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Advanced Photocatalytic Materials

A special issue of Materials (ISSN 1996-1944). This special issue belongs to the section "Catalytic Materials".

Deadline for manuscript submissions: closed (31 December 2019) | Viewed by 38324

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Special Issue Editor

Section of Condensed Matter Physics, Department of Physics, National and Kapodistrian University of Athens, University Campus, GR-157 84 Zografou, Athens
Interests: photocatalytic materials; nanostructured titanium dioxide; carbon nanomaterials; metal oxides
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

Semiconductor photocatalysis has been established as a key technology to face global concerns over environmental pollution and ever-increasing energy demands through the utilization of environmentally benign materials and abundant, renewable energy sources such as solar energy.

This Special Issue targets the latest advances in photocatalytic materials for sustainable water/air remediation as well as hydrogen and chemical fuel production by photocatalytic water splitting and CO2 conversion, respectively. The unique potential of solar-powered technologies has spurred the development of nanostructured photocatalysts with improved structural, morphological and electronic properties that could effectively evade the two major limitations of process efficiency, i.e., the low quantum yield stemming from the recombination of photogenerated charge carriers and the poor visible light harvesting, pertinent mostly to wide band gap semiconductors such as the benchmark titanium dioxide (TiO2) photocatalysts. Emphasis will accordingly be placed on the design and fabrication of advanced photocatalytic materials relying on competent modification approaches such as coupling with plasmonic nanoparticles, surface engineering and judicious heterostructuring, as well as tailoring the materials’ structure and morphology (e.g. mesoporous materials and photonic crystals) in order to boost light harvesting and photon capture, charge separation and mass transfer, which play a pivotal role in photocatalytic environmental remediation and solar to chemical energy conversion applications.

I cordially invite you to contribute your recent work (review articles, original papers and communications) to this Special Issue on advanced photocatalytic materials for water/air pollutant degradation and solar fuels including, but not limited to, the following materials-oriented categories:

  • Visible light activated TiO2 nanomaterials;
  • Nanostructured metal oxide photocatalysts beyond TiO2;
  • Plasmonic photocatalysts;
  • Heterojunction (including Z-scheme) photocatalysts;
  • Graphene-based composite photocatalysts.

Assist. Prof. Dr. Vlassios Likodimos
Guest Editor

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Keywords

  • TiO2 nanomaterials
  • Plasmonic photocatalysts
  • Heterojunction photocatalysts
  • Meso-macroporous photocatalysts
  • Photonic crystals photocatalysts
  • Graphene photocatalysts
  • Water and air pollutant degradation
  • Solar fuels
  • Water splitting
  • Photocatalytic CO2 reduction

Published Papers (11 papers)

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Editorial

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3 pages, 184 KiB  
Editorial
Advanced Photocatalytic Materials
by Vlassis Likodimos
Materials 2020, 13(4), 821; https://doi.org/10.3390/ma13040821 - 11 Feb 2020
Cited by 8 | Viewed by 2942
Abstract
Semiconductor photocatalysts have attracted a great amount of multidiscipline research due to their distinctive potential for solar-to-chemical-energy conversion applications, ranging from water and air purification to hydrogen and chemical fuel production. This unique diversity of photoinduced applications has spurred major research efforts on [...] Read more.
Semiconductor photocatalysts have attracted a great amount of multidiscipline research due to their distinctive potential for solar-to-chemical-energy conversion applications, ranging from water and air purification to hydrogen and chemical fuel production. This unique diversity of photoinduced applications has spurred major research efforts on the rational design and development of photocatalytic materials with tailored structural, morphological, and optoelectronic properties in order to promote solar light harvesting and alleviate photogenerated electron-hole recombination and the concomitant low quantum efficiency. This book presents a collection of original research articles on advanced photocatalytic materials synthesized by novel fabrication approaches and/or appropriate modifications that improve their performance for target photocatalytic applications such as water (cyanobacterial toxins, antibiotics, phenols, and dyes) and air (NOx and volatile organic compounds) pollutant degradation, hydrogen evolution, and hydrogen peroxide production by photoelectrochemical cells. Full article
(This article belongs to the Special Issue Advanced Photocatalytic Materials)

