scholarly journals Ceria doping boosts methylene blue photodegradation in titania nanostructures

Author(s):  
Chiara Alberoni ◽  
Isabel Barroso-Martín ◽  
Antonia Infantes-Molina ◽  
Enrique Rodríguez-Castellón ◽  
Aldo Talon ◽  
...  

The photocatalytic activity of titania nanotubes and nanoparticles toward methylene blue (MB) can be enhanced through addition of a small amount of Ce. MB acts as a hole scavenger, fastening the photocatalytic process.

2011 ◽  
Vol 295-297 ◽  
pp. 1433-1435
Author(s):  
Yan Li Ma ◽  
Gui Zhen Fang ◽  
Cheng Liu

(Tetracarboxyphthalocyaninato) cobalt (Ⅱ) was used as dye to enhance the photocatalytic activity of nano-TiO2 in visible light. The photocatalyzer was prepared by phthlocyanine Co and TiO2, which was called TPC. The photocatalytic process of removal of benzene was investigated in visible light and ultraviolet. Results reveal that TPC can enhance photocatalytic activity of TiO2. The Benzene removal of TPC catalyst at 4.5 h was 52.80 % in incandescent lamp, at the same time it was 41.86% higher than nano-TiO2. The Benzene removal of TPC catalyst at 4.5 h was 43.53% in fluorescent lamp, at then 28.03% higher than nano-TiO2. The Benzene removal of TPC catalyst at 4.5 h was 36.58% under ultraviolet, at then 5.50% lower than nano-TiO2. The Benzene removal of TPC catalyst at 4.5 h was 10.69% in incandescent lamp, at then 2.15% higher than nano-TiO2. TPC catalyst should enhance ability of liquid photocatalytic oxidation TiO2. The highest photocatalytic degradation of nitrobenzene and methylene blue were separately 76.60 % and 21.02 % under incandescent light.


2014 ◽  
Vol 665 ◽  
pp. 284-287
Author(s):  
Guang Bi Li ◽  
Chun Zheng Song ◽  
Jin Li Zhang ◽  
Sheng Yan Tian

TiO2 nanotubes (TNTs) was prepared by hydrothermal method using commercial P25 power as a precursor in alkali solution and was characterized by TEM, XRD and BET. The photocatalytic activity of TNTs was evaluated by degradation of methylene blue (MB). The as-prepared TNTs hydrothermal treated at 150 °C displayed higher photodegradation activity. These results provide further insight into the effect of hydrothermal temperature, and TNTs are expected to be promising for applications in photocatalysis.


2018 ◽  
Vol 18 (3) ◽  
pp. 81-91 ◽  
Author(s):  
C. Lalhriatpuia

Nanopillars-TiO2 thin films was obtained on a borosilicate glass substrate with (S1) and without (S2) polyethylene glycol as template. The photocatalytic behaviour of S1 and S2 thin films was assessed inthe degradation of methylene blue (MB) dye from aqueous solution under batch reactor operations. The thin films were characterized by the SEM, XRD, FTIR and AFM analytical methods. BET specific surface area and pore sizes were also obtained. The XRD data confirmed that the TiO2 particles are in its anatase mineral phase. The SEM and AFM images indicated the catalyst is composed with nanosized pillars of TiO2, evenly distributed on the surface of the substrate. The BET specific surface area and pore sizes of S1 and S2 catalyst were found to be 5.217 and 1.420 m2/g and 7.77 and 4.16 nm respectively. The photocatalytic degradation of MB was well studied at wide range of physico-chemical parameters. The effect of solution pH (pH 4.0 to 10.0) and MB initial concentration (1.0 to 10.0 mg/L) was extensively studied and the effect of several interfering ions, i.e., cadmium nitrate, copper sulfate, zinc chloride, sodium chloride, sodium nitrate, sodium nitrite, glycine, oxalic acid and EDTA in the photocatalytic degradation of MB was demonstrated. The maximum percent removal of MB was observed at pH 8.0 beyond which it started decreasing and a low initial concentration of the pollutant highly favoured the photocatalytic degradation using thin films and the presence of several interfering ions diminished the photocatalytic activity of thin films to some extent. The overall photocatalytic activity was in the order: S2 > S1 > UV. The photocatalytic degradation of MB was followed the pseudo-first-order rate kinetics. The mineralization of MB was studied with total organic carbon measurement using the TOC (total organic carbon) analysis.


Materials ◽  
2021 ◽  
Vol 14 (8) ◽  
pp. 1985
Author(s):  
Irina Plesco ◽  
Vladimir Ciobanu ◽  
Tudor Braniste ◽  
Veaceslav Ursaki ◽  
Florian Rasch ◽  
...  

A new type of photocatalyst is proposed on the basis of aero-β-Ga2O3, which is a material constructed from a network of interconnected tetrapods with arms in the form of microtubes with nanometric walls. The aero-Ga2O3 material is obtained by annealing of aero-GaN fabricated by epitaxial growth on ZnO microtetrapods. The hybrid structures composed of aero-Ga2O3 functionalized with Au or Pt nanodots were tested for the photocatalytic degradation of methylene blue dye under UV or visible light illumination. The functionalization of aero-Ga2O3 with noble metals results in the enhancement of the photocatalytic performances of bare material, reaching the performances inherent to ZnO while gaining the advantage of the increased chemical stability. The mechanisms of enhancement of the photocatalytic properties by activating aero-Ga2O3 with noble metals are discussed to elucidate their potential for environmental applications.


2021 ◽  
Vol 78 (5) ◽  
pp. 2849-2865
Author(s):  
Bircan Haspulat Taymaz ◽  
Recep Taş ◽  
Handan Kamış ◽  
Muzaffer Can

Catalysts ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 589
Author(s):  
Sivagowri Shanmugaratnam ◽  
Balaranjan Selvaratnam ◽  
Aravind Baride ◽  
Ranjit Koodali ◽  
Punniamoorthy Ravirajan ◽  
...  

Earth–abundant transition metal chalcogenide materials are of great research interest for energy production and environmental remediation, as they exhibit better photocatalytic activity due to their suitable electronic and optical properties. This study focuses on the photocatalytic activity of flower-like SnS2 nanoparticles (composed of nanosheet subunits) embedded in TiO2 synthesized by a facile hydrothermal method. The materials were characterized using different techniques, and their photocatalytic activity was assessed for hydrogen evolution reaction and the degradation of methylene blue. Among the catalysts studied, 10 wt. % of SnS2 loaded TiO2 nanocomposite shows an optimum hydrogen evolution rate of 195.55 µmolg−1, whereas 15 wt. % loading of SnS2 on TiO2 exhibits better performance against the degradation of methylene blue (MB) with the rate constant of 4.415 × 10−4 s−1 under solar simulated irradiation. The improved performance of these materials can be attributed to the effective photo-induced charge transfer and reduced recombination, which make these nanocomposite materials promising candidates for the development of high-performance next-generation photocatalyst materials. Further, scavenging experiments were carried out to confirm the reactive oxygen species (ROS) involved in the photocatalytic degradation. It can be observed that there was a 78% reduction in the rate of degradation when IPA was used as the scavenger, whereas around 95% reduction was attained while N2 was used as the scavenger. Notably, very low degradation (<5%) was attained when the dye alone was directly under solar irradiation. These results further validate that the •OH radical and the superoxide radicals can be acknowledged for the degradation mechanism of MB, and the enhancement of degradation efficiency may be due to the combined effect of in situ dye sensitization during the catalysis and the impregnation of low bandgap materials on TiO2.


Catalysts ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 117
Author(s):  
Zahir Muhammad ◽  
Farman Ali ◽  
Muhammad Sajjad ◽  
Nisar Ali ◽  
Muhammad Bilal ◽  
...  

Degradation of organic dyes and their byproducts by heterogeneous photocatalysts is an essential process, as these dyes can be potentially discharged in wastewater and threaten aquatic and xerophyte life. Therefore, their complete mineralization into nontoxic components (water and salt) is necessary through the process of heterogeneous photocatalysis. In this study, Zr/CrO2 (Zirconium-doped chromium IV oxide) nanocomposite-based photocatalysts with different compositions (1, 3, 5, 7 & 9 wt.%) were prepared by an environmentally friendly, solid-state reaction at room temperature. The as-prepared samples were calcined under air at 450 °C in a furnace for a specific period of time. The synthesis of Zr/CrO2 photocatalysts was confirmed by various techniques, including XRD, SEM, EDX, FT-IR, UV-Vis, and BET. The photocatalytic properties of all samples were tested towards the degradation of methylene blue and methyl orange organic dyes under UV light. The results revealed a concentration-dependent photocatalytic activity of photocatalysts, which increased the amount of dopant (up to 5 wt.%). However, the degradation efficiency of the catalysts decreased upon further increasing the amount of dopant due to the recombination of holes and photoexcited electrons.


RSC Advances ◽  
2020 ◽  
Vol 10 (39) ◽  
pp. 23024-23037 ◽  
Author(s):  
Fengxia Zhang ◽  
Wenjing Li ◽  
Tianyi Jiang ◽  
Xuemei Li ◽  
Yuanyuan Shao ◽  
...  

Three novel visible-light-driven composite photocatalysts were synthesized by hydrothermal method. The effects of introducing PDIs with different structures into TiO2 were evaluated by assaying the photodegradation rate of methylene blue.


2019 ◽  
Vol 56 ◽  
pp. 152-157 ◽  
Author(s):  
Abdelouahab Noua ◽  
Hichem Farh ◽  
Rebai Guemini ◽  
Oussama Zaoui ◽  
Tarek Diab Ounis ◽  
...  

Nickel oxide (NiO) thin films were successfully deposited by sol-gel dip-coating method on glass substrates. The structural, morphological and optical properties in addition to the photocatalytic activity of the prepared films were investigated. The results show that the films have a polycrystalline NiO cubic structure with dense NiO grains and average optical transmittance in the visible region. The photocatalytic properties of the films were studied through the degradation of methylene blue and 89% of degradation was achieved for 4.5h of solar light irradiation exposure which indicates the capability of NiO photocatalytic activity.


Sign in / Sign up

Export Citation Format

Share Document