against <i>Escherichia coli</i> (Gram-negative) and <i>Staphylococcus aureus</i> (Gram-positive) under visible light irradiation. Doping of a minute fraction of Cu (0.5 mol %) in TiO<sub>2 </sub>was carried out <i>via</i> sol-gel technique. Cu-TiO<sub>2</sub> further calcined at various temperatures (in the range of 500 °C – 700 °C) to evaluate the thermal stability of TiO<sub>2</sub> anatase phase. The physico-chemical properties of the samples were characterised through X-ray diffraction (XRD), Raman spectroscopy, X-ray photo-electron spectroscopy (XPS) and UV-visible spectroscopy techniques. XRD results revealed that the anatase phase of TiO<sub>2</sub> was maintained well, up to 650 °C, by the Cu dopant. UV-DRS results suggested that the visible light absorption property of Cu-TiO<sub>2 </sub>was enhanced and the band gap is reduced to 2.8 eV. Density functional theory (DFT) studies emphasises the introduction of Cu<sup>+</sup> and Cu<sup>2+</sup> ions by replacing Ti<sup>4+</sup> ions in the TiO<sub>2</sub> lattice, creating oxygen vacancies. These further promoted the photocatalytic efficiency. A significantly high bacterial inactivation (99.9%) was attained in 30 mins of visible light irradiation by Cu-TiO<sub>2</sub>.


2021 ◽  
Vol 50 (9) ◽  
pp. 3253-3260 ◽  
Author(s):  
Shan Zhao ◽  
Junbiao Wu ◽  
Yan Xu ◽  
Xia Zhang ◽  
Yide Han ◽  
...  

CdS/Ag2S/g-C3N4 ternary composites showed excellent photocatalytic performance toward H2 evolution. Their improved photocatalytic activity could be attributed not only to the synergic effect, but also to the introduction of Ag2S.


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