Research

Jump to: Editorial

13 pages, 2309 KiB  
Article
Visible-Light Activated Titania and Its Application to Photoelectrocatalytic Hydrogen Peroxide Production
by Tatiana Santos Andrade, Ioannis Papagiannis, Vassilios Dracopoulos, Márcio César Pereira and Panagiotis Lianos
Materials 2019, 12(24), 4238; https://doi.org/10.3390/ma12244238 - 17 Dec 2019
Cited by 20 | Viewed by 2980
Abstract
Photoelectrochemical cells have been constructed with photoanodes based on mesoporous titania deposited on transparent electrodes and sensitized in the Visible by nanoparticulate CdS or CdS combined with CdSe. The cathode electrode was an air–breathing carbon cloth carrying nanoparticulate carbon. These cells functioned in [...] Read more.
Photoelectrochemical cells have been constructed with photoanodes based on mesoporous titania deposited on transparent electrodes and sensitized in the Visible by nanoparticulate CdS or CdS combined with CdSe. The cathode electrode was an air–breathing carbon cloth carrying nanoparticulate carbon. These cells functioned in the Photo Fuel Cell mode, i.e., without bias, simply by shining light on the photoanode. The cathode functionality was governed by a two-electron oxygen reduction, which led to formation of hydrogen peroxide. Thus, these devices were employed for photoelectrocatalytic hydrogen peroxide production. Two-compartment cells have been used, carrying different electrolytes in the photoanode and cathode compartments. Hydrogen peroxide production has been monitored by using various electrolytes in the cathode compartment. In the presence of NaHCO3, the Faradaic efficiency for hydrogen peroxide production exceeded 100% due to a catalytic effect induced by this electrolyte. Photocurrent has been generated by either a CdS/TiO2 or a CdSe/CdS/TiO2 combination, both functioning in the presence of sacrificial agents. Thus, in the first case ethanol was used as fuel, while in the second case a mixture of Na2S with Na2SO3 has been employed. Full article
(This article belongs to the Special Issue Advanced Photocatalytic Materials)
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19 pages, 4321 KiB  
Article
Carbon/Graphene-Modified Titania with Enhanced Photocatalytic Activity under UV and Vis Irradiation
by Kunlei Wang, Maya Endo-Kimura, Raphaëlle Belchi, Dong Zhang, Aurelie Habert, Johann Bouclé, Bunsho Ohtani, Ewa Kowalska and Nathalie Herlin-Boime
Materials 2019, 12(24), 4158; https://doi.org/10.3390/ma12244158 - 11 Dec 2019
Cited by 17 | Viewed by 2703
Abstract
Laser synthesis was used for one-step synthesis of titania/graphene composites (G-TiO2 (C)) from a suspension of 0.04 wt% commercial reduced graphene oxide (rGO) dispersed in liquid titanium tetraisopropoxide (TTIP). Reference titania sample (TiO2(C)) was prepared by the same method without [...] Read more.
Laser synthesis was used for one-step synthesis of titania/graphene composites (G-TiO2 (C)) from a suspension of 0.04 wt% commercial reduced graphene oxide (rGO) dispersed in liquid titanium tetraisopropoxide (TTIP). Reference titania sample (TiO2(C)) was prepared by the same method without graphene addition. Both samples and commercial titania P25 were characterized by various methods and tested under UV/vis irradiation for oxidative decomposition of acetic acid and dehydrogenation of methanol (with and without Pt co-catalyst addition), and under vis irradiation for phenol degradation and inactivation of Escherichia coli. It was found that both samples (TiO2(C) and G-TiO2(C)) contained carbon resulting from TTIP and C2H4 (used as a synthesis sensitizer), which activated titania towards vis activity. The photocatalytic activity under UV/vis irradiation was like that by P25. The highest activity of TiO2(C) sample for acetic acid oxidation was probably caused by its surface enrichment with hydroxyl groups. G-TiO2(C) was the most active for methanol dehydrogenation in the absence of platinum (ca. five times higher activity than that by TiO2(C) and P25), suggesting that graphene works as a co-catalyst for hydrogen evolution. High activity under both UV and vis irradiation for decomposition of organic compounds, hydrogen evolution and inactivation of bacteria suggests that laser synthesis allows preparation of cheap (carbon-modified) and efficient photocatalysts for broad environmental applications. Full article
(This article belongs to the Special Issue Advanced Photocatalytic Materials)
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16 pages, 3411 KiB  
Article
Silver-Copper Oxide Heteronanostructures for the Plasmonic-Enhanced Photocatalytic Oxidation of N-Hexane in the Visible-NIR Range
by Hugo Suarez, Adrian Ramirez, Carlos J. Bueno-Alejo and Jose L. Hueso
Materials 2019, 12(23), 3858; https://doi.org/10.3390/ma12233858 - 22 Nov 2019
Cited by 10 | Viewed by 3565
Abstract
Volatile organic compounds (VOCs) are recognized as hazardous contributors to air pollution, precursors of multiple secondary byproducts, troposphere aerosols, and recognized contributors to respiratory and cancer-related issues in highly populated areas. Moreover, VOCs present in indoor environments represent a challenging issue that need [...] Read more.
Volatile organic compounds (VOCs) are recognized as hazardous contributors to air pollution, precursors of multiple secondary byproducts, troposphere aerosols, and recognized contributors to respiratory and cancer-related issues in highly populated areas. Moreover, VOCs present in indoor environments represent a challenging issue that need to be addressed due to its increasing presence in nowadays society. Catalytic oxidation by noble metals represents the most effective but costly solution. The use of photocatalytic oxidation has become one of the most explored alternatives given the green and sustainable advantages of using solar light or low-consumption light emitting devices. Herein, we have tried to address the shortcomings of the most studied photocatalytic systems based on titania (TiO2) with limited response in the UV-range or alternatively the high recombination rates detected in other transition metal-based oxide systems. We have developed a silver-copper oxide heteronanostructure able to combine the plasmonic-enhanced properties of Ag nanostructures with the visible-light driven photoresponse of CuO nanoarchitectures. The entangled Ag-CuO heteronanostructure exhibits a broad absorption towards the visible-near infrared (NIR) range and achieves total photo-oxidation of n-hexane under irradiation with different light-emitting diodes (LEDs) specific wavelengths at temperatures below 180 °C and outperforming its thermal catalytic response or its silver-free CuO illuminated counterpart. Full article
(This article belongs to the Special Issue Advanced Photocatalytic Materials)
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12 pages, 1804 KiB  
Article
Photocatalytic Activity and Mechanical Properties of Cements Modified with TiO2/N
by Magdalena Janus, Szymon Mądraszewski, Kamila Zając, Ewelina Kusiak-Nejman, Antoni W. Morawski and Dietmar Stephan
Materials 2019, 12(22), 3756; https://doi.org/10.3390/ma12223756 - 14 Nov 2019
Cited by 24 | Viewed by 2657
Abstract
In this paper, studies of the mechanical properties and photocatalytic activity of new photoactive cement mortars are presented. The new building materials were obtained by the addition of 1, 3, and 5 wt % (based on the cement content) of nitrogen-modified titanium dioxide [...] Read more.
In this paper, studies of the mechanical properties and photocatalytic activity of new photoactive cement mortars are presented. The new building materials were obtained by the addition of 1, 3, and 5 wt % (based on the cement content) of nitrogen-modified titanium dioxide (TiO2/N) to the cement matrix. Photocatalytic active cement mortars were characterized by measuring the flexural and the compressive strength, the hydration heat, the zeta potential of the fresh state, and the initial and final setting time. Their photocatalytic activity was tested during NOx decomposition. The studies showed that TiO2/N gives the photoactivity of cement mortars during air purification with an additional positive effect on the mechanical properties of the hardened mortars. The addition of TiO2/N into the cement shortened the initial and final setting time, which was distinctly observed using 5 wt % of the photocatalyst in the cement matrix. Full article
(This article belongs to the Special Issue Advanced Photocatalytic Materials)
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22 pages, 9882 KiB  
Article
Microwave-Assisted Synthesis of High-Energy Faceted TiO2 Nanocrystals Derived from Exfoliated Porous Metatitanic Acid Nanosheets with Improved Photocatalytic and Photovoltaic Performance
by Yi-en Du, Xianjun Niu, Wanxi Li, Jing An, Yufang Liu, Yongqiang Chen, Pengfei Wang, Xiaojing Yang and Qi Feng
Materials 2019, 12(21), 3614; https://doi.org/10.3390/ma12213614 - 04 Nov 2019
Cited by 19 | Viewed by 3046
Abstract
A facile one-pot microwave-assisted hydrothermal synthesis of rutile TiO2 quadrangular prisms with dominant {110} facets, anatase TiO2 nanorods and square nanoprisms with co-exposed {101}/[111] facets, anatase TiO2 nanorhombuses with co-exposed {101}/{010} facets, and anatase TiO2 nanospindles with dominant {010} [...] Read more.
A facile one-pot microwave-assisted hydrothermal synthesis of rutile TiO2 quadrangular prisms with dominant {110} facets, anatase TiO2 nanorods and square nanoprisms with co-exposed {101}/[111] facets, anatase TiO2 nanorhombuses with co-exposed {101}/{010} facets, and anatase TiO2 nanospindles with dominant {010} facets were reported through the use of exfoliated porous metatitanic acid nanosheets as a precursor. The nanostructures and the formation reaction mechanism of the obtained rutile and anatase TiO2 nanocrystals from the delaminated nanosheets were investigated. The transformation from the exfoliated metatitanic nanosheets with distorted hexagonal cavities to TiO2 nanocrystals involved a dissolution reaction of the nanosheets, nucleation of the primary [TiO6]8− monomers, and the growth of rutile-type and anatase-type TiO2 nuclei during the microwave-assisted hydrothermal reaction. In addition, the photocatalytic activities of the as-prepared anatase nanocrystals were evaluated through the photocatalytic degradation of typical carcinogenic and mutagenic methyl orange (MO) under UV-light irradiation at a normal temperature and pressure. Furthermore, the dye-sensitized solar cell (DSSC) performance of the synthesized anatase TiO2 nanocrystals with various morphologies and crystal facets was also characterized. The {101}/[111]-faceted pH2.5-T175 nanocrystal showed the highest photocatalytic and photovoltaic performance compared to the other TiO2 samples, which could be attributed mainly to its minimum particle size and maximum specific surface area. Full article
(This article belongs to the Special Issue Advanced Photocatalytic Materials)
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19 pages, 5911 KiB  
Article
Effective Photocatalytic Activity of Sulfate-Modified BiVO4 for the Decomposition of Methylene Blue Under LED Visible Light
by Vinh Huu Nguyen, Quynh Thi Phuong Bui, Dai-Viet N. Vo, Kwon Taek Lim, Long Giang Bach, Sy Trung Do, Tuyen Van Nguyen, Van-Dat Doan, Thanh-Danh Nguyen and Trinh Duy Nguyen
Materials 2019, 12(17), 2681; https://doi.org/10.3390/ma12172681 - 22 Aug 2019
Cited by 21 | Viewed by 3660
Abstract
In this study, we investigated sulfate-modified BiVO4 with the high photocatalytic activity synthesized by a sol-gel method in the presence of thiourea, followed by the annealing process at different temperatures. Its structure was characterized by thermal gravimetric analysis (TGA), powder X-ray diffraction [...] Read more.
In this study, we investigated sulfate-modified BiVO4 with the high photocatalytic activity synthesized by a sol-gel method in the presence of thiourea, followed by the annealing process at different temperatures. Its structure was characterized by thermal gravimetric analysis (TGA), powder X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy/energy-dispersive X-ray spectroscopy (SEM/EDS), X-ray photoelectron spectroscopy (XPS), and ultraviolet-visible diffuse reflectance spectroscopy (UV-Vis DRS). The BiVO4 synthesized in the presence of thiourea and calcined at 600 °C (T-BVO-600) exhibited the highest photocatalytic degradation efficiency of methylene blue (MB) in water; 98.53% MB removal was achieved within 240 min. The reaction mechanisms that affect MB photocatalytic degradation on the T-BVO-600 were investigated via an indirect chemical probe method, using chemical agents to capture the active species produced during the early stages of photocatalysis, including 1,4-benzoquinone (scavenger for O2), ethylenediaminetetraacetic acid disodium salt (scavenger for h+), and tert-butanol (scavenger for HO). The results show that holes (h+) and hydroxyl radicals (HO) are the dominant species of MB decomposition. Photoluminescence (PL) measurement results of terephthalic acid solutions in the presence of BiVO4 samples and BiVO4 powders confirm the involvement of hydroxyl radicals and the separation efficiency of electron-hole pairs in MB photocatalytic degradation. Besides, the T-BVO-600 exhibits good recyclability for MB removal, achieving a removal rate of above 83% after five cycles. The T-BVO-600 has the features of high efficiency and good recyclability for MB photocatalytic degradation. These results provide new insight into the purpose of improving the photocatalytic activity of BiVO4 catalyst. Full article
(This article belongs to the Special Issue Advanced Photocatalytic Materials)
