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Jin J, Liu C, Dai C, Zeng C, Jia Y, Liu X. Boosting the activity for organic pollutants removal of In 2O 3 by loading Ag particles under natural sunlight irradiation. Environ Res 2024; 251:118649. [PMID: 38458589 DOI: 10.1016/j.envres.2024.118649] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2023] [Revised: 02/01/2024] [Accepted: 03/05/2024] [Indexed: 03/10/2024]
Abstract
A novel photocatalyst In2O3 with loading Ag particles is prepared via a facile one-step annealing method in air atmosphere. The Ag/In2O3 exhibits considerable photoactivity for decomposing sulfisoxazole (SOX), tetracycline hydrochloride (TC), and rhodamine B (RhB) under natural sunlight irradiation, which is much higher than that of pristine In2O3 and Ag species. After natural sunlight irradiation for 100 min, 70.6% of SOX, 65.6% of TC, and 81.9% of RhB are degraded over Ag/In2O3, and their corresponding chemical oxygen demand (COD) removal ratio achieve 95.4%, 38.4%, and 93.6%, respectively. A batch of experiments for degrading SOX with adjusting pollutant solution pH and adding coexisting anions over Ag/In2O3 are carried out to estimate its practical application prospect. Particularly, the as-prepared Ag/In2O3 possesses a superior stability, which exhibits no noticeable deactivation in decomposing SOX after eight cycles' reactions. In addition, the Ag/In2O3 coated on a frosted glass plate, also possesses a superior activity and stability for SOX removal, which solve the possible second pollution of residual powdered catalyst in water. Ag particles on In2O3 working as electron accepter improve charge separation and transfer efficiency, as well as the photo-absorption and organic pollutants affinity, leading to the boosted photoactivity of Ag/In2O3. The photocatalytic mechanism for degrading SOX and degradation process over Ag/In2O3 has been systemically investigated and proposed. This work offers an archetype for the rational design of highly efficient photocatalysts by metal loading.
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Affiliation(s)
- Jiahui Jin
- Institute of Advanced Materials, College of Chemistry and Chemical Engineering, Key Lab of Fluorine and Silicon for Energy Materials and Chemistry of Ministry of Education, Jiangxi Normal University, Nanchang, 330022, China
| | - Chengyin Liu
- School of Environmental and Material Engineering, Yantai University, Yantai, 264005, Shandong, China
| | - Chunhui Dai
- Jiangxi Key Laboratory for Mass Spectrometry and Instrumentation, East China University of Technology, Nanchang, 330013, China
| | - Chao Zeng
- Institute of Advanced Materials, College of Chemistry and Chemical Engineering, Key Lab of Fluorine and Silicon for Energy Materials and Chemistry of Ministry of Education, Jiangxi Normal University, Nanchang, 330022, China.
| | - Yushuai Jia
- Institute of Advanced Materials, College of Chemistry and Chemical Engineering, Key Lab of Fluorine and Silicon for Energy Materials and Chemistry of Ministry of Education, Jiangxi Normal University, Nanchang, 330022, China
| | - Xin Liu
- Institute of Advanced Materials, College of Chemistry and Chemical Engineering, Key Lab of Fluorine and Silicon for Energy Materials and Chemistry of Ministry of Education, Jiangxi Normal University, Nanchang, 330022, China.
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2
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Sun M, Ali S, Liu C, Dai C, Liu X, Zeng C. Synergistic effect of Fe doping and oxygen vacancy in AgIO 3 for effectively degrading organic pollutants under natural sunlight. Environ Pollut 2024; 344:123325. [PMID: 38190871 DOI: 10.1016/j.envpol.2024.123325] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2023] [Revised: 01/01/2024] [Accepted: 01/06/2024] [Indexed: 01/10/2024]
Abstract
In this work, a series of hydrogenated Fe-doped AgIO3 (FAI-x) catalysts are synthesized for photodegrading diverse azo dyes and antibiotics. Under the irradiation of natural sunlight with a light intensity of ∼60 mW/cm2, the optimum FAI-10 exhibits a considerable rate constant for decomposing methyl orange (MO) of 0.067 min-1, about 7.4 times higher than that of AgIO3 (0.009 min-1), and 24.6% and 83.8% of MO can be decomposed over AgIO3 and FAI-10 after irradiation for 40 min. In the amplification photodegradation experiments with using 0.5 g catalyst and 400 mL MO dye solution (10 mg/L), FAI-10 possesses greatly higher photoreactivity to common semiconductors (ZnO, TiO2, In2O3 and Bi2MoO6), and the photodegradation rates over FAI-10 are 92%. Particularly, the FAI-10 shows superior stability, the activity of which remains unaltered after 8 continuous cycles. Foreign ions and water bodies have slight effect on the activity of FAI-10, but the MO degradation rates are decreased by adjusting pH values, especially when pH = 11 because of the strong electrostatic repulsion between MO and FAI-10. FAI-10 can also effectively decompose another azo dye (rhodamine B (RhB)) and diverse antibiotics (sulflsoxazole (SOX), chlortetracycline hydrochloride (CTC), tetracycline hydrochloride (TC) and ofloxacin (OFX)). The activity enhancement mechanism of FAI-10 has been systemically investigated and is ascribed to the promoted photo-absorption, charge separation and transfer efficiency, and affinity of organic pollutants, owing to the synergistic effect of Fe doping and oxygen vacancy (Ov). The photocatalytic mechanisms and process for decomposing MO are verified and proposed based on radical trapping experiments and liquid chromatography-mass spectrometry (LC-MS). This work opens an avenue for the fabrication of effective photocatalysts toward water purification.
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Affiliation(s)
- Miaofei Sun
- Institute of Advanced Materials, College of Chemistry and Chemical Engineering, Key Lab of Fluorine and Silicon for Energy Materials and Chemistry of Ministry of Education, Jiangxi Normal University, Nanchang, 330022, China
| | - Sajjad Ali
- Energy, Water, and Environment Lab, College of Humanities and Sciences, Prince Sultan University, Riyadh, 11586, Saudi Arabia
| | - Chengyin Liu
- School of Environmental and Material Engineering, Yantai University, Yantai, 264005, Shandong, China
| | - Chunhui Dai
- Jiangxi Key Laboratory for Mass Spectrometry and Instrumentation, East China University of Technology, Nanchang, 330013, China
| | - Xin Liu
- Institute of Advanced Materials, College of Chemistry and Chemical Engineering, Key Lab of Fluorine and Silicon for Energy Materials and Chemistry of Ministry of Education, Jiangxi Normal University, Nanchang, 330022, China
| | - Chao Zeng
- Institute of Advanced Materials, College of Chemistry and Chemical Engineering, Key Lab of Fluorine and Silicon for Energy Materials and Chemistry of Ministry of Education, Jiangxi Normal University, Nanchang, 330022, China.
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Choi J, Choi W, Hwang H, Tang Y, Jung H. Natural sunlight-driven oxidation of Mn 2+(aq) and heterogeneous formation of Mn oxides on hematite. Chemosphere 2024; 348:140734. [PMID: 37977540 DOI: 10.1016/j.chemosphere.2023.140734] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2023] [Revised: 11/12/2023] [Accepted: 11/13/2023] [Indexed: 11/19/2023]
Abstract
The oxidation of dissolved Mn2+(aq) plays a critical role in driving manganese cycles and regulating the fate of essential elements and contaminants in environmental systems. Based on sluggish oxidation rate, abiotic processes have been considered less effective oxidation pathway for manganese oxidation in environmental systems. Interestingly, a recent study (Jung et al., 2021) has shown that the rapid photochemical oxidation of Mn2+(aq) could be a feasible scenario to uncover the potential significance of abiotic Mn2+(aq) oxidation. Nevertheless, the significance of photochemical oxidation of Mn2+(aq) under natural sunlight exposure remains unclear. Here, we demonstrate the rapid photocatalytic oxidation of Mn2+(aq) and the heterogeneous growth of tunnel-structured Mn oxides under simulated freshwater and seawater conditions in the presence of natural sunlight and hematite. The natural sunlight-driven photocatalytic oxidation of Mn2+(aq) by hematite showed kinetic constants of 1.02 h-1 and 0.342 h-1 under freshwater and seawater conditions, respectively. The natural sunlight-driven photocatalytic oxidation rates are quite comparable to the results obtained from the previous laboratory test using artificial sunlight, which has ∼4.5 times stronger light intensity. It is likely because of ∼5.5 times larger light exposure area in the natural sunlight-driven photocatalytic oxidation than that of the laboratory test using artificial sunlight. We also elucidate the roles of cation species in controlling the oxidation rate of Mn2+(aq) and the crystalline structure of Mn oxide products. Specifically, in the presence of large amounts of cations, the oxidation rate of Mn2+(aq) was slower likely because of competitive adsorption. Furthermore, our findings highlight that Mg2+ contributes significantly to the formation of large-tunneled Mn oxides. These results illuminate the importance of abiotic photocatalytic processes in controlling the redox chemistry of Mn in real environmental aqueous systems on the oxidation of Mn2+(aq), and provide an environmentally sustainable approach to effectively remediate water contaminated with Mn2+(aq) using natural sunlight.
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Affiliation(s)
- Junyeong Choi
- Department of Chemical Engineering, Changwon National University, Changwon, Gyeongsangnam-do, 51140, Republic of Korea
| | - Wooyeol Choi
- Department of Chemical Engineering, Changwon National University, Changwon, Gyeongsangnam-do, 51140, Republic of Korea
| | - Hoyoung Hwang
- Department of Chemical Engineering, Changwon National University, Changwon, Gyeongsangnam-do, 51140, Republic of Korea
| | - Yuanzhi Tang
- School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, GA, 30332, United States.
| | - Haesung Jung
- Department of Chemical Engineering, Changwon National University, Changwon, Gyeongsangnam-do, 51140, Republic of Korea.
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Thongam DD, Chaturvedi H. Heterostructure charge transfer dynamics on self-assembled ZnO on electronically different single-walled carbon nanotubes. Chemosphere 2023; 323:138239. [PMID: 36841447 DOI: 10.1016/j.chemosphere.2023.138239] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/28/2022] [Revised: 01/23/2023] [Accepted: 02/22/2023] [Indexed: 06/18/2023]
Abstract
The charge transfer kinetics of the catalyst particles play a key role in advanced oxidation processes (AOP) for the complete destruction of recalcitrant and persistent contaminants in water. Here, a significant improvement in the photocatalytic performance is observed in the Single-Walled Carbon Nanotube (SWCNT)-ZnO heterostructure photocatalyst. The charge transfer dynamics and factors affecting AOP are studied using ZnO nanoparticles self-assembled onto three electronically different SWCNTs (metallic, semiconducting, and pristine) via the precipitation method, introducing a heterojunction interface. The creation of the SWCNT/ZnO heterostructure interface improves charge transfer and separation, resulting in a charge carrier lifetime of 7.37 ns. Also, surface area, pore size, and pore volumes are increased by 4.2 times compared to those of ZnO. The nanoparticles-coated face-mask fabric used as the floating photocatalyst exhibited high stability and recyclability with 99% RhB degradation efficiency under natural sunlight and 94% under UV light after the 5th cycle. The surface and crystal defects-oxygen or zinc defects/interstitials open new reaction active sites that assist in charge carrier transfer and act as pollutant absorption and interaction sites for enhanced performance. The ideal band edge positions of the valence band and conduction band favor the generation of H2O/OH•, OH·/OH, and O2/HO2• reactive oxygen species. OH• radicals are found to play a vital role in this AOP by using ethanol as an OH• scavenger.
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Affiliation(s)
- Debika Devi Thongam
- School of Energy Science and Engineering, Indian Institute of Technology Guwahati, Assam, 781039, India.
| | - Harsh Chaturvedi
- School of Energy Science and Engineering, Indian Institute of Technology Guwahati, Assam, 781039, India.
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Chen X, Chen J, Li N, Li J, He J, Xu S, Zhu Y, Yao L, Lai Y, Zhu R. Ag 3PO 4-anchored La 2Ti 2O 7 nanorod as a Z-Scheme heterostructure composite with boosted photogenerated carrier separation and enhanced photocatalytic performance under natural sunlight. Environ Pollut 2023; 323:121322. [PMID: 36813103 DOI: 10.1016/j.envpol.2023.121322] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Revised: 02/13/2023] [Accepted: 02/18/2023] [Indexed: 06/18/2023]
Abstract
Developing wide spectra-responsive photocatalysts has attracted considerable attention in the photocatalytic technology to achieve excellent catalytic activity. Ag3PO4, with strong response to light spectra shorter than 530 nm, shows extremely outstanding photocatalytic oxidation ability. Unfortunately, the photocorrosion of Ag3PO4 is still the biggest obstacle to its application. Herein, the La2Ti2O7 nanorod was used to anchor Ag3PO4 nanoparticles in this study, and a novel Z-Scheme La2Ti2O7/Ag3PO4 heterostructure composite was constructed. Remarkably, the composite showed strong responsive to most of the spectra in natural sunlight. The Ag0 formed in-situ acted as the recombination center of photogenerated carriers, which promoted their efficient separation and contributed to the improved photocatalytic performance of the heterostructure. When the mass ratio of Ag3PO4 in the La2Ti2O7/Ag3PO4 catalyst was 50%, the degradation rate constant of Rhodamine B (RhB), methyl orange (MO), chloroquine phosphate (CQ), tetracycline (TC), and phenol under natural sunlight irradiation were 0.5923, 0.4463, 0.1399, 0.0493, and 0.0096 min-1, respectively. Furthermore, the photocorrosion of the composite was greatly inhibited, 76.49% of CQ and 83.96% of RhB were still degraded after four cycles. Besides, the holes and O2•- played a significant role in RhB degradation, and it included multiple mechanisms of deethylation, deamination, decarboxylation, and cleavage of ring-structures. Moreover, the treated solution can also show safety to the water receiving environment. Overall, the synthesized Z-Scheme La2Ti2O7/Ag3PO4 composite exhibited immense potential for removing various organic pollutants through photocatalytic technology under natural sunlight irradiation.
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Affiliation(s)
| | | | - Ning Li
- Foshan University, Foshan 528225, China; Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510610, China
| | - Jiesen Li
- Foshan University, Foshan 528225, China; Department of Research and Development, Guangzhou Ginpie Technology Co., Ltd., Guangzhou 510670, China
| | - Juhua He
- Foshan University, Foshan 528225, China; Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology, Hong Kong 999077, China
| | - Song Xu
- Foshan University, Foshan 528225, China
| | - Yanping Zhu
- College of Natural Resources and Environment, South China Agricultural University, Guangzhou 510642, China
| | - Liang Yao
- Foshan University, Foshan 528225, China
| | - Yiqi Lai
- Foshan University, Foshan 528225, China
| | - Runliang Zhu
- Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China.
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Thongam DD, Chaturvedi H. Induced defect and ZnO nano-flower formation by N, N, dimethylformamide solvent for natural sunlight responsive floating photocatalytic advanced oxidation process. Chemosphere 2023; 313:137600. [PMID: 36549513 DOI: 10.1016/j.chemosphere.2022.137600] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Revised: 11/01/2022] [Accepted: 12/17/2022] [Indexed: 06/17/2023]
Abstract
The increasing disposal of dyes and face-mask propel to hunt for a solution to fight water pollution while assisting sustainability. This research overcomes the key challenges associated with implementing photocatalytic water treatment by using natural sunlight active photocatalyst, changing slurry system, eliminating the use of external triggering sources, and reusing face-mask fabric coated with ZnO to act as a floating photocatalyst. Unique morphological structures-cauliflower, hydrangea, and petals-likes are obtained with the variation in synthesis medium (Diethylene glycol (DEG), N, N-dimethyl formamide (DMF), H2O) and methods (precipitation, solvothermal) which are found to be dependent on the solvent properties. With the use of DMF having a higher dielectric constant and formation of dimethyl amine via hydrolysis, it influences in forming petals and flower-like morphologies, unlike DEG solvent. The ZnO-coated face-mask fabric is used as the floating photocatalyst under natural sunlight observing comparable 91% degradation efficiency in 100 min with that of 99% efficiency in the UV light-illuminated slurry system. The formation of petals-like structures, defects from the liberation of DMF molecules from the ZnO surface by calcination, larger pore sizes and pore volumes provided a synergistic effect on enhancing the degradation efficiency in these cases.
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Affiliation(s)
- Debika Devi Thongam
- School of Energy Science and Engineering, Indian Institute of Technology Guwahati, Assam, 781039, India.
| | - Harsh Chaturvedi
- School of Energy Science and Engineering, Indian Institute of Technology Guwahati, Assam, 781039, India.
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Vishwanathan S, Das S. Glucose-mediated one-pot hydrothermal synthesis of hollow magnesium oxide-zinc oxide (MgO-ZnO) microspheres with enhanced natural sunlight photocatalytic activity. Environ Sci Pollut Res Int 2023; 30:8512-8525. [PMID: 35460004 DOI: 10.1007/s11356-022-20283-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2021] [Accepted: 04/11/2022] [Indexed: 06/14/2023]
Abstract
Glucose -mediated one-pot hydrothermal method has been utilized to synthesize hollow spherical MgO-ZnO (xMgO-(1-x)ZnO, x = 0, 0.2, 0.4, 0.6) microstructures which are highly efficient in high-energy ultraviolet (UV) region of natural sunlight. In this process, glucose formed roundish spheres, and simultaneously metal precursors were coated on that spheres during the hydrothermal reaction. X-ray diffraction analysis (XRD) supports the formation of highly crystalline wurtzite structure of MgO-ZnO for Mg loading less than 20%. Higher concentration of Mg produces wurtzite hexagonal ZnO and cubic MgO in the composites. The widening in band gap energy of synthesized MgO-ZnO microspheres compared to ZnO was analyzed by UV-visible diffuse reflectance spectroscopy (UV-DRS) result. Brunauer-Emmett-Teller (BET) surface area analysis showed that with the increase in Mg loading, the specific surface area increases up to 14.27 times as compared to pristine ZnO. The synthesized catalysts were used as an efficient photocatalyst towards the degradation of rhodamine B (RhB), methylene blue (MB), and phenol under natural solar irradiation. Results illustrated that MB and RhB dye solutions were 100% degraded by 0.6 MgO-ZnO in 100 min and 150 min, respectively, whereas pure ZnO samples showed only 65% and 79% degradation. Also, for phenol solution, 0.6 MgO-ZnO showed enhanced degradation efficiency of 72% in 240 min in comparison with 58% degradation shown by ZnO. Additionally, the MgO-ZnO catalysts were stable and showed excellent degradation efficiency up to four consecutive cycles which open a new direction towards potential industrial applications. Hence, the novelty of the current work is to prepare hollow MgO-ZnO microspheres by a single-step hydrothermal process where separate carbon template preparation is not required and to utilize these hollow microspheres as a highly efficient photocatalyst by harnessing the high-energy UV fraction of natural sunlight.
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Affiliation(s)
- Shalini Vishwanathan
- Department of Chemical Engineering, National Institute of Technology Calicut, Calicut, 673601, India
| | - Susmita Das
- Department of Chemical Engineering, National Institute of Technology Calicut, Calicut, 673601, India.
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Vishwanathan S, Laxmi S, Nandan S, Jayan S, Lijo M, Das S. Effect of experimental parameters on photocatalytic degradation efficiency of TiO 2 nanoparticles synthesized by electrochemical method towards Rhodamine B dye solution under natural sunlight. Environ Sci Pollut Res Int 2023; 30:8448-8463. [PMID: 35122642 DOI: 10.1007/s11356-022-18835-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Accepted: 01/20/2022] [Indexed: 06/14/2023]
Abstract
In this study, ~ 40 nm anatase TiO2 nanoparticles were successfully prepared by a simple electrochemical method by using succinic acid as a non-ammonia-based electrolyte solution and titanium sheets as electrodes. The effect of experimental parameters such as conductivity (2-12 mS/cm), pH of the initial solution (5-9), current applied (0.05-2 A), and reaction time (1-4 h) on catalyst productivity has been investigated. The analysis shows that at an optimum conductivity of 8 mS/cm and pH 7, an increase in applied current and reaction time maximizes the productivity of TiO2 nanoparticles. The obtained catalyst was used for photocatalytic degradation of rhodamine B (RhB) under natural sunlight irradiation. The effect of experimental parameters on photocatalytic degradation has also been studied. The result displayed that degradation efficiency was enhanced by ~ 3 times in the alkaline region compared to the normal pH condition and increased with an increase in catalyst loading and decreased with the initial concentration of RhB dye. Investigation of the photocatalytic mechanism by radical trapping experiments showed that RhB photocatalytic degradation was mainly dominated by hole and superoxide radicals, whereas hydroxyl radical plays a minor role. Moreover, the catalyst reusability analysis revealed good stability and showed excellent degradation up to four consecutive cycles with nearly negligible loss of photocatalytic efficiency. Thus, the present work offers a new opportunity in terms of maximization of productivity as well as sunlight-driven photocatalytic activity of the catalyst for their industrial application.
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Affiliation(s)
- Shalini Vishwanathan
- Department of Chemical Engineering, National Institute of Technology Calicut, Calicut-673601, India
| | - Sree Laxmi
- Department of Chemical Engineering, National Institute of Technology Calicut, Calicut-673601, India
| | - Sukanya Nandan
- Department of Chemical Engineering, National Institute of Technology Calicut, Calicut-673601, India
| | - Shoni Jayan
- Department of Chemical Engineering, National Institute of Technology Calicut, Calicut-673601, India
| | - Meghna Lijo
- Department of Chemical Engineering, National Institute of Technology Calicut, Calicut-673601, India
| | - Susmita Das
- Department of Chemical Engineering, National Institute of Technology Calicut, Calicut-673601, India.
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Palaniappan M, Selvaraj D, Kandasamy S, Kahng YH, Narayanan M, Rajendran R, Rangappan R. Architectural MCM 41 was anchored to the Schiff base Co(II) complex to enhance methylene blue dye degradation and mimic activity. Environ Res 2022; 215:114325. [PMID: 36154860 DOI: 10.1016/j.envres.2022.114325] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2022] [Revised: 08/21/2022] [Accepted: 09/08/2022] [Indexed: 06/16/2023]
Abstract
A sequence of Schiff base Cobalt (II) Mobile Composite Matter 41 heterojunction (SBCo(II)-MCM 41) was prepared by post-synthetic protocols. Various characterization techniques were used to characterize the above samples and MCM 41: Morphology, functional groups, optical properties, crystalline nature, pore diameter, and binding energy by scanning electron microscope (SEM), High-resolution transition electron microscopy (HR-TEM), Fourier transform infrared spectroscopy (FTIR), Ultra Violet-Visible Spectroscopy (UV), X-ray powder diffraction (XRD), Brunauer-Emmett-Teller (BET) and X-ray Photoelectron Spectroscopy (XPS). After the encapsulation of SBCo(II) on the MCM 41, the intensity in the 100-plane in powder x-ray diffraction (XRD) decreased significantly; moreover, the light absorption behavior in UV analysis was improved. The change in the surface area and the decrease in the pore diameter of the sample were also demonstrated by the BET study. The XPS results confirmed the presence of Si, O, C, N, and Co in the SBCo(II)-MCM 41 complex. The photocatalytic performance of MCM 41 and SBCo(II)-MCM 41 materials tested by the degradation of methylene blue dye (MBD) shows that MCM 41 immobilization with SBCo(II)complex is rapidly degraded under natural sunlight irradiation. The optimized 10 mg SBCo(II)-MCM 41 catalyst concentrations showed effective enhancement with the highest efficiency of 98% achieved within 2 h compared to the other two SBCo(II)-MCM 41 concentrations. Moreover, the catalytic efficiency of SBCo(II)-MCM 41 showed a biomimetic reaction without using an oxidant, which exposed it as an effective catalyst for amine to imine conversion; it was useful in the medical field for enzymes with structural assembly.
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Affiliation(s)
- Manikandan Palaniappan
- Department of Chemistry, Bioinorganic Lab, Science Block-1, Periyar University, Salem 636 011, Tamil Nadu, India
| | - David Selvaraj
- Department of Chemistry, Bioinorganic Lab, Science Block-1, Periyar University, Salem 636 011, Tamil Nadu, India; Department of Physics Education, Chonnam National University, Gwangju 500-757, Republic of Korea.
| | - Sabariswaran Kandasamy
- Water-Energy Nexus Laboratory, Department of Environmental Engineering, University of Seoul, Seoul, 02504, Republic of Korea
| | - Yung Ho Kahng
- Department of Physics Education, Chonnam National University, Gwangju 500-757, Republic of Korea.
| | - Mathiyazhagan Narayanan
- Division of Research and Innovations, Department of Biotechnology, Saveetha School of Engineering, Saveetha Institute of Medical and Technical Science, Chennai, 602 105, Tamil Nadu, India
| | | | - Rajavel Rangappan
- Department of Chemistry, Bioinorganic Lab, Science Block-1, Periyar University, Salem 636 011, Tamil Nadu, India.
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Pérez-Lucas G, Martínez-Menchón M, Vela N, Navarro S. Removal assessment of disinfection by-products (DBPs) from drinking water supplies by solar heterogeneous photocatalysis: A case study of trihalomethanes (THMs). J Environ Manage 2022; 321:115936. [PMID: 35981503 DOI: 10.1016/j.jenvman.2022.115936] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Revised: 07/20/2022] [Accepted: 08/01/2022] [Indexed: 06/15/2023]
Abstract
Solar heterogeneous photocatalysis was used to remove trihalomethanes (THMs) from drinking water. THMs, mainly trichloromethane (TCM), tribromomethane (TBM), bromodichloromethane (BDCM) and dibromochloromethane (DBCM) are one of the main class of disinfection by-products (DBPs). THMs were determined by HSGC-MS with detection limits (LODs) ranging from 0.5 μg L-1 to 0.9 μg L-1 for TCM and BDCM, respectively. Results show that a great proportion of THMs present in water are finally transferred to air as a result of their high volatility in the order TCM > BDCM > DBCM > TBM. The use of band-gap semiconductor materials (TiO2 and mainly ZnO) used as photocatalysts in combination with Na2S2O8 as electron acceptor and sulfate radical anion (SO4•-) generator enhanced the photooxidation of all THMs as compared to photolytic test. The time required for 50% of THMs to disappear (DT50) from water calculated for the most effective treatment (ZnO/Na2S2O8) were 12, 42, 57 and 61 min for TCM, TBM, BDCM, and DBCM, respectively. Therefore, solar heterogeneous photocatalysis can be considered as an interesting strategy for THMs removal, especially in sunny areas like Mediterranean basin.
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Affiliation(s)
- Gabriel Pérez-Lucas
- Department of Agricultural Chemistry, Geology and Pedology, Faculty of Chemistry, University of Murcia, Campus Universitario de Espinardo, 30100, Murcia, Spain
| | - Marina Martínez-Menchón
- Department of Agricultural Chemistry, Geology and Pedology, Faculty of Chemistry, University of Murcia, Campus Universitario de Espinardo, 30100, Murcia, Spain
| | - Nuria Vela
- Applied Technology Group to Environmental Health. Faculty of Health Science, Catholic University of Murcia, Campus de Los Jerónimos, s/n. Guadalupe, 30107, Murcia, Spain
| | - Simón Navarro
- Department of Agricultural Chemistry, Geology and Pedology, Faculty of Chemistry, University of Murcia, Campus Universitario de Espinardo, 30100, Murcia, Spain.
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Wang Y, Liu Y, Tian F, Bao S, Sun C, Yang W, Yu Y. MnIn 2S 4 nanosheets growing on rods-like β-MnO 2 via covalent bonds as high-performance photocatalyst for boosting Cr(VI) photocatalytic reduction under visible light irradiation: Behavior and mechanism study. J Colloid Interface Sci 2022; 625:264-77. [PMID: 35717842 DOI: 10.1016/j.jcis.2022.06.015] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2022] [Revised: 05/29/2022] [Accepted: 06/04/2022] [Indexed: 11/21/2022]
Abstract
It is an urgent and onerous task to develop catalysts for photocatalytic reduction of Cr(VI) in wastewater under wide pH range. In this work, a novel hierarchical Z-scheme MnO2/MnIn2S4 (MISO) heterojunction photocatalyst with MnIn2S4 nanosheets growing on the surface of β-MnO2 nanorods is constructed for efficient photocatalytic reduction of Cr(VI). The optimized 2.0-MISO photocatalyst exhibits the almost 100% reduction efficiency in the pH range of 2.1-5.6 under visible light irradiation, and the apparent rate constant is 0.05814 min-1, which is 29.96 and 3.27 times higher than the pure β-MnO2 and MnIn2S4, respectively. A efficient photocatalytic reduction of Cr(VI) to Cr(III) species on 2.0-MISO photocatalyst in actual industry wastewater (286.7 mg/L) up to 99.8% is achieved. Under natural light, the 2.0-MISO photocatalyst also shows rapid reduction of Cr(VI) species. The photocorrosion of MnIn2S4 was significantly hindered by the construction of heterojunction. And the O2- and e- species are the main active species during the Cr(VI) photoreduction process. The connection mode between MnIn2S4 and β-MnO2 is verified by DFT calculations and a possible photocatalytic mechanism is also proposed.
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12
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Aslam M, Qamar MT, Soomro MT, Danish EY, Ismail IMI, Hameed A. The role of size-controlled CeO 2 nanoparticles in enhancing the stability and photocatalytic performance of ZnO in natural sunlight exposure. Chemosphere 2022; 289:133092. [PMID: 34856239 DOI: 10.1016/j.chemosphere.2021.133092] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Revised: 11/22/2021] [Accepted: 11/25/2021] [Indexed: 06/13/2023]
Abstract
In order to enhance the photocatalytic performance and stability, the various proportions of the size controlled cerium oxide (CeO2) nanoparticles were dispersed at the pre-synthesized ZnO. Although, the expected dual absorption onsets, probably due to the diminutive difference between the bandgaps of CeO2 (∼2.9 eV) and ZnO (∼3.1 eV), were not observed however, a blue shift in the bandgap energy of ZnO was witnessed with the increasing surface density of CeO2 particles. The delayed excitons recombination process with the increasing concentration of CeO2 nanoparticles was verified by the PL spectra. The structural investigation by Raman and XRD analysis revealed the surface attachment of CeO2 particles without altering the rock-salt lattice of ZnO. The morphological and fine microstructural analysis established the uniform distribution of evenly sized CeO2 particles at the surface of ZnO with the discrete fringe patterns of both the entities whereas the XPS analysis confirmed the majority of Ce4+ in dispersed CeO2. In comparison to pure ZnO, cyclic voltammetric (CV) analysis, under illumination, exposed the supportive role of surface residing CeO2 particles in eradicating the photo-corrosion of ZnO whereas the chronopotentiometry (CP) predicted the prolonged life-span of the excitons. Compared to pure ZnO, an appreciably high activity was revealed for 10% CeO2 loading as compared to pure ZnO for the removal of mono and di-nitrophenol derivatives and their mixtures under natural sunlight exposure. The variations in the removal rates in the mixture as compared to individual nitrophenol exposed the structure-based priority of ROS for the respective phenol. The significantly enhanced photocatalytic activity of the composite catalysts revealed the incremental role of surface-mounted CeO2 entities in boosting the generation of ROS under sunlight irradiation. The experimental observations were correlated and compiled to establish the mechanism of the removal process.
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Affiliation(s)
- Mohammad Aslam
- Centre of Excellence in Environmental Studies (CEES), King Abdulaziz University, Jeddah, 21589, Saudi Arabia.
| | - Muhammad Tariq Qamar
- Department of Chemistry, Forman Christian College (A Chartered University), Ferozepur Road, Lahore, 54600, Pakistan
| | - Muhammad Tahir Soomro
- Centre of Excellence in Environmental Studies (CEES), King Abdulaziz University, Jeddah, 21589, Saudi Arabia
| | - Ekram Y Danish
- Chemistry Department, Faculty of Science, King Abdulaziz University, P.O. Box 80203, Jeddah, 21589, Saudi Arabia
| | - Iqbal M I Ismail
- Centre of Excellence in Environmental Studies (CEES), King Abdulaziz University, Jeddah, 21589, Saudi Arabia; Chemistry Department, Faculty of Science, King Abdulaziz University, P.O. Box 80203, Jeddah, 21589, Saudi Arabia
| | - Abdul Hameed
- Centre of Excellence in Environmental Studies (CEES), King Abdulaziz University, Jeddah, 21589, Saudi Arabia; National Centre for Physics, Quaid-e-Azam University, Islamabad, 44000, Pakistan.
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13
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Zhang Q, Du R, Tan C, Chen P, Yu G, Deng S. Efficient degradation of typical pharmaceuticals in water using a novel TiO 2/ONLH nano-photocatalyst under natural sunlight. J Hazard Mater 2021; 403:123582. [PMID: 32781276 DOI: 10.1016/j.jhazmat.2020.123582] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Revised: 07/12/2020] [Accepted: 07/23/2020] [Indexed: 06/11/2023]
Abstract
Photocatalytic degradation of typical pharmaceuticals in natural sunlight and in actual water is of great significance. In this study, the oxygen or nitrogen linked heptazine-base polymer (ONLH) was successfully incorporated with TiO2 nanoparticles and formed a TiO2/ONLH nanocomposite which was responded to the natural sunlight. Under natural sunlight, the TiO2/ONLH can effectively degrade ten types of pharmaceuticals. In particular, fluoroquinolone containing N-piperazinyl, and cardiovascular drugs containing long aromatic side chains were easily degraded. The half-life of the best degradation performance of propranolol was less than 5 min. The rate constants of propranolol using the TiO2/ONLH were approximately six- and eight-fold higher than those of pristine TiO2 and ONLH, respectively. Two reactive species (OH and O2-) facilitated the rapid degradation of propranolol, which occurred primarily through the hydroxyl radical addition, ring-opening, and ipso substitution reactions. An acute toxicity test using luminescent bacteria indicated that the toxicity of the propranolol reaction solution gradually decreased with lower total organic carbon (TOC). According to the toxicity evaluation of monomer products, the TiO2/ONLH also reduced the generation of toxic transformation products. The effects of actual water/wastewater have further shown the TiO2/ONLH might be applied for the removal of pharmaceuticals in wastewater.
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Affiliation(s)
- Qianxin Zhang
- School of Environment, State Key Joint Laboratory of Environmental Simulation and Pollution Control (SKLESPC), Beijing Key Laboratory for Emerging Organic Contaminants Control, Tsinghua University, Beijing, 100084, China
| | - Roujia Du
- School of Environment, State Key Joint Laboratory of Environmental Simulation and Pollution Control (SKLESPC), Beijing Key Laboratory for Emerging Organic Contaminants Control, Tsinghua University, Beijing, 100084, China
| | - Cuiwen Tan
- School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou, 510006, China
| | - Ping Chen
- School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou, 510006, China.
| | - Gang Yu
- School of Environment, State Key Joint Laboratory of Environmental Simulation and Pollution Control (SKLESPC), Beijing Key Laboratory for Emerging Organic Contaminants Control, Tsinghua University, Beijing, 100084, China
| | - Shubo Deng
- School of Environment, State Key Joint Laboratory of Environmental Simulation and Pollution Control (SKLESPC), Beijing Key Laboratory for Emerging Organic Contaminants Control, Tsinghua University, Beijing, 100084, China.
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14
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Alenazi DAK, Chandrasekaran S, Soomro MT, Aslam M, Hameed A, Ali S, Danish EY, Ismail IMI. Synthesis, characterization and photocatalytic performance of W 6+ impregnated g-C 3N 4 for the removal of chlorophenol derivatives in natural sunlight exposure. Chemosphere 2021; 265:129135. [PMID: 33302195 DOI: 10.1016/j.chemosphere.2020.129135] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2020] [Revised: 11/15/2020] [Accepted: 11/25/2020] [Indexed: 06/12/2023]
Abstract
The surface of the g-C3N4 was altered by impregnating W6+ ions that transformed to homogeneously coated oxide layer by a calcination process. An enhanced absorption and the suppressed de-excitation in the emission spectra, with the increasing W6+ loading, exposed the supporting role of the coated layer in extending the spectral response as well as the prolonged life span of excitons. The same was further supported by electrochemical impedance spectroscopy (EIS). The XRD and XPS analysis revealed the coated layer as highly crystalline pure phase monoclinic WO3 with the majority of impregnated tungsten ions in 6+ oxidation state respectively, whereas the FESEM and HRTEM analysis substantiated the uniformity of the coated layer with the interlayer spacing of the 0.369 nm. Additionally, the probable formation of individual WO3 nanoparticles or clusters was ruled out. The as-synthesized impregnated photocatalysts, in comparison to pure g-C3N4, were subjected to natural sunlight exposure for the photocatalytic removal of chlorophenol derivatives (2-CP, 3-CP, 4-CP, 2,3-DCP, 2,4-DCP, 2,4,6-TCP and PCP) that revealed the 5 wt% coating as the optimum level for significant removal. The progress of the photocatalytic process was monitored by periodic HPLC analysis whereas ion chromatography (IC) was used for the estimation of released ions. The mineralization capability of the as-synthesized W6+ coated catalysts was measured by the time scale TOC measurements. As the formation of intermediates was indicated in HPLC analysis, selected samples were subjected to GC-MS analysis for the identification of the nature of intermediates. The variable degree of removal of chlorophenol derivatives signified the role of the position and orientation of Cl group. The kinetics of the removal process was evaluated with the calculation of rate constants. The results extracted from the analytical tools and the associated band edge potentials were correlated to speculate the probable mechanism as well as the identification of major reactive oxygen species (ROS) involved in the removal process.
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Affiliation(s)
- Duna A K Alenazi
- Centre of Excellence in Environmental Studies (CEES), King Abdulaziz University, Jeddah, 21589, Saudi Arabia; Chemistry Department, Faculty of Science, King Abdulaziz University, PO Box 80203, Jeddah, 21589, Saudi Arabia; Department of Chemistry, Faculty of Science, Tabuk University, Tabuk, 71491, Saudi Arabia
| | - Sivaraman Chandrasekaran
- Centre of Excellence in Environmental Studies (CEES), King Abdulaziz University, Jeddah, 21589, Saudi Arabia
| | - M Tahir Soomro
- Centre of Excellence in Environmental Studies (CEES), King Abdulaziz University, Jeddah, 21589, Saudi Arabia
| | - M Aslam
- Centre of Excellence in Environmental Studies (CEES), King Abdulaziz University, Jeddah, 21589, Saudi Arabia.
| | - A Hameed
- Centre of Excellence in Environmental Studies (CEES), King Abdulaziz University, Jeddah, 21589, Saudi Arabia; National Centre for Physics, Quaid-e-Azam University, Islamabad, 44000, Pakistan.
| | - Shahid Ali
- Center of Research Excellence in Nanotechnology, King Fahd University of Petroleum & Minerals, Dhahran, 31261, Saudi Arabia
| | - Ekram Y Danish
- Chemistry Department, Faculty of Science, King Abdulaziz University, PO Box 80203, Jeddah, 21589, Saudi Arabia
| | - Iqbal M I Ismail
- Centre of Excellence in Environmental Studies (CEES), King Abdulaziz University, Jeddah, 21589, Saudi Arabia; Chemistry Department, Faculty of Science, King Abdulaziz University, PO Box 80203, Jeddah, 21589, Saudi Arabia
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15
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Wang YK, Ma XY, Zhang S, Tang L, Zhang H, Wang XC. Sunlight-induced changes in naturally stored reclaimed water: Dissolved organic matter, micropollutant, and ecotoxicity. Sci Total Environ 2021; 753:141768. [PMID: 32896733 DOI: 10.1016/j.scitotenv.2020.141768] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2020] [Revised: 08/14/2020] [Accepted: 08/16/2020] [Indexed: 06/11/2023]
Abstract
Natural sunlight is a vital environmental element and plays a significant role in the ecological storage of reclaimed water (RW), but its impacts on RW quality are poorly understood. In this study, sunlight-induced changes in RW with a focus on dissolved organic matter (rDOM) and 52 residual micropollutants were investigated in the field during the summer and winter seasons. The results indicated that sunlight exposure led to the dissipation of chromophoric DOM (CDOM) in the summer (55% loss) and winter (19% loss) after 14 consecutive sunny days. During open storage of RW, CDOM absorption in UVC regions was preferentially removed in the summer, while during the winter there was preferential removal of CDOM in UVA regions. The results also showed higher fluorescent DOM (FDOM) removal in summer than in winter (49% and 28%, respectively). Results in both seasons indicated that humic acid-like compounds were the most photolabile fractions and were preferentially removed under sunlight exposure. Sunlight also induced attenuation of micropollutants in the summer and winter at reductions of 66% and 24% from the initial values, respectively. Significant attenuation (>75%) was only observed for endocrine-disrupting chemicals, pharmaceuticals, and sunscreens in the summer, but they accounted for 76% of the total concentrations. Vibrio fischeri toxicity tests demonstrated that sunlight constantly decreased the luminescent bacteria acute toxicity of RW, which was estimated to be caused mainly by the sunlight-induced changes of FDOM and CDOM, while the detected micropollutants could only explain 0.02%-2% of acute toxicity. These findings have important implications regarding our understanding of the ecological storage of reclaimed water and the contribution of management strategies.
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Affiliation(s)
- Yongkun K Wang
- International Science & Technology Cooperation Center for Urban Alternative Water Resources Development, People's Republic of China; Key Lab of Northwest Water Resource, Environment and Ecology, MOE, People's Republic of China; Engineering Technology Research Center for Wastewater Treatment and Reuse, Shaanxi Province, People's Republic of China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, People's Republic of China
| | - Xiaoyan Y Ma
- International Science & Technology Cooperation Center for Urban Alternative Water Resources Development, People's Republic of China; Key Lab of Northwest Water Resource, Environment and Ecology, MOE, People's Republic of China; Engineering Technology Research Center for Wastewater Treatment and Reuse, Shaanxi Province, People's Republic of China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, People's Republic of China
| | - Shiying Zhang
- International Science & Technology Cooperation Center for Urban Alternative Water Resources Development, People's Republic of China; Key Lab of Northwest Water Resource, Environment and Ecology, MOE, People's Republic of China; Engineering Technology Research Center for Wastewater Treatment and Reuse, Shaanxi Province, People's Republic of China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, People's Republic of China
| | - Lei Tang
- International Science & Technology Cooperation Center for Urban Alternative Water Resources Development, People's Republic of China; Key Lab of Northwest Water Resource, Environment and Ecology, MOE, People's Republic of China; Engineering Technology Research Center for Wastewater Treatment and Reuse, Shaanxi Province, People's Republic of China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, People's Republic of China
| | - Hengfeng Zhang
- International Science & Technology Cooperation Center for Urban Alternative Water Resources Development, People's Republic of China; Key Lab of Northwest Water Resource, Environment and Ecology, MOE, People's Republic of China; Engineering Technology Research Center for Wastewater Treatment and Reuse, Shaanxi Province, People's Republic of China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, People's Republic of China
| | - Xiaochang C Wang
- International Science & Technology Cooperation Center for Urban Alternative Water Resources Development, People's Republic of China; Key Lab of Northwest Water Resource, Environment and Ecology, MOE, People's Republic of China; Engineering Technology Research Center for Wastewater Treatment and Reuse, Shaanxi Province, People's Republic of China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, People's Republic of China.
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16
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Li B, Yuan D, Ma L, Shi C, Li Y. Efficient combustion of chlorinated volatile organic compounds driven by natural sunlight. Sci Total Environ 2020; 749:141595. [PMID: 32836128 DOI: 10.1016/j.scitotenv.2020.141595] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Revised: 07/19/2020] [Accepted: 08/08/2020] [Indexed: 06/11/2023]
Abstract
Catalytic combustion of chlorinated volatile organic compounds (CVOCs) driven by natural sunlight is the promising CVOCs elimination method, which has not been realized. In this work, we designed a new sunlight-driven catalytic system for CVOCs combustion based on a scalable CuMnCeOx gel and a new photothermal conversion device. The CVOCs elimination rate of CuMnCeOx gel was reached to 99% at 250 °C, 25 times higher than that of CuMnCeOx in bulk form. Further, the new photothermal conversion device could heat the CuMnCeOx gel to 300 °C under one standard solar irradiation and this joint showed a stable one standard sunlight-driven CVOCs combustion at the rate of 6.8 mmol g-1 h-1, which was more than 7.8 times higher than the state of the art of photocatalytic CVOCs decomposition. Moreover, the new sunlight-driven thermal catalytic system was able to stable full oxidize the CVOCs in the concentration from 0.1 to 1000 ppm. Therefore, the natural sunlight-driven thermal CVOCs combustion system with high activity and zero secondary pollution shows the potential for large-scale industrial applications.
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Affiliation(s)
- Bo Li
- Hebei Key Lab of Optic-electronic Information and Materials, The College of Physics Science and Technology, Institute of Life Science and Green Development, Hebei University, Baoding, 071002, China
| | - Dachao Yuan
- College of Mechanical and Electrical Engineering, Hebei Agricultural University, Baoding 071001, China
| | - Luping Ma
- College of Mechanical and Electrical Engineering, Hebei Agricultural University, Baoding 071001, China
| | - Chengcheng Shi
- Hebei Key Lab of Optic-electronic Information and Materials, The College of Physics Science and Technology, Institute of Life Science and Green Development, Hebei University, Baoding, 071002, China
| | - Yaguang Li
- Hebei Key Lab of Optic-electronic Information and Materials, The College of Physics Science and Technology, Institute of Life Science and Green Development, Hebei University, Baoding, 071002, China.
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17
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Alhogbi BG, Aslam M, Hameed A, Qamar MT. The efficacy of Co 3O 4 loaded WO 3 sheets for the enhanced photocatalytic removal of 2,4,6-trichlorophenol in natural sunlight exposure. J Hazard Mater 2020; 397:122835. [PMID: 32446141 DOI: 10.1016/j.jhazmat.2020.122835] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/11/2020] [Revised: 04/04/2020] [Accepted: 04/23/2020] [Indexed: 06/11/2023]
Abstract
Owing to the promising photocatalytic performance, the sheet-like WO3 was modified by depositing nanostructured Co3O4 at the surface. The appearance of the varying dual absorption edges in the optical analysis exposed the composite nature of the synthesized materials. The structural analysis revealed the deposition of Co3O4 particles at the surface without altering the lattice of WO3 however, during the processing the cracking of disc was also evidenced. The FESEM and HRTEM analysis corroborated the uniform surface dispersion of Co3O4 nanoparticles. The co-existence of 2+ and 3+ oxidation states of Co in the deposited Co3O4 was examined by XPS analysis. The efficient trapping of excitons by Co3O4 surface entities was witnessed in the emission measurements whereas the same was authenticated by the photo-electrochemical chronopotentiometry. The Co3O4 loaded sheets exhibited substantially enhanced activity for the removal of 2,4,6-trichlorophenol as compared to pure WO3 in the complete spectrum and visible region of natural sunlight exposure. The progress of the degradation process was monitored by HPLC whereas the degradation products were identified by GC-MS. The measurement and identification of the ion released during the photocatalytic process facilitated the estimation of the probable route and role of reactive oxygen species involved in the removal process. Although, the careful analysis of the findings from the analytical tools revealed the major involvement of hydroxyl radicals however, the role of superoxide anions was also exposed. An alternative mechanism of the generation of the superoxide radical involving the 2+ and 3+ oxidation states of Co was also proposed. The effect of the pH and the added concentration of H2O2 on the ease of removal process was also investigated.
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Affiliation(s)
- Basma G Alhogbi
- Chemistry Department, Faculty of Science, King Abdulaziz University, P.O. Box 80203, Jeddah 21589, Saudi Arabia
| | - M Aslam
- Center of Excellence in Environmental Studies (CEES), King Abdulaziz University, Jeddah 21589, Saudi Arabia.
| | - A Hameed
- National Centre for Physics, Quaid-e-Azam University, Islamabad 44000, Pakistan.
| | - M Tariq Qamar
- Department of Chemistry, Forman Christian College (A Chartered University), Ferozepur Road, Lahore 54600, Pakistan
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18
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Aghajari N, Ghasemi Z, Younesi H, Bahramifar N. Synthesis, characterization and photocatalytic application of Ag-doped Fe-ZSM-5@TiO 2 nanocomposite for degradation of reactive red 195 (RR 195) in aqueous environment under sunlight irradiation. J Environ Health Sci Eng 2019; 17:219-232. [PMID: 31321045 PMCID: PMC6582101 DOI: 10.1007/s40201-019-00342-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2018] [Accepted: 01/21/2019] [Indexed: 05/25/2023]
Abstract
BACKGROUND Most dyes have aromatic rings in their structures, which make them highly toxic for human being and aquatic life. Heterogeneous photodegradation using TiO2 nanoparticles is one of the most applied methods used for dye removal. The wide band gap of TiO2 nanoparticles disables its use of the visible light and thus the vast potential of sunlight. To overcome this deficiency, Ag doped TiO2 nanoparticles were loaded on Fe-ZSM-5. METHODS Fe-ZSM-5@TiO2-Ag photocatalyst was synthesized through sol-gel and hydrothermal methods to remove hazardous Reactive Red 195 (RR 195) from aqueous solution. RESULTS Pure phase of Fe-ZSM-5@TiO2-Ag with specific surface area of 332 m2/g was successfully synthesized. Formation of Ti-O-Ag functional group in the photocatalyst structure confirmed the nanocomposite form of the product. SEM and TEM images portrayed the synthesized zeolite and photocatalyst NPs in a size range of ≤100 nm with homogenous distribution of Ag doped TiO2 on Fe-ZSM-5 surface. The band-gap energy of Fe-ZSM-5@TiO2-Ag was calculated 1.97 eV at λ = 630 nm. Photocatalytic activity of the photocatalyst under natural sunlight was investigated through photodecomposition of RR 195 in an aqueous solution. The dye photodecomposition of about 98% was achieved at photocatalyst concentration of 400 mg/L, pH of 3, and dye concentration of 50 mg/L at ambient temperature after 120 min under sunlight using 0.5 ml of TiO2 and silver ammonium nitrate. The photocatalyst reusability was found significant after 5 frequent cycles. CONCLUSION The novel Ag-doped TiO2-Fe-ZSM-5 nanocomposite with sunlight sensitivity can be a promising candidate to purify wastewater containing organic pollutants.
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Affiliation(s)
- Nasrin Aghajari
- Department of Environmental Science, Faculty of Natural Resources, Tarbiat Modares University, Noor, Iran
| | - Zahra Ghasemi
- Department of Fisheries, Faculty of Marine Science and Technology, University of Hormozgan, Bandar Abbas, Postal Code: 7916193145 Iran
| | - Habibollah Younesi
- Department of Environmental Science, Faculty of Natural Resources, Tarbiat Modares University, Noor, Iran
| | - Nader Bahramifar
- Department of Environmental Science, Faculty of Natural Resources, Tarbiat Modares University, Noor, Iran
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19
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Wang JC, Lou HH, Xu ZH, Cui CX, Li ZJ, Jiang K, Zhang YP, Qu LB, Shi W. Natural sunlight driven highly efficient photocatalysis for simultaneous degradation of rhodamine B and methyl orange using I/C codoped TiO 2 photocatalyst. J Hazard Mater 2018; 360:356-363. [PMID: 30130694 DOI: 10.1016/j.jhazmat.2018.08.008] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2018] [Revised: 07/20/2018] [Accepted: 08/04/2018] [Indexed: 05/25/2023]
Abstract
Increasing the efficiency of dye degradation is a critical issue for the application for photocatalysis. It is one of the greatest challenges to enhance the utilization of photo generated carriers in semiconductor, especially for sunlight irradiation. In this study, I/C-codoped TiO2 was synthesized by a simple solvothermal-calcination method. The codoping interstitial carbon and substitutional iodine not only widened the light absorption range of the TiO2 photocatalysts, but also enhanced the separation of photo-induced carriers. The photocatalytic activities of RhB and MO degradation over the 4-I/C-TiO2 photocatalyst could reach 98.2% and 94.2% after 25 min visible light irradiation (λ ≥ 400 nm), respectively. Notably, 4-I/C-TiO2 showed good activity for MO and RhB mixed degradation and could also accomplish the photocatalytic degradation in the above mixed system under natural sunlight irradiation. According to the dark catalytic experiment, I/C-codoping could effectively accelerate the formation of hydroxyl radicals from the generated H2O2, which was formed for the enhanced photocatalytic activity of dye degradation. The gained knowledge may provide some insights into the photocatalytic degradation over the codoped TiO2 catalyst.
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Affiliation(s)
- Ji-Chao Wang
- College of Chemistry and Chemical Engineering, Henan Institute of Science and Technology, Xinxiang, 453000, China; Post-doctoral Station of Environmental Science and Engineering, Henan Normal University, Xinxiang 453000, China.
| | - Hui-Hui Lou
- College of Chemistry and Chemical Engineering, Henan Institute of Science and Technology, Xinxiang, 453000, China
| | - Zhi-Hua Xu
- College of Chemistry and Chemical Engineering, Henan Institute of Science and Technology, Xinxiang, 453000, China
| | - Cheng-Xing Cui
- College of Chemistry and Chemical Engineering, Henan Institute of Science and Technology, Xinxiang, 453000, China
| | - Zhong-Jun Li
- College of Chemistry and Molecular Engineering, Zhengzhou University, Zhengzhou 450000, China
| | - Kai Jiang
- Post-doctoral Station of Environmental Science and Engineering, Henan Normal University, Xinxiang 453000, China
| | - Yu-Ping Zhang
- College of Chemistry and Chemical Engineering, Henan Institute of Science and Technology, Xinxiang, 453000, China.
| | - Ling-Bo Qu
- College of Chemistry and Molecular Engineering, Zhengzhou University, Zhengzhou 450000, China
| | - Weina Shi
- College of Chemistry and Chemical Engineering, Xinxiang University, Xinxiang 453003, China.
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20
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He Q, Chen L, Zhang S, Chen R, Wang H, Zhang W, Song J. Natural sunlight induced rapid formation of water-born algal-bacterial granules in an aerobic bacterial granular photo-sequencing batch reactor. J Hazard Mater 2018; 359:222-230. [PMID: 30036752 DOI: 10.1016/j.jhazmat.2018.07.051] [Citation(s) in RCA: 59] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2018] [Revised: 06/25/2018] [Accepted: 07/11/2018] [Indexed: 06/08/2023]
Abstract
Wastewater treatment by means of algal-bacterial granules has become a hot topic worldwide recently. Rapid granulation of algal-bacterial granules was achieved in an aerobic bacterial granular sequencing batch reactor (SBR) under natural sunlight exposure. Occurrence of abundant filamentous bacteria bridging the water-born algae, and overproduction of extracellular polymeric substances (EPS) (especially polysaccharides (PS), tryptophan & protein-like, and humic acid-like substances) were observed on the first 3 days, while the algae grew into the inner side of the granules and mature granules were obtained on day 7. The growth of the water-born algae slightly decreased the settleability, mean sizes of the granules, but stimulated the bioactivity significantly. Whereas, the biomass retention decreased before day 3, and got stable soon with the maturation period with symbiotic growth of algal-bacterial biomass. Illumina results revealed that the introduction of algae reduced the richness and diversity of bacterial community. Besides, few changes in structure and some compositions shifts in bacterial communities were found, while the predominant algae shifted from Diatomea to green algae Chlorophyceae. The possible mechanism for natural sunlight induced granulation of algal-bacterial granules was thus proposed based on the interactions between algae and bacteria.
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Affiliation(s)
- Qiulai He
- School of Civil Engineering, Wuhan University, Wuhan, China
| | - Li Chen
- School of Civil Engineering, Wuhan University, Wuhan, China
| | - Shujia Zhang
- School of Civil Engineering, Wuhan University, Wuhan, China
| | - Rongfan Chen
- School of Civil Engineering, Wuhan University, Wuhan, China
| | - Hongyu Wang
- School of Civil Engineering, Wuhan University, Wuhan, China.
| | - Wei Zhang
- School of Civil Engineering, Wuhan University, Wuhan, China
| | - Jianyang Song
- School of Civil Engineering, Wuhan University, Wuhan, China
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21
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Hak CH, Sim LC, Leong KH, Lim PF, Chin YH, Saravanan P. M/g-C 3N 4 (M=Ag, Au, and Pd) composite: synthesis via sunlight photodeposition and application towards the degradation of bisphenol A. Environ Sci Pollut Res Int 2018; 25:25401-25412. [PMID: 29951757 DOI: 10.1007/s11356-018-2632-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Accepted: 06/20/2018] [Indexed: 06/08/2023]
Abstract
In this work, natural sunlight successfully induced the deposition of gold (Au), silver (Ag), and palladium (Pd) nanoparticles (NPs) with 17.10, 9.07, and 12.70 wt% onto the surface of graphitic carbon nitride (g-C3N4). The photocatalytic evaluation was carried out by adopting Bisphenol A (BPA) as a pollutant under natural sunlight irradiation. The presence of noble metals was confirmed by EDX, HRTEM, and XPS analysis. The deposition of Ag NPs (7.9 nm) resulted in the degradation rate which was 2.15-fold higher than pure g-C3N4 due to its relatively small particle size, contributing to superior charge separation efficiency. Au/g-C3N4 unveiled inferior photoactivity because the LSPR phenomenon provided two pathways for electron transfer between Au NPs and g-C3N4 further diminished the performance. The improved degradation lies crucially on the particle size and Schottky barrier formation at the interface of M/g-C3N4 (M=Au, Ag, and Pd) but not the visible light harvesting properties. The mechanism insight revealed the holes (h+) and superoxide radical (•O2-) radical actively involved in photocatalytic reaction for all composites.
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Affiliation(s)
- Chen Hong Hak
- Department of Environmental Engineering, Faculty of Engineering and Green Technology, Universiti Tunku Abdul Rahman, Kampar, Perak, Malaysia
| | - Lan Ching Sim
- Department of Environmental Engineering, Faculty of Engineering and Green Technology, Universiti Tunku Abdul Rahman, Kampar, Perak, Malaysia.
- Department of Chemical Engineering, Lee Kong Chian Faculty of Engineering and Science, Universiti Tunku Abdul Rahman, Jalan Sungai Long 9, Bandar Sungai Long, 43000, Kajang, Selangor, Malaysia.
| | - Kah Hon Leong
- Department of Environmental Engineering, Faculty of Engineering and Green Technology, Universiti Tunku Abdul Rahman, Kampar, Perak, Malaysia
| | - Ping Feng Lim
- Department of Environmental Engineering, Faculty of Engineering and Green Technology, Universiti Tunku Abdul Rahman, Kampar, Perak, Malaysia
| | - Yik Heng Chin
- Department of Environmental Engineering, Faculty of Engineering and Green Technology, Universiti Tunku Abdul Rahman, Kampar, Perak, Malaysia
| | - Pichiah Saravanan
- Department of Environmental Science and Engineering, Indian Institute of Technology(ISM), Dhanbad, Dhanbad, Jharkhand, 826004, India
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22
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Wang J, Jin J, Wang X, Yang S, Zhao Y, Wu Y, Dong S, Sun J, Sun J. Facile fabrication of novel BiVO 4/Bi 2S 3/MoS 2 n-p heterojunction with enhanced photocatalytic activities towards pollutant degradation under natural sunlight. J Colloid Interface Sci 2017. [PMID: 28672260 DOI: 10.1016/j.jcis.2017.06.085.] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/30/2022]
Abstract
The novel three-component BiVO4/Bi2S3/MoS2 heterojunction was successfully fabricated through a facile in-situ hydrothermal method based on the formation of the intermediate Bi2S3 by coupling BiVO4 and MoS2 precursor. The Bi2S3 was easily formed attributing to the strong interaction between Bi3+and S2- ions with the aid of the hydrothermal reaction. The photocatalytic performances of samples were systematically investigated via the photocatalytic degradation of Rhodamine B (RhB), methylene blue (MB) and malachite green (MG) under solar light irradiation. As a result, the photocatalytic degradation rate of BM-10 for RhB, MB and MG are 97%, 93% and 94%, respectively. The enhanced photocatalytic activities could be due to the suppression of charge recombination and the enhanced the visible light absorption of BiVO4/Bi2S3/MoS2 heterojunction.
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Affiliation(s)
- Jingzhen Wang
- School of Environment, Henan Normal University, Key Laboratory for Yellow River and Huai River Water Environmental and Pollution Control, Ministry of Education, Henan Key Laboratory for Environmental Pollution Control, Xinxiang, Henan 453007, PR China
| | - Jia Jin
- School of Environment, Henan Normal University, Key Laboratory for Yellow River and Huai River Water Environmental and Pollution Control, Ministry of Education, Henan Key Laboratory for Environmental Pollution Control, Xinxiang, Henan 453007, PR China
| | - Xiangguo Wang
- Soochow Institute for Energy and Materials InnovationS, Soochow University, Suzhou, Jiangsu 215006, PR China
| | - Shengnan Yang
- School of Environment, Henan Normal University, Key Laboratory for Yellow River and Huai River Water Environmental and Pollution Control, Ministry of Education, Henan Key Laboratory for Environmental Pollution Control, Xinxiang, Henan 453007, PR China
| | - Yinlan Zhao
- School of Environment, Henan Normal University, Key Laboratory for Yellow River and Huai River Water Environmental and Pollution Control, Ministry of Education, Henan Key Laboratory for Environmental Pollution Control, Xinxiang, Henan 453007, PR China
| | - Yawen Wu
- School of Environment, Henan Normal University, Key Laboratory for Yellow River and Huai River Water Environmental and Pollution Control, Ministry of Education, Henan Key Laboratory for Environmental Pollution Control, Xinxiang, Henan 453007, PR China
| | - Shuying Dong
- School of Environment, Henan Normal University, Key Laboratory for Yellow River and Huai River Water Environmental and Pollution Control, Ministry of Education, Henan Key Laboratory for Environmental Pollution Control, Xinxiang, Henan 453007, PR China.
| | - Jingyu Sun
- Soochow Institute for Energy and Materials InnovationS, Soochow University, Suzhou, Jiangsu 215006, PR China.
| | - Jianhui Sun
- School of Environment, Henan Normal University, Key Laboratory for Yellow River and Huai River Water Environmental and Pollution Control, Ministry of Education, Henan Key Laboratory for Environmental Pollution Control, Xinxiang, Henan 453007, PR China.
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23
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Gan Z, Sun H, Wang R, Hu H, Zhang P, Ren X. Transformation of acesulfame in water under natural sunlight: joint effect of photolysis and biodegradation. Water Res 2014; 64:113-122. [PMID: 25046375 DOI: 10.1016/j.watres.2014.07.002] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2014] [Revised: 06/30/2014] [Accepted: 07/01/2014] [Indexed: 06/03/2023]
Abstract
The transformation of acesulfame in water under environmentally relevant conditions, including direct and indirect photolysis, biodegradation, and hydrolysis, was systematically evaluated. Under natural sunlight, both direct and indirect photolysis of acesulfame were negligible in sterilized systems at neutral or alkaline pH, whereas direct photolysis occurred at pH of 4 with a rate constant of 0.0355 d(-1) in deionized water. No significant reduction in acesulfame contents was found in the dark controls or in the incubation experiments, indicating acesulfame was resistant to hydrolysis and biodegradation. In unsterilized systems, photolysis was substantially enhanced, implying that there was a joint effect of photolysis and biodegradation or that the sterilization process had the secondary effect of inactivating some photosensitizers. The near-surface summer half-life of acesulfame in the water from the Haihe River was 9 d. Specific experiments revealed the involvement of (1)O2/(3)DOM* in acesulfame photolysis, whereas OH exhibited only a slight contribution in the presence of DOM or bicarbonate. As indicated by the total organic carbon data, no significant mineralization occurred in both sterilized and unsterilized systems after acesulfame was irradiated under simulated sunlight for 7 d, suggesting the generation of persistent intermediates. Finally, major degradation intermediates were analyzed, and the degradation pathways of acesulfame under environmentally relevant conditions were proposed for the first time.
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Affiliation(s)
- Zhiwei Gan
- MOE Key Laboratory of Pollution Processes and Environmental Criteria, College of Environmental Science and Engineering, Nankai University, Tianjin 300071, China
| | - Hongwen Sun
- MOE Key Laboratory of Pollution Processes and Environmental Criteria, College of Environmental Science and Engineering, Nankai University, Tianjin 300071, China.
| | - Ruonan Wang
- MOE Key Laboratory of Pollution Processes and Environmental Criteria, College of Environmental Science and Engineering, Nankai University, Tianjin 300071, China
| | - Hongwei Hu
- MOE Key Laboratory of Pollution Processes and Environmental Criteria, College of Environmental Science and Engineering, Nankai University, Tianjin 300071, China
| | - Pengfei Zhang
- MOE Key Laboratory of Pollution Processes and Environmental Criteria, College of Environmental Science and Engineering, Nankai University, Tianjin 300071, China
| | - Xinhao Ren
- MOE Key Laboratory of Pollution Processes and Environmental Criteria, College of Environmental Science and Engineering, Nankai University, Tianjin 300071, China
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24
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Kühn J, Schutkowski A, Kluge H, Hirche F, Stangl GI. Free-range farming: a natural alternative to produce vitamin D-enriched eggs. Nutrition 2013; 30:481-4. [PMID: 24607306 DOI: 10.1016/j.nut.2013.10.002] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2013] [Revised: 09/25/2013] [Accepted: 10/08/2013] [Indexed: 11/18/2022]
Abstract
OBJECTIVE Food-based strategies need to be developed to improve the vitamin D status of individuals. Recent studies identified ultraviolet B irradiation as an efficient method to enrich mushrooms and eggs with vitamin D. The aim of this study was to determine whether free-range farming of hens could provide a valuable method to produce vitamin D-enriched eggs. METHODS Laying hens were randomly assigned to three groups of 33 to 34 animals each, and were kept either indoors (indoor group), outdoors (outdoor group), or with an indoor/outdoor option (indoor/outdoor group) over 4 wk. RESULTS The study shows that the vitamin D3 content of egg yolk was three- to fourfold higher in the groups that were exposed to sunlight (outdoor and indoor/outdoor groups) compared with the indoor group (P < 0.001). Egg yolk from the outdoor group revealed the highest vitamin D3 content, which averaged 14.3 μg/100 g dry matter (DM), followed by that from the indoor/outdoor group (11.3 μg/100 g DM). Yolk from indoor eggs contained only 3.8 μg vitamin D/100 g DM. The 25-hydroxyvitamin D (25[OH]D3) content of egg yolk was also influenced by sunlight exposure, although less pronounced than the vitamin D content (P < 0.05). In contrast, free-range eggs randomly acquired from supermarkets had relatively low vitamin D contents. CONCLUSION Free-range farming offers an efficient alternative to fortify eggs with vitamin D, provided that farming conditions are sufficiently attractive for hens to range outside.
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Affiliation(s)
- Julia Kühn
- Institute of Agricultural and Nutritional Sciences, Martin-Luther-University Halle-Wittenberg, Halle (Saale), Germany
| | - Alexandra Schutkowski
- Institute of Agricultural and Nutritional Sciences, Martin-Luther-University Halle-Wittenberg, Halle (Saale), Germany
| | - Holger Kluge
- Institute of Agricultural and Nutritional Sciences, Martin-Luther-University Halle-Wittenberg, Halle (Saale), Germany
| | - Frank Hirche
- Institute of Agricultural and Nutritional Sciences, Martin-Luther-University Halle-Wittenberg, Halle (Saale), Germany
| | - Gabriele I Stangl
- Institute of Agricultural and Nutritional Sciences, Martin-Luther-University Halle-Wittenberg, Halle (Saale), Germany.
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