| 1. |
- Metsämuuronen, Sari, et al.
(författare)
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Natural organic matter removal from drinking water by membrane technology
- 2014
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Ingår i: Separation and Purification Reviews. - : Informa UK Limited. - 1542-2119 .- 1542-2127. ; 43:1, s. 1-61
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Tidskriftsartikel (refereegranskat)abstract
- Aquatic natural organic matter (NOM) is a heterogeneous mixture of biopolymers and their degradation products that cause harmful by-products during drinking water production. The great variability in NOM composition makes it difficult to completely remove from drinking water by any single technique. The current paper reviews the NOM removal by micro-, ultra- and nanofiltration and by hybrid processes combining membrane techniques with other unit processes: coagulation, adsorption, and oxidation, and by membrane bioreactors.
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| 2. |
- Al-Hamdi, Abdullah M, et al.
(författare)
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Photocatalytic degradation of phenol by iodine doped tin oxide nanoparticles under UV and sunlight irradiation
- 2015
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Ingår i: Journal of Alloys and Compounds. - : Elsevier. - 0925-8388. ; 618, s. 366-371
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Tidskriftsartikel (refereegranskat)abstract
- Iodine doped tin oxide (SnO2:I) nanoparticles were prepared by sol-gel synthesis and their photocatalytic activities with phenol as a test contaminant were studied. In the presence of the catalysts, phenol degradation under direct sunlight was comparable to what was achieved under laboratory conditions. Photocatalytic oxidation reactions were studied by varying the catalyst loading, light intensity, illumination time, pH of the reactant and phenol concentration. Upon UV irradiation in the presence of SnO2:I nanoparticles, phenol degrades very rapidly within 30 min, forming carboxylic acid which turns the solution acidic. Phenol degradation rate with 1% iodine doped SnO2 nanoparticles is at least an order of magnitude higher compared to the degradation achieved through undoped SnO2 nanoparticles under similar illumination conditions.
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| 3. |
- Ambashta, Ritu D., et al.
(författare)
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Supported iron-based catalysts under influence of static magnetic field for the removal of TBP and EDTA
- 2015
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Ingår i: Desalination and Water Treatment. - : Informa UK Limited. - 1944-3994 .- 1944-3986. ; 54:10, s. 2700-2709
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Tidskriftsartikel (refereegranskat)abstract
- Zerovalent metals offer decontamination of organic toxins in aqueous medium. In the present study, alumina-based iron and iron-nickel in the presence and the absence of magnetic field for the decontamination of tributyl phosphate (TBP) and ethylene diamine tetraacetic acid (EDTA) has been compared. TBP decontamination was improved in the presence of zerovalent metals. EDTA decontamination was not enhanced in the presence of zerovalent metals. The decontamination of TBP using iron-based alumina was higher than iron-nickel. The surface interaction on alumina surface, as characterized by attentuated total reflectance-Fourier transform infrared spectroscopy, and the surface interaction on metallic elements, as characterized by evaluating the magnetic moment values helped to understand the reason for the difference in role of alumina-based iron and iron-nickel on decontamination of TBP and EDTA.
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| 4. |
- Bhatnagar, Amit, et al.
(författare)
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A review of emerging adsorbents for nitrate removal from water
- 2011
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Ingår i: Chemical Engineering Journal. - : Elsevier. - 1385-8947 .- 1873-3212. ; 168:2, s. 493-504
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Tidskriftsartikel (refereegranskat)abstract
- Nitrate, due to its high water solubility, is possibly the most widespread groundwater contaminant in the world, imposing a serious threat to human health and contributing to eutrophication. Among several treatment technologies applied for nitrate removal, adsorption has been explored widely and offers satisfactory results especially with mineral-based and/or surface modified adsorbents. In this review, an extensive list of various sorbents from the literature has been compiled and their adsorption capacities for nitrate removal as available in the literature are presented along with highlighting and discussing the key advancement on the preparation of novel adsorbents tested for nitrate removal.
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| 5. |
- Bhatnagar, Amit, et al.
(författare)
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Adsorptive removal of cobalt from aqueous solution by utilizing lemon peel as biosorbent
- 2010
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Ingår i: Biochemical engineering journal. - : Elsevier BV. - 1369-703X .- 1873-295X. ; 48:2, s. 181-186
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Tidskriftsartikel (refereegranskat)abstract
- The present study was undertaken to evaluate the feasibility of lemon peel waste for the removal of cobalt ions from aqueous solutions. Batch experiments were performed to study the adsorption of cobalt on lemon peel adsorbent. The maximum adsorption capacity of lemon peel adsorbent for cobalt removal was ca. 22 mg g(-1). Three simplified kinetic models viz. pseudo-first-order, pseudo-second-order, and Weber and Morris intraparticle diffusion models were tested to describe the adsorption process. Kinetic parameters, rate constants, equilibrium sorption capacities, and related correlation coefficients for kinetic models were determined. It was found that the present system of cobalt adsorption on lemon peel adsorbent could be described more favorably by the pseudo-second-order kinetic model. The adsorption process has been found to be exothermic. The results of the present study suggest that lemon peel waste can be used beneficially in treating industrial effluents containing heavy metal ions.
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| 6. |
- Bhatnagar, Amit, et al.
(författare)
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Application of Nanoadsorbents in Water Treatment
- 2014. - 1
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Ingår i: Nanomaterials for Environmental Protection. - Hoboken, NJ : John Wiley & Sons. - 9781118496978 - 9781118845530 ; , s. 237-247
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Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- Water treatment using the adsorption process has been found to be one of the most widely used methods, and several wastewater treatment plants around the world are operating on the principle of adsorption. Numerous adsorbents, for example, activated carbon, silica gel, zeolites, low-cost adsorbents from agro-industrial wastes, biosorbents, mineral-based adsorbents, and layered-double hydroxides, have been examined for their potential in the removal (adsorption) of diverse types of aquatic pollutants. In recent years, nanotechnology has emerged as one of the attractive technologies for water treatment, and various nanoadsorbents have been explored for water treatment applications. This chapter briefly summarizes the progress, advances, and applications of nanoadsorbents for water remediation. A compilation of various nanoadsorbents as reported in the literature has been presented, and their main findings related to water treatment applications are discussed. The chapter concludes with a discussion on the future perspectives in this field.
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| 7. |
- Bhatnagar, Amit, et al.
(författare)
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Applications of chitin- and chitosan-derivatives for the detoxification of water and wastewater - A short Review
- 2009
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Ingår i: Advances in Colloid and Interface Science. - : Elsevier BV. - 0001-8686 .- 1873-3727. ; 152, s. 26-38
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Tidskriftsartikel (refereegranskat)abstract
- Chitin and chitosan-derivatives have gained wide attention as effective biosorbents due to low cost and high contents of amino and hydroxyl functional groups which show significant adsorption potential for the removal of various aquatic pollutants. In this review, an extensive list of chitin- and chitosan-derivatives from vast literature has been compiled and their adsorption capacities for various aquatic pollutants as available in the literature are presented. This paper will give an overview of the principal results obtained during the treatment of water and wastewater utilizing chitin and chitosan-derivatives for the removal of: (a) metal cations and metal anions; (b) radionuclides; (c) different classes of dyes; (d) phenol and substituted phenols; (e) different anions and other miscellaneous pollutants. The review provides a summary of recent information obtained using batch studies and deals with the various adsorption mechanisms involved. It is evident from the literature survey that chitin- and chitosan-derivatives have shown good potential for the removal of various aquatic pollutants. However, still there is a need to find out the practical utility of such developed adsorbents on commercial scale.
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| 8. |
- Bhatnagar, Amit, et al.
(författare)
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Fluoride removal from water by adsorption : A review
- 2011
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Ingår i: Chemical Engineering Journal. - : Elsevier. - 1385-8947 .- 1873-3212. ; 171:3, s. 811-840
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Tidskriftsartikel (refereegranskat)abstract
- Fluoride contamination in drinking water due to natural and anthropogenic activities has been recognized as one of the major problems worldwide imposing a serious threat to human health. Among several treatment technologies applied for fluoride removal, adsorption process has been explored widely and offers satisfactory results especially with mineral-based and/or surface modified adsorbents. In this review, an extensive list of various adsorbents from literature has been compiled and their adsorption capacities under various conditions (pH, initial fluoride concentration, temperature, contact time, adsorbent surface charge, etc.) for fluoride removal as available in the literature are presented along with highlighting and discussing the key advancement on the preparation of novel adsorbents tested so far for fluoride removal. It is evident from the literature survey that various adsorbents have shown good potential for the removal of fluoride. However, still there is a need to find out the practical utility of such developed adsorbents on a commercial scale, leading to the improvement of pollution control.
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| 9. |
- Bhatnagar, Amit, et al.
(författare)
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Heavy metals adsorption by novel EDTA-modified chitosan-silica hybrid materials
- 2011
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Ingår i: Journal of Colloid and Interface Science. - : Elsevier BV. - 0021-9797 .- 1095-7103. ; 358:1, s. 261-267
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Tidskriftsartikel (refereegranskat)abstract
- Novel adsorbents were synthesized by functionalizing chitosan-silica hybrid materials with (ethylenediaminetetraacetic acid) EDTA ligands. The synthesized adsorbents were found to combine the advantages of both silica gel (high surface area, porosity, rigid structure) and chitosan (surface functionality). The Adsorption potential of hybrid materials was investigated using Co(II), Ni(II), Cd(II), and Pb(II) as target metals by varying experimental conditions such as pH, contact time, and initial metal concentration. The kinetic results revealed that the pore diffusion process played a key role in adsorption kinetics, which might be attributed to the porous structure of synthesized adsorbents. The obtained maximum adsorption capacities of the hybrid materials for the metal ions ranged from 0.25 to 0.63 mmol/g under the studied experimental conditions. The adsorbent with the highest chitosan content showed the best adsorption efficiency. Bi-Langmuir and Sips isotherm model fitting to experimental data suggested the surface heterogeneity of the prepared adsorbents. In multimetal solutions, the hybrid adsorbents showed the highest affinity toward Pb(II).
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| 10. |
- Bhatnagar, Amit, et al.
(författare)
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Nitrate removal from water by nano-alumina : Characterization and sorption studies
- 2010
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Ingår i: Chemical Engineering Journal. - : Elsevier. - 1385-8947 .- 1873-3212. ; 163:3, s. 317-323
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Tidskriftsartikel (refereegranskat)abstract
- The present study was conducted to evaluate the feasibility of nano-alumina for nitrate removal from aqueous solutions. The nature and morphology of sorbent was characterized by XRD, FTIR, BET and SEM analysis. Batch adsorption studies were performed as a function of contact time, initial nitrate concentration, temperature, pH and influence of other interfering anions. Nitrate sorption kinetics was well fitted by pseudo-second-order kinetic model. The maximum sorption capacity of nano-alumina for nitrate removal was found to be ca. 4.0 mg g(-1) at 25 +/- 2 degrees C. Maximum nitrate removal occurred at equilibrium pH ca. 4.4. The nitrate sorption has been well explained using Langmuir isotherm model. Results from this study demonstrated the potential utility of nano-alumina for nitrate removal from water.
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| 11. |
- Bhatnagar, Amit, et al.
(författare)
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Utilization of agro-industrial and municipal waste materials as potential adsorbents for water treatment- A Review
- 2010
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Ingår i: Chemical Engineering Journal. - : Elsevier BