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Photocatalytic Degradation of Organic Wastes in Water
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Photocatalytic Degradation of Organic Wastes in Water

A special issue of Catalysts (ISSN 2073-4344). This special issue belongs to the section "Photocatalysis".

Deadline for manuscript submissions: closed (31 March 2021) | Viewed by 46359

Special Issue Editors

Prof. Dr. Maria Victoria López Ramón

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Guest Editor
Department of Inorganic and Organic Chemistry, Faculty of Experimental Science, University of Jaén, 23071 Jaén, Spain
Interests: carbon materials; catalytic and photocatalytic materials; water treatment; adsorption; advanced oxidation processes; photocatalysis; UV/solar radiation; nanotechnology
Special Issues, Collections and Topics in MDPI journals
Prof. Dr. José Rivera-Utrilla

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Guest Editor
Facultad de Ciencias, Departamento de Química Inorgánica, Universidad de Granada, E-18071 Granada, Spain
Interests: preparation of new nanostructured carbon materials as catalysts and photocatalysts to develop advanced water treatments; removal of pollutants from aqueous and gaseous phases by adsorption/bioadsorption/biodegradation processes and catalysis using advanced carbon materials; new treatments of water contaminated by organic pollutants by integrated technologies based on advanced oxidation/reduction processes (ozonation, photooxidation, radiolysis) and carbon materials
Prof. Dr. Manuel Sánchez-Polo

E-Mail Website
Guest Editor
Department of Inorganic Chemistry, Faculty of Pharmacy, University of Granada, Granada, Spain
Interests: advance oxidation processes; water/wastewater treatment; adsorption; materials synthesis; bioadsorption; air and soil treatment; (photo) catalysis
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

In recent years, public concerns have arisen about environmental pollution by so-called emerging organic pollutants (EOPS) in water sources and factory effluents, because of their potentially adverse effects on human health and aquatic ecosystems. A large number of physical and biological processes have been proposed to remove pollutants from water, but they do not completely remove the majority of EOPs. Advanced oxidation processes (AOPs) based on catalytic, electrochemical, and photochemical reactions are currently available and are able to degrade a large number of pollutants. An important group of AOPs is represented by photocatalytic processes, in which luminous radiation produces the electronic activation of the semiconductor material that constitutes the catalyst. TiO2 is one of the most widely applied materials as photocatalysts in water decontamination, both alone and in combination with other materials acting as doping agents and/or material supports. However, the use of this semiconductor material presents known disadvantages; therefore, it is very important to continue working on the search for new, more efficient photocatalysts with better performance.
This Special Issue on “Photocatalytic Degradation of Organic Wastes in Water” is intended to cover the progresses and new trends in the preparation and characterization of photocatalytic materials, with particular emphasis on their applications in environmental remediation for the removal of emerging organic pollutans from different types of water.

Prof. Dr. José Rivera-Utrilla
Prof. María V. López-Ramón
Prof. Dr. Manuel Sánchez-Polo
Guest Editor

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Keywords

  • Photocatalysts design and synthesis
  • photoactivity
  • UV/visible light
  • solar light
  • organic pollutants
  • reaction kinetics and mechanism
  • stability and reusability
  • degradation by-products
  • environmental applications
  • water treatments

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Published Papers (12 papers)

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Editorial

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4 pages, 204 KiB  
Editorial
Photocatalytic Degradation of Organic Wastes in Water
by María Victoria López-Ramón, José Rivera-Utrilla and Manuel Sánchez-Polo
Catalysts 2022, 12(2), 114; https://doi.org/10.3390/catal12020114 - 19 Jan 2022
Cited by 1 | Viewed by 1777
Abstract
Over recent years, public concerns have arisen about environmental pollution by so-called emerging organic pollutants (EOPs) in water sources and factory effluents, because of their potentially adverse effects on human health and aquatic ecosystems [...] Full article
(This article belongs to the Special Issue Photocatalytic Degradation of Organic Wastes in Water)