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11 pages, 5091 KiB  
Article
Incidence Dependency of Photonic Crystal Substrate and Its Application on Solar Energy Conversion: Ag2S Sensitized WO3 in FTO Photonic Crystal Film
by Xi Ke, Mengmeng Yang, Weizhe Wang, Dongxiang Luo and Menglong Zhang
Materials 2019, 12(16), 2558; https://doi.org/10.3390/ma12162558 - 11 Aug 2019
Cited by 7 | Viewed by 3338
Abstract
In addition to the most common applications of macroporous film: Supplying a large surface area, PC-FTO (macroporous fluorine-doped tin oxide with photonic crystal structure) can be employed as a template to control the morphologies of WO3 for exposing a more active facet, [...] Read more.
In addition to the most common applications of macroporous film: Supplying a large surface area, PC-FTO (macroporous fluorine-doped tin oxide with photonic crystal structure) can be employed as a template to control the morphologies of WO3 for exposing a more active facet, and enhance the overall photo-electron conversion efficiency for the embedded photoactive materials under changing illumination incidence through refracting and scattering. The optical features of PC-FTO film was demonstrated by DRUVS (diffuse reflectance UV-vis spectra). Plate-like WO3 were directly synthesized inside the PC-FTO film as a control group photoanode, Ag2S quantum dots were subsequently decorated on WO3 to tune the light absorption range. The impact of photonic crystal film on the photoactivity of Ag2S/WO3 was demonstrated by using the photoelectrochemical current density as a function of the incidence of the simulated light source. Full article
(This article belongs to the Special Issue Advanced Photocatalytic Materials)
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15 pages, 3543 KiB  
Article
Advanced Photocatalysts Based on Reduced Nanographene Oxide–TiO2 Photonic Crystal Films
by Angeliki Diamantopoulou, Elias Sakellis, Spiros Gardelis, Dimitra Tsoutsou, Spyridon Glenis, Nikolaos Boukos, Athanasios Dimoulas and Vlassis Likodimos
Materials 2019, 12(16), 2518; https://doi.org/10.3390/ma12162518 - 07 Aug 2019
Cited by 11 | Viewed by 3087
Abstract
Surface functionalization of TiO2 inverse opals by graphene oxide nanocolloids (nanoGO) presents a promising modification for the development of advanced photocatalysts that combine slow photon-assisted light harvesting, surface area, and mass transport of macroporous photonic structures with the enhanced adsorption capability, surface [...] Read more.
Surface functionalization of TiO2 inverse opals by graphene oxide nanocolloids (nanoGO) presents a promising modification for the development of advanced photocatalysts that combine slow photon-assisted light harvesting, surface area, and mass transport of macroporous photonic structures with the enhanced adsorption capability, surface reactivity, and charge separation of GO nanosheets. In this work, post-thermal reduction of nanoGO–TiO2 inverse opals was investigated in order to explore the role of interfacial electron transfer vs. pollutant adsorption and improve their photocatalytic activity. Photonic band gap-engineered TiO2 inverse opals were fabricated by the coassembly technique and were functionalized by GO nanosheets and reduced under He at 200 and 500 °C. Comparative performance evaluation of the nanoGO–TiO2 films on methylene blue photodegradation under UV-VIS and visible light showed that thermal reduction at 200 °C, in synergy with slow photon effects, improved the photocatalytic reaction rate despite the loss of nanoGO and oxygen functional groups, pointing to enhanced charge separation. This was further supported by photoluminescence spectroscopy and salicylic acid UV-VIS photodegradation, where, in the absence of photonic effects, the photocatalytic activity increased, confirming that fine-tuning of interfacial coupling between TiO2 and reduced nanoGO is a key factor for the development of highly efficient photocatalytic films. Full article
(This article belongs to the Special Issue Advanced Photocatalytic Materials)
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12 pages, 2270 KiB  
Article
TiO2 and Au-TiO2 Nanomaterials for Rapid Photocatalytic Degradation of Antibiotic Residues in Aquaculture Wastewater
by Tho Chau Minh Vinh Do, Duy Quoc Nguyen, Kien Trung Nguyen and Phuoc Huu Le
Materials 2019, 12(15), 2434; https://doi.org/10.3390/ma12152434 - 31 Jul 2019
Cited by 56 | Viewed by 5564
Abstract
Antibiotic residues in aquaculture wastewater are considered as an emerging environmental problem, as they are not efficiently removed in wastewater treatment plants. To address this issue, we fabricated TiO2 nanotube arrays (TNAs), TiO2 nanowires on nanotube arrays (TNWs/TNAs), Au nanoparticle (NP)-decorated-TNAs, [...] Read more.
Antibiotic residues in aquaculture wastewater are considered as an emerging environmental problem, as they are not efficiently removed in wastewater treatment plants. To address this issue, we fabricated TiO2 nanotube arrays (TNAs), TiO2 nanowires on nanotube arrays (TNWs/TNAs), Au nanoparticle (NP)-decorated-TNAs, and TNWs/TNAs, which were applied for assessing the photocatalytic degradation of eight antibiotics, simultaneously. The TNAs and TNWs/TNAs were synthesized by anodization using an aqueous NH4F/ethylene glycol solution. Au NPs were synthesized by chemical reduction method, and used to decorate on TNAs and TNWs/TNAs. All the TiO2 nanostructures exhibited anatase phase and well-defined morphology. The photocatalytic performance of TNAs, TNWs/TNAs, Au-TNAs and Au-TNWs/TNAs was studied by monitoring the degradation of amoxicillin, ampicillin, doxycycline, oxytetracycline, lincomycin, vancomycin, sulfamethazine, and sulfamethoxazole under ultraviolet (UV)-visible (VIS), or VIS illumination by LC-MS/MS method. All the four kinds of nanomaterials degraded the antibiotics effectively and rapidly, in which most antibiotics were removed completely after 20 min treatment. The Au-TNWs/TNAs exhibited the highest photocatalytic activity in degradation of the eight antibiotics. For example, reaction rate constants of Au-TNWs/TNAs for degradation of lincomycin reached 0.26 min−1 and 0.096 min−1 under UV-VIS and VIS irradiation, respectively; and they were even higher for the other antibiotics. The excellent photocatalytic activity of Au-TNWs/TNAs was attributed to the synergistic effects of: (1) The larger surface area of TNWs/TNAs as compared to TNAs, and (2) surface plasmonic effect in Au NPs to enhance the visible light harvesting. Full article
(This article belongs to the Special Issue Advanced Photocatalytic Materials)
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18 pages, 5891 KiB  
Article
Photodegradation of Microcystin-LR Using Visible Light-Activated C/N-co-Modified Mesoporous TiO2 Photocatalyst
by Tamer M. Khedr, Said M. El-Sheikh, Adel A. Ismail, Ewa Kowalska and Detlef W. Bahnemann
Materials 2019, 12(7), 1027; https://doi.org/10.3390/ma12071027 - 28 Mar 2019
Cited by 24 | Viewed by 3800
Abstract
Microcystin-LR (MC-LR), a potent hepatotoxin produced by the cyanobacteria, is of increasing concern worldwide because of severe and persistent impacts on humans and animals by inhalation and consumption of contaminated waters and food. In this work, MC-LR was removed completely from aqueous solution [...] Read more.
Microcystin-LR (MC-LR), a potent hepatotoxin produced by the cyanobacteria, is of increasing concern worldwide because of severe and persistent impacts on humans and animals by inhalation and consumption of contaminated waters and food. In this work, MC-LR was removed completely from aqueous solution using visible-light-active C/N-co-modified mesoporous anatase/brookite TiO2 photocatalyst. The co-modified TiO2 nanoparticles were synthesized by a one-pot hydrothermal process, and then calcined at different temperatures (300, 400, and 500 °C). All the obtained TiO2 powders were analyzed by X-ray diffraction (XRD), Raman spectroscopy, transmission electron microscope (TEM), specific surface area (SSA) measurements, ultraviolet-visible diffuse reflectance spectra (UV-vis DRS), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared (FTIR) spectroscopy, and photoluminescence (PL) analysis. It was found that all samples contained mixed-phase TiO2 (anatase and brookite), and the content of brookite decreased with an increase in calcination temperature, as well as the specific surface area and the content of non-metal elements. The effects of initial pH value, the TiO2 content, and MC-LR concentration on the photocatalytic activity were also studied. It was found that the photocatalytic activity of the obtained TiO2 photocatalysts declined with increasing temperature. The complete degradation (100%) of MC-LR (10 mg L−1) was observed within 3 h, using as-synthesized co-modified TiO2 (0.4 g L−1) at pH 4 under visible light. Based on the obtained results, the mechanism of MC-LR degradation has been proposed. Full article
(This article belongs to the Special Issue Advanced Photocatalytic Materials)
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