Br-Doped Bi2O2CO3 exposed (001) crystal facets with enhanced photocatalytic activity

CrystEngComm ◽  
2017 ◽  
Vol 19 (34) ◽  
pp. 5001-5007 ◽  
Author(s):  
Jian Xu ◽  
Ke Ke Wang ◽  
Ting Liu ◽  
Yin Peng ◽  
Bin Gang Xu
Keyword(s):  
Photocatalytic Activity ◽  
Photocatalytic Performance ◽  
Synergistic Effects ◽  
Crystal Facet

Br-Doped Bi2O2CO3 exposed (001) facets were synthesized using CTAB as a surfactant and dopant. The highly enhanced photocatalytic performance of Br-doped Bi2O2CO3 is attributed to the synergistic effects of the doping of Br− and the active exposed (001) crystal facet.

Heterostructured g-C3N4/Ag–TiO2 composites with efficient photocatalytic performance under visible-light irradiation

RSC Advances ◽  
2015 ◽  
Vol 5 (69) ◽  
pp. 56136-56144 ◽  
Author(s):  
Mengqiao Zang ◽  
Lei Shi ◽  
Lin Liang ◽  
Defeng Li ◽  
Jianmin Sun
Keyword(s):  
Photocatalytic Activity ◽  
Visible Light ◽  
Visible Light Irradiation ◽  
Photocatalytic Performance ◽  
Synergistic Effects ◽  
High Photocatalytic Activity ◽  
Light Irradiation ◽  
Enhanced Absorption ◽  
Efficient Separation ◽  
Photogenerated Electrons

The heterostructured g-C3N4/Ag–TiO2 composites exhibited high photocatalytic activity, which was attributed to the synergistic effects of the enhanced absorption of visible light and the efficient separation rates for photogenerated electrons-holes.

scholarly journals Facile Green Synthesis of BiOBr Nanostructures with Superior Visible-Light-Driven Photocatalytic Activity

Materials ◽  
2018 ◽  
Vol 11 (8) ◽  
pp. 1273 ◽  
Author(s):  
Seema Garg ◽  
Mohit Yadav ◽  
Amrish Chandra ◽  
Sameer Sapra ◽  
Soniya Gahlawat ◽  
...  
Keyword(s):  
Photocatalytic Activity ◽  
Visible Light ◽  
Azadirachta Indica ◽  
Leaf Extract ◽  
Photocatalytic Performance ◽  
Synergistic Effects ◽  
High Specific Surface Area ◽  
Long Run ◽  
Solar Energy Harvesting ◽  
Plant Leaf Extract

Novel green bismuth oxybromide (BiOBr-G) nanoflowers were successfully synthesized via facile hydrolysis route using an Azadirachta indica (Neem plant) leaf extract and concurrently, without the leaf extract (BiOBr-C). The Azadirachta indica leaf extract was employed as a sensitizer and stabilizer for BiOBr-G, which significantly expanded the optical window and boosted the formation of photogenerated charge carriers and transfer over the BiOBr-G surface. The photocatalytic performance of both samples was investigated for the degradation of methyl orange (MO) and phenol (Ph) under the irradiation of visible light. The leaf extract mediated BiOBr-G photocatalyst displayed significantly higher photocatalytic activity when compared to BiOBr-C for the degradation of both pollutants. The degradation rate of MO and Ph by BiOBr-G was found to be nearly 23% and 16% more when compared to BiOBr-C under visible light irradiation, respectively. The substantial increase in the photocatalytic performance of BiOBr-G was ascribed to the multiple synergistic effects between the efficient solar energy harvesting, narrower band gap, high specific surface area, porosity, and effective charge separation. Furthermore, BiOBr-G displayed high stability for five cycles of photocatalytic activity, which endows its practical application as a green photocatalyst in the long run.

scholarly journals Synthesis of a Novel 1D/2D Bi2O2CO3–BiOI Heterostructure and Its Enhanced Photocatalytic Activity

Catalysts ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 1284
Author(s):  
Yin Peng ◽  
Haozhi Qian ◽  
Nannan Zhao ◽  
Yuan Li
Keyword(s):  
Photocatalytic Activity ◽  
Hydrothermal Method ◽  
Photocatalytic Performance ◽  
Raw Materials ◽  
Synergistic Effects ◽  
Two Dimensional ◽  
High Quality ◽  
Bioi Nanosheets

A novel 1D/2D Bi2O2CO3–BiOI heterojunction photocatalyst with high-quality interfaces was synthesized through a hydrothermal method by using Bi2O2CO3 nanorods and KI as raw materials. Two-dimensional (2D) BiOI nanosheets uniformly and vertically grow on the 1D porous Bi2O2CO3 rods. Bi2O2CO3–BiOI heterojunctions exhibit better photocatalytic activity than pure Bi2O2CO3 nanorods and BiOI nanosheets. Cr(VI) (30 mg/L), MO (20 mg/L) and BPA (20 mg/L) can be completely degraded in 8–15 min. The superior photocatalytic performance of 1D/2D Bi2O2CO3–BiOI heterojunction is ascribed to the synergistic effects: (a) vertical 2D on 1D multidimensional structure; (b) the formation of the Bi2O2CO3–BiOI p–n heterojunction; (c) high-quality interfaces between Bi2O2CO3 and BiOI.

scholarly journals Enhanced Photocatalytic Performance of Nitrogen-Doped TiO2 Nanotube Arrays Using a Simple Annealing Process

Micromachines ◽  
2018 ◽  
Vol 9 (12) ◽  
pp. 618 ◽  
Author(s):  
Phuoc Le ◽  
Le Hieu ◽  
Tu-Ngoc Lam ◽  
Nguyen Hang ◽  
Nguyen Truong ◽  
...  
Keyword(s):  
Photocatalytic Activity ◽  
Photocatalytic Performance ◽  
Synergistic Effects ◽  
Annealing Process ◽  
Tio2 Nanotube Arrays ◽  
Tio2 Nanotube ◽  
Nanotube Arrays ◽  
Doped Tio2 ◽  
Nitrogen Doped ◽  
N Doping

Nitrogen-doped TiO2 nanotube arrays (N-TNAs) were successfully fabricated by a simple thermal annealing process in ambient N2 gas at 450 °C for 3 h. TNAs with modified morphologies were prepared by a two-step anodization using an aqueous NH4F/ethylene glycol solution. The N-doping concentration (0–9.47 at %) can be varied by controlling N2 gas flow rates between 0 and 500 cc/min during the annealing process. Photocatalytic performance of as-prepared TNAs and N-TNAs was studied by monitoring the methylene blue degradation under visible light (λ ≥ 400 nm) illumination at 120 mW·cm−2. N-TNAs exhibited appreciably enhanced photocatalytic activity as compared to TNAs. The reaction rate constant for N-TNAs (9.47 at % N) reached 0.26 h−1, which was a 125% improvement over that of TNAs (0.115 h−1). The significant enhanced photocatalytic activity of N-TNAs over TNAs is attributed to the synergistic effects of (1) a reduced band gap associated with the introduction of N-doping states to serve as carrier reservoir, and (2) a reduced electron‒hole recombination rate.

Visible-Light Photocatalytic Activity of Fe and/or Ni Doped Ilmenite Derived-Titanium Dioxide Nanoparticles

2019 ◽  
Vol 19 (6) ◽  
pp. 3343-3355 ◽  
Author(s):  
Ge Li ◽  
Bao-Dong Wang ◽  
Qi Sun ◽  
Wayne-Qiang Xu ◽  
Yi-Fan Han
Keyword(s):  
Methylene Blue ◽  
Photocatalytic Activity ◽  
Visible Light ◽  
Metal Ions ◽  
Photocatalytic Performance ◽  
Synergistic Effects ◽  
Degradation Mechanism ◽  
Photocatalytic Decomposition ◽  
Precipitation Method ◽  
Single Type

Pure TiO2 nanoparticles and ones doped with Fe and/or Ni were successfully prepared by a co-precipitation method from ilmenite. The samples were structurally characterized by XRD, XPS, FT-IR, UV-vis, SEM, EDX, AAS and BET measurement. The XRD results showed that all samples were anatase TiO2, and no characteristic peaks of dopants were observed. The crystallite sizes of all doped TiO2 nanoparticles were less than 20 nm and doping TiO2 with metal ions can suppress the crystal growth of the particles. The XRD and XPS results indicated that TiO2 was uniformly doped and its crystalline phase was not changed by doping. The specific surface area of Fe–Ni/TiO2 is bigger than that of the un-doped TiO2. The pore size and pore volume of Fe–Ni/TiO2 is smaller than that of the un-doped. UV-vis spectra of the samples showed that the absorption edge red shifted with increasing doped metal content. The photocatalytic activity was evaluated in oxidative degradation of methylene blue (MB) with H2O2 under visible light irradiation. When doped with a single type of transition metal, the photocatalytic performance of Ni-doped samples was lower than that of Fe-doped ones. For the co-doped catalysts, the catalytic efficiency of 0.5%Fe4%Ni/TiO2 was the highest, reaching 93.34% after 250 min. Metal doping enhanced the photocatalytic decomposition of methylene blue compared with that of pure TiO2 by up to 1.5 times. The synergistic effects of the two metal ions improved the photocatalytic performance. The particles exhibited pronounced activity in degradation of MB as well as efficient recyclability. The photocatalytic degradation mechanism of methylene blue was analyzed.

Tuning the Photocatalytic Performance of Plasmonic Nanocomposites (ZnO/Aux) Driven in Visible Light

2019 ◽  
Vol 8 (1) ◽  
pp. 56-61
Author(s):  
Aneeya K. Samantara ◽  
Debasrita Dash ◽  
Dipti L. Bhuyan ◽  
Namita Dalai ◽  
Bijayalaxmi Jena
Keyword(s):  
Electron Transfer ◽  
Photocatalytic Activity ◽  
Visible Light ◽  
Transfer Rate ◽  
Photocatalytic Performance ◽  
Light Exposure ◽  
Au Nanoparticle ◽  
Electron Transfer Rate ◽  
Au Nps ◽  
Zno Nanostructure

: In this article, we explored the possibility of controlling the reactivity of ZnO nanostructures by modifying its surface with gold nanoparticles (Au NPs). By varying the concentration of Au with different wt% (x = 0.01, 0.05, 0.08, 1 and 2), we have synthesized a series of (ZnO/Aux) nanocomposites (NCs). A thorough investigation of the photocatalytic performance of different wt% of Au NPs on ZnO nanosurface has been carried out. It was observed that ZnO/Au0.08 nanocomposite showed the highest photocatalytic activity among all concentrations of Au on the ZnO surface, which degrades the dye concentration within 2 minutes of visible light exposure. It was further revealed that with an increase in the size of plasmonic nanoparticles beyond 0.08%, the accessible surface area of the Au nanoparticle decreases. The photon absorption capacity of Au nanoparticle decreases beyond 0.08% resulting in a decrease in electron transfer rate from Au to ZnO and a decrease of photocatalytic activity. Background: Due to the industrialization process, most of the toxic materials go into the water bodies, affecting the water and our ecological system. The conventional techniques to remove dyes are expensive and inefficient. Recently, heterogeneous semiconductor materials like TiO2 and ZnO have been regarded as potential candidates for the removal of dye from the water system. Objective: To investigate the photocatalytic performance of different wt% of Au NPs on ZnO nanosurface and the effect of the size of Au NPs for photocatalytic performance in the degradation process. Methods: A facile microwave method has been adopted for the synthesis of ZnO nanostructure followed by a reduction of gold salt in the presence of ZnO nanostructure to form the composite. Results: ZnO/Au0.08 nanocomposite showed the highest photocatalytic activity which degrades the dye concentration within 2 minutes of visible light exposure. The schematic mechanism of electron transfer rate was discussed. Conclusion: Raspberry shaped ZnO nanoparticles modified with different percentages of Au NPs showed good photocatalytic behavior in the degradation of dye molecules. The synergetic effect of unique morphology of ZnO and well anchored Au nanostructures plays a crucial role.

scholarly journals Enhanced Visible-Light Photocatalytic Performance of SAPO-5-Based g-C3N4 Composite for Rhodamine B (RhB) Degradation

Materials ◽  
2019 ◽  
Vol 12 (23) ◽  
pp. 3948
Author(s):  
Lingfang Qiu ◽  
Zhiwei Zhou ◽  
Mengfan Ma ◽  
Ping Li ◽  
Jinyong Lu ◽  
...  
Keyword(s):  
Photocatalytic Activity ◽  
Visible Light ◽  
Redox Reactions ◽  
Photocatalytic Performance ◽  
Dye Degradation ◽  
Thermal Polymerization ◽  
Light Illumination ◽  
Electron Hole ◽  
Visible Light Illumination ◽  
Visible Light Photocatalytic

Novel visible-light responded aluminosilicophosphate-5 (SAPO-5)/g-C3N4 composite has been easily constructed by thermal polymerization for the mixture of SAPO-5, NH4Cl, and dicyandiamide. The photocatalytic activity of SAPO-5/g-C3N4 is evaluated by degrading RhB (30 mg/L) under visible light illumination (λ > 420 nm). The effects of SAPO-5 incorporation proportion and initial RhB concentration on the photocatalytic performance have been discussed in detail. The optimized SAPO-5/g-C3N4 composite shows promising degradation efficiency which is 40.6% higher than that of pure g-C3N4. The degradation rate improves from 0.007 min−1 to 0.022 min−1, which is a comparable photocatalytic performance compared with other g-C3N4-based heterojunctions for dye degradation. The migration of photo-induced electrons from g-C3N4 to the Al site of SAPO-5 should promote the photo-induced electron-hole pairs separation rate of g-C3N4 efficiently. Furthermore, the redox reactions for RhB degradation occur on the photo-induced holes in the g-C3N4 and Al sites in SAPO-5, respectively. This achievement not only improves the photocatalytic activity of g-C3N4 efficiently, but also broadens the application of SAPOs in the photocatalytic field.

CdS/Ag2S/g-C3N4 ternary composites with superior photocatalytic performance for hydrogen evolution under visible light irradiation

2021 ◽  
Vol 50 (9) ◽  
pp. 3253-3260 ◽  
Author(s):  
Shan Zhao ◽  
Junbiao Wu ◽  
Yan Xu ◽  
Xia Zhang ◽  
Yide Han ◽  
...  
Keyword(s):  
Photocatalytic Activity ◽  
Visible Light ◽  
Hydrogen Evolution ◽  
Visible Light Irradiation ◽  
Photocatalytic Performance ◽  
Light Irradiation ◽  
Synergic Effect

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.

scholarly journals Photocatalytic Decolorization of Methyl Red on Nanoporous Anodic ZrO2 of Different Crystal Structures

Crystals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 215
Author(s):  
Ewa Wierzbicka ◽  
Karolina Syrek ◽  
Klaudia Mączka ◽  
Grzegorz D. Sulka
Keyword(s):  
Photocatalytic Activity ◽  
Photocatalytic Performance ◽  
Elevated Temperatures ◽  
Aqueous Electrolyte ◽  
High Surface ◽  
High Surface Area ◽  
Methyl Red ◽  
Self Organized ◽  
Photocatalytic Decolorization ◽  
Perfect Adhesion

High surface area, self-organized nanoporous ZrO2 arrays with perfect adhesion to the Zr substrate were synthesized by anodization in an aqueous electrolyte containing (NH4)2SO4 and NH4F. The obtained semiconductor materials were tested as photocatalysts for decolorization of the methyl red (MR) as a model azo dye pollutant. It was demonstrated that as-synthesized anodic ZrO2 anodic layers are already crystalline and, therefore, do not require further thermal treatment to provide a high photocatalytic performance. However, photocatalytic efficiency could be improved by annealing at a relatively low-temperature of 350 °C. Higher annealing temperatures caused a gradual drop of photocatalytic activity. The photocatalytic behavior was correlated with the crystal phase transformation in anodic ZrO2. It was found that higher photocatalytic activity was observed for the tetragonal phase over the monoclinic phase (predominant at elevated temperatures). It results from the optimal and complex electronic structure of annealed ZrO2 with three different energy states having absorption edges at 2.0, 4.01 and 5.28 eV.

The Study on the Influential Factors of Photocatalytic Performance of Eosin-Sensitized TiO2 Nanoparticles

2013 ◽  
Vol 827 ◽  
pp. 3-7
Author(s):  
Shun Jiang He ◽  
Xue Yan Du ◽  
Qiao Wang ◽  
Jing Xu
Keyword(s):  
Photocatalytic Activity ◽  
Methyl Orange ◽  
Photocatalytic Degradation ◽  
Degradation Rate ◽  
Photocatalytic Performance ◽  
Influential Factors ◽  
Sunlight Irradiation ◽  
Sensitization Time

The photocatalytic activity of eosin-sensitized TiO2 nanoparticles on photocatalytic degradation rate (PDR) of methyl orange under sunlight irradiation was studied. The influential factors on the degradation, such as eosin concentration, TiO2 dosage, sensitization time and sensitization temperature were also investigated. The results show that: The performance of TiO2 nanoparticles for PDR of methyl orange has been improved obviously for eosin sensitizing. The PDR of methyl orange reached 45.28% under the conditions of eosin concentration of 20mg/L, TiO2 dosage of 0.5000g/L, sensitization time of 24h and sensitization temperature of 20°C.

Sign in / Sign up

Export Citation Format

Share Document