Research

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16 pages, 8992 KiB  
Article
Assembly of CaIn2S4 on Defect-Rich BiOCl for Acceleration of Interfacial Charge Separation and Photocatalytic Phenol Degradation via S-Scheme Electron Transfer Mechanism
by Zhuangzhuang Zhang, Yuanyuan Zhang, Xuanxuan Han, Li Guo, Danjun Wang and Kangle Lv
Catalysts 2021, 11(9), 1130; https://doi.org/10.3390/catal11091130 - 20 Sep 2021
Cited by 22 | Viewed by 3105
Abstract
The novel 2D/2D S-scheme heterostructure of BiOCl nanosheets coupled with CaIn2S4 nanosheets (CaIn2S4/BiOCl-SOVs), which contains surface oxygen vacancies (SOVs), has been successfully prepared by high-temperature calcination combined with a solvothermal synthetic strategy. Under visible-light irradiation, the [...] Read more.
The novel 2D/2D S-scheme heterostructure of BiOCl nanosheets coupled with CaIn2S4 nanosheets (CaIn2S4/BiOCl-SOVs), which contains surface oxygen vacancies (SOVs), has been successfully prepared by high-temperature calcination combined with a solvothermal synthetic strategy. Under visible-light irradiation, the apparent rate constant (Kapp/mim−1) for phenol degradation on the 1 wt% CaIn2S4/BiOCl-SOVs photocatalyst is about 32.8 times higher than that of pure BiOCl. The superior performance was attributed to the synergistic effect between the SOVs, CaIn2S4, and BiOCl, which can effectively narrow the bandgap and accelerate the interfacial charge separation of CaIn2S4/BiOCl-SOVs heterojunctions. Subsequently, it significantly promotes the generation of superoxide radicals (O2−), hydroxyl radicals, and h+, which participate in the photodegradation process of phenol. The catalyst still maintained a relatively high activity after repeated tests as a demonstration of its photostability. This work successfully proposed an efficient method to design a new 2D/2D S-scheme heterostructure with SOVs as possible photocatalysts in the field of environmental remediation. Full article
(This article belongs to the Special Issue Photocatalytic Degradation of Organic Wastes in Water)
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18 pages, 7776 KiB  
Article
Au-TiO2 Synthesized by a Microwave- and Sonochemistry-Assisted Sol-Gel Method: Characterization and Application as Photocatalyst
by Rafael Hernández, José Rosendo Hernández-Reséndiz, Marisela Cruz-Ramírez, Rodrigo Velázquez-Castillo, Luis Escobar-Alarcón, Luis Ortiz-Frade and Karen Esquivel
Catalysts 2020, 10(9), 1052; https://doi.org/10.3390/catal10091052 - 13 Sep 2020
Cited by 20 | Viewed by 3528
Abstract
Titanium dioxide (TiO2) is a widely used and well studied photocatalyst synthesized using different methodologies, including sol-gel, which allows one to modify the material in a one-pot step. By using a microwave- and sonochemistry-assisted sol-gel method, x wt.% Au-TiO2 photocatalysts [...] Read more.
Titanium dioxide (TiO2) is a widely used and well studied photocatalyst synthesized using different methodologies, including sol-gel, which allows one to modify the material in a one-pot step. By using a microwave- and sonochemistry-assisted sol-gel method, x wt.% Au-TiO2 photocatalysts were successfully synthesized. Physicochemical characterization of the photocatalysts shows an average crystallite size of 10.5 nm and an even morphological distribution of spherical particles with the sonochemistry synthesis method. For the microwave method an average value of crystallite size of 8.3 nm was found and it presents an increase with the amount of Au load. The cyclic voltammetric response and Mott-Schottky analysis are consistent with a semiconductor material containing metallic particles and for a heterophase junction of anatase and brookite with oxygen vacancies, respectively. The photocatalytic activity was assessed by paracetamol degradation in an aqueous solution as model. The sonochemistry-synthesized photocatalysts display the most promising results as they have a better paracetamol removal and the amount of gold in the catalyst (0.7 wt.%) was found to be optimal for this process. Full article
(This article belongs to the Special Issue Photocatalytic Degradation of Organic Wastes in Water)
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17 pages, 3141 KiB  
Article
Synthesis and Characterization of Zinc Peroxide Nanoparticles for the Photodegradation of Nitrobenzene Assisted by UV-Light
by Jesús Isaías De León Ramírez, Víctor Alfredo Reyes Villegas, Sergio Pérez Sicairos, Esteban Hernández Guevara, Mirna Del Carmen Brito Perea and Bertha Landeros Sánchez
Catalysts 2020, 10(9), 1041; https://doi.org/10.3390/catal10091041 - 10 Sep 2020
Cited by 18 | Viewed by 4155
Abstract
The contamination of both soil and water by nitrobenzene (NB) is a problem that has been studied, where several reactive agents have been developed for the degradation of this compound as well as different methods. Nanoparticles with semiconductive properties have been studied for [...] Read more.
The contamination of both soil and water by nitrobenzene (NB) is a problem that has been studied, where several reactive agents have been developed for the degradation of this compound as well as different methods. Nanoparticles with semiconductive properties have been studied for organic compounds photodegradation due to their assistance in optimizing the degradation processes. Two of the most promising photocatalysts are ZnO and TiO2 because of their optimal results. In the present work the performance of the zinc peroxide (ZnO2) nanoparticles was evaluated. ZnO2 nanoparticles were synthesized from zinc acetate and hydrogen peroxide using the Sol-Gel method under ultrasound assistance. The characterization was carried out by UV–Vis spectroscopy, infrared Fourier transform total reflectance (ATR-FT-IR) spectroscopy, Raman spectroscopy, X-ray diffraction (XRD), Zeta potential, dynamic light scattering (DLS), field emission scanning electron microscopy (FE-SEM), and Energy Dispersive X-ray spectroscopy (EDX). The experiments for the degradation of NB were carried out in a photoreactor with UV lamps of 254 nm at 25 °C, using a solution of nitrobenzene with the nanoparticles. The best conditions for NB photodegradation were 30 ppm (ZnO2) and 15 ppm (NB) at pH 2, reaching up to 90% degradation in 2 h. The intermediates formed during the photodegradation of NB were identified by gas chromatography mass spectrometry. Full article
(This article belongs to the Special Issue Photocatalytic Degradation of Organic Wastes in Water)
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12 pages, 2011 KiB  
Article
The Effect of Electrolytes on the Photodegradation Kinetics of Caffeine
by Pedro M. Rendel and Giora Rytwo
Catalysts 2020, 10(6), 644; https://doi.org/10.3390/catal10060644 - 8 Jun 2020
Cited by 7 | Viewed by 2661
Abstract
Unsuccessfully treated by the existing wastewater-treatment processes, caffeine concentrations in wastewater effluents and natural reservoirs are constantly rising. Photodegradation treatment processes are drawing much attention due to their potential to oxidize and remove such, and similar contaminating compounds from treated waters. In continuation [...] Read more.
Unsuccessfully treated by the existing wastewater-treatment processes, caffeine concentrations in wastewater effluents and natural reservoirs are constantly rising. Photodegradation treatment processes are drawing much attention due to their potential to oxidize and remove such, and similar contaminating compounds from treated waters. In continuation to our previous work on the photodegradation kinetics of caffeine in water by UV/H2O2 and UV/TiO2, this work evaluates the influence of various electrolytes, including NaCl, KCl, MgCl2, NaBr, and KBr, on the kinetics of the UV/H2O2 photodegradation of caffeine, aiming at estimating the efficiency of the method in more complex water systems. Results show that the efficiency of the UV/H2O2 photodegradation reactions is strongly affected by ionic strength and the presence of electrolytes in the solution. While chloride electrolytes were shown to optimize or reduce the process efficiency pending on their concentration. The sole presence of NaBr and KBr shows an immediate reduction in the efficiency of the photodegradation. Empirical apparent-rate-coefficients and curves describing the effect of the different electrolytes on the photodegradation kinetics of caffeine are presented. Full article
(This article belongs to the Special Issue Photocatalytic Degradation of Organic Wastes in Water)
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16 pages, 5528 KiB  
Article
Adsorption and Photocatalytic Study of Phenol Using Composites of Activated Carbon Prepared from Onion Leaves (Allium fistulosum) and Metallic Oxides (ZnO and TiO2)
by Diego Felipe Hernández-Barreto, Jenny Paola Rodriguez-Estupiñán, Juan Carlos Moreno-Piraján, Rocío Sierra Ramírez and Liliana Giraldo
Catalysts 2020, 10(5), 574; https://doi.org/10.3390/catal10050574 - 20 May 2020
Cited by 18 | Viewed by 4164
Abstract
The aim of this study was to evaluate and compare the adsorption and photocatalytic activity of activated carbon-based photocatalysts. Titanium dioxide (TiO2) and zinc oxide (ZnO) were chosen as semiconductors to prepare composites with activated carbon by the wet impregnation method. [...] Read more.
The aim of this study was to evaluate and compare the adsorption and photocatalytic activity of activated carbon-based photocatalysts. Titanium dioxide (TiO2) and zinc oxide (ZnO) were chosen as semiconductors to prepare composites with activated carbon by the wet impregnation method. Activated carbon was prepared using as starting material onion leaves (Allium fistulosum) and as activating agent phosphoric acid (H3PO4). Photooxidation and batch adsorption of phenol was studied to compare the efficiency of the materials prepared. The results showed that the composite AC–TiO2 has a greater photocatalytic activity and a better adsorption capacity compared to AC–ZnO composite. Full article
(This article belongs to the Special Issue Photocatalytic Degradation of Organic Wastes in Water)
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16 pages, 4558 KiB  
Article
Solar Degradation of Sulfamethazine Using rGO/Bi Composite Photocatalysts
by María Fernández-Perales, Marisa Rozalen, Manuel Sánchez-Polo, José Rivera-Utrilla, María Victoria López-Ramón and Miguel A. Álvarez
Catalysts 2020, 10(5), 573; https://doi.org/10.3390/catal10050573 - 20 May 2020
Cited by 16 | Viewed by 2708
Abstract
Heterogeneous photocatalysts for water decontamination were obtained by the optimized synthesis of bismuth-functionalized reduced graphene oxide (rGO/Bi) using the Hummer method and microwave treatment. Sulfamethazine (SMZ) was used as model pollutant to evaluate the photocatalytic efficacy. Photocatalysts were characterized by VP-SEM, HRTEM, XDR, [...] Read more.
Heterogeneous photocatalysts for water decontamination were obtained by the optimized synthesis of bismuth-functionalized reduced graphene oxide (rGO/Bi) using the Hummer method and microwave treatment. Sulfamethazine (SMZ) was used as model pollutant to evaluate the photocatalytic efficacy. Photocatalysts were characterized by VP-SEM, HRTEM, XDR, XPS, RAMAN, and FTIR analyses, which confirmed the effective reduction of GO to rGO and the presence of bismuth as a crystalline phase of Bi2O3 polydispersed on the surface. Their performance was influenced by the rGO/Bi ratio, microwave temperature, and treatment time. The as-obtained 5%rGO/Bi composite had the highest photocatalytic activity for SMZ degradation under visible light irradiation (λ > 400 nm), achieving 100% degradation after only 2 h of treatment. The degradation yield decreased with higher percentages of rGO. Accordingly, the rGO/Bi catalysts efficiently removed SMZ, showing a high photocatalytic activity, and remained unchanged after three treatment cycles; furthermore, cytotoxicity tests demonstrated the nontoxicity of the aqueous medium after SMZ degradation. These findings support the potential value of these novel composites as photocatalysts to selectively remove pollutants in water treatment plants. Full article
(This article belongs to the Special Issue Photocatalytic Degradation of Organic Wastes in Water)
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25 pages, 5658 KiB  
Article
Hydrothermal Synthesis of rGO-TiO2 Composites as High-Performance UV Photocatalysts for Ethylparaben Degradation
by Miller Ruidíaz-Martínez, Miguel A. Álvarez, María Victoria López-Ramón, Guillermo Cruz-Quesada, José Rivera-Utrilla and Manuel Sánchez-Polo
Catalysts 2020, 10(5), 520; https://doi.org/10.3390/catal10050520 - 8 May 2020
Cited by 88 | Viewed by 8017
Abstract
A series of reduced graphene oxide-TiO2 composites (rGO-TiO2) were prepared by hydrothermal treatment using graphite and titanium isopropoxide as raw materials. The structural, surface, electronic, and optical properties of the prepared composites were extensively characterized by N2 adsorption, FTIR, [...] Read more.
A series of reduced graphene oxide-TiO2 composites (rGO-TiO2) were prepared by hydrothermal treatment using graphite and titanium isopropoxide as raw materials. The structural, surface, electronic, and optical properties of the prepared composites were extensively characterized by N2 adsorption, FTIR, XRD, XPS, Raman spectroscopy, and DRS. GO was found to be effectively reduced and TiO2 to be in pure anatase phase in all composites obtained. Finally, experiments were performed to evaluate the effectiveness of these new materials as photocatalysts in the degradation of ethylparaben (EtP) by UV radiation. According to the band-gap energies obtained (ranging between 3.09 eV for 4% rGO-TiO2 to 2.55 eV for 30% rGO-TiO2), the rGO-TiO2 composites behave as semiconductor materials. The photocatalytic activity is highest with a rGO content of 7 wt% (7% rGO-TiO2), being higher than observed for pure TiO2 (Eg = 3.20 eV) and achieving 98.6% EtP degradation after only 40 min of treatment. However, the degradation yield decreases with higher percentages of rGO. Comparison with rGO-P25 composites showed that a better photocatalytic performance in EtP degradation is obtained with synthesized TiO2 (rGO-TiO2), probably due to the presence of the rutile phase (14.1 wt %) in commercial P25. Full article
(This article belongs to the Special Issue Photocatalytic Degradation of Organic Wastes in Water)
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17 pages, 5037 KiB  
Article
Synthesis of Magnetic Fe3O4/ZnWO4 and Fe3O4/ZnWO4/CeVO4 Nanoparticles: The Photocatalytic Effects on Organic Pollutants upon Irradiation with UV-Vis Light
by Mohammad Amin Marsooli, Mehdi Rahimi Nasrabadi, Mahdi Fasihi-Ramandi, Kourosh Adib, Saeid Pourmasoud, Farhad Ahmadi, Mohammad Eghbali, Ali Sobhani Nasab, Monika Tomczykowa and Marta E. Plonska-Brzezinska
Catalysts 2020, 10(5), 494; https://doi.org/10.3390/catal10050494 - 1 May 2020
Cited by 38 | Viewed by 3927
Abstract
Magnetic Fe3O4/ZnWO4 and Fe3O4/ZnWO4/CeVO4 nanoparticles with different molar ratios of CeVO4 to other inorganic components were synthesized through co-precipitation with a sonochemical-assisted method. X-ray diffraction, energy dispersive X-ray spectroscopy, Fourier [...] Read more.
Magnetic Fe3O4/ZnWO4 and Fe3O4/ZnWO4/CeVO4 nanoparticles with different molar ratios of CeVO4 to other inorganic components were synthesized through co-precipitation with a sonochemical-assisted method. X-ray diffraction, energy dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy, ultraviolet-visible diffuse reflectance spectroscopy, vibrating sample magnetometry, and scanning electron microscopy (SEM) methods were used for the physico–chemical characterization of the obtained nanoparticles. As shown in the SEM images, the average sizes of the Fe3O4/ZnWO4 and Fe3O4/ZnWO4/CeVO4 nanoparticles that formed aggregates were approximately 50–70 nm and 80–100 nm, respectively. The photocatalytic performance of these nanoparticles was examined by measuring methylene blue degradation under visible light (assisted by H2O2). The sample with a mass ratio of 1:2:1 (Fe3O4/ZnWO4/CeVO4, S4) exhibited optimal photocatalytic performance, and thus this sample was subsequently used for the photodegradation of different organic pollutants upon irradiation with ultraviolet (UV) and visible light. Approximately 90% and 70% degradation of methyl violet and methylene blue, respectively, was observed after visible light irradiation. Additionally, the mechanism of the photocatalytic reaction was investigated by measuring ˙OH release under UV light in a system with terephthalic acid and by measuring the release of ˙O2−, ˙OH, and hole scavengers. Full article
(This article belongs to the Special Issue Photocatalytic Degradation of Organic Wastes in Water)
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11 pages, 1804 KiB  
Article
Degradation of Meropenem by Heterogeneous Photocatalysis Using TiO2/Fiberglass Substrates
by Alejandro Altamirano Briones, Iván Cóndor Guevara, David Mena, Isabel Espinoza, Christian Sandoval-Pauker, Luis Ramos Guerrero, Paul Vargas Jentzsch and Florinella Muñoz Bisesti
Catalysts 2020, 10(3), 344; https://doi.org/10.3390/catal10030344 - 20 Mar 2020
Cited by 13 | Viewed by 4904
Abstract
Meropenem (MER), a carbapenem, is considered a last-resort antibiotic. Its presence in water bodies, together with other antibiotics, has brought about environmental problems related to the destruction of natural microorganisms and the development of antibiotic-resistant bacteria. Herein, the degradation of MER by heterogeneous [...] Read more.
Meropenem (MER), a carbapenem, is considered a last-resort antibiotic. Its presence in water bodies, together with other antibiotics, has brought about environmental problems related to the destruction of natural microorganisms and the development of antibiotic-resistant bacteria. Herein, the degradation of MER by heterogeneous photocatalysis using TiO2 immobilized on fiberglass substrates is reported. Morphological characterization of the substrates was performed by Scanning Electron Microscopy (SEM). Three pH values (4.0, 5.7, and 7.9) were tested for the treatment of MER solutions (100 mg/L). The best rate constants and MER removals were obtained at pH 4.0 (0.032 min−1; 83.79%) and 5.7 (0.032 min−1; 83.48%). Chemical Oxygen Demand (COD) and Total Organic Carbon (TOC) removals of 25.80% and 29.60% were achieved for the treatment at a pH value of 5.7. The reuse and regeneration of the plates were also tested. The activity of the substrates was maintained until the fourth cycle of reuse, nonetheless, a decrease in MER removal was observed for the 5th cycle. After the fourth cycle of reuse, the activity of the substrates was recovered by a regeneration procedure involving a wash stage of the substrates with a 1% H2O2 solution in an ultrasonic bath. Full article
(This article belongs to the Special Issue Photocatalytic Degradation of Organic Wastes in Water)
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12 pages, 4160 KiB  
Article
Ultrasonication-Assisted Synthesis of ZnxCd1−xS for Enhanced Visible-Light Photocatalytic Activity
by Lei Yang, Maolin Zhang, Mingzhu Liu, You Fan, Haijie Ben, Longfeng Li, Xianliang Fu and Shifu Chen
Catalysts 2020, 10(3), 276; https://doi.org/10.3390/catal10030276 - 1 Mar 2020
Cited by 11 | Viewed by 3054
Abstract
ZnxCd1−xS as a solid solution photocatalyst has attracted widespread attention for its unique adjustable band gap structure and good and stable performance. A novel synthesis approach for ZnxCd1−xS is still required to further improve its [...] Read more.
ZnxCd1−xS as a solid solution photocatalyst has attracted widespread attention for its unique adjustable band gap structure and good and stable performance. A novel synthesis approach for ZnxCd1−xS is still required to further improve its performance. In this study, we synthesized a series of ZnxCd1−xS (x = 0−1) solid solutions via an ultrasonication-assisted hydrothermal route. In comparison with conventional methods of preparation, the sample prepared by our innovative method showed enhanced photocatalytic activity for the degradation of a methyl orange (MO) solution under visible light due to its high crystallinity and small crystallite size. Furthermore, the composition and bandgap of ZnxCd1−xS can be tuned by adjusting the mole ratio of Zn2+/Cd2+. Zn0.3Cd0.7S shows the highest level of activity and stability for the degradation of MO with k = 0.85 h−1, which is 2.2 times higher than that of CdS. The balance between band gap structure-directed redox capacity and light absorption of Zn0.3Cd0.7S accounts for its high photocatalytic performance, both of which are determined by the composition of the solid solution. Also, a degradation mechanism of MO over the sample is tentatively proposed. This study demonstrates a new strategy to synthesize highly efficient sulfide photocatalysts. Full article
(This article belongs to the Special Issue Photocatalytic Degradation of Organic Wastes in Water)
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13 pages, 4285 KiB  
Article
NOM (HA and FA) Reduction in Water Using Nano Titanium Dioxide Photocatalysts (P25 and P90) and Membranes
by Mariola Rajca
Catalysts 2020, 10(2), 249; https://doi.org/10.3390/catal10020249 - 19 Feb 2020
Cited by 7 | Viewed by 2913
Abstract
This study examined the removal of natural organic substances (humic acids-HA, and fulvic acids-FA) from model solutions using photocatalysis and ultrafiltration. The effect of two nano titanium dioxide types (P25 and P90) with different active surface areas and two UV lamps (low-pressure and [...] Read more.
This study examined the removal of natural organic substances (humic acids-HA, and fulvic acids-FA) from model solutions using photocatalysis and ultrafiltration. The effect of two nano titanium dioxide types (P25 and P90) with different active surface areas and two UV lamps (low-pressure and medium-pressure) on the effectiveness of FA and HA removal during photocatalysis was tested. An integrated photocatalytic + ultrafiltration system was also analyzed to determine the effectiveness of FA and HA removal and the changes in the relative permeate flux (Ultrafiltration Membrane Fouling-UF). We observed that photocatalysis using the P90 nano titanium dioxide was more efficient than the P25 due to the larger surface area (2×). The decomposition of organic substances proceeded efficiently up to 30 min of solution exposure, and the use of a medium-pressure lamp accelerated compound decomposition relative to the low-pressure lamp. The applied photocatalysis + ultrafiltration system was characterized by a high degree of FA removal while improved hydraulic efficiency was observed during ultrafiltration. Full article
(This article belongs to the Special Issue Photocatalytic Degradation of Organic Wastes in Water)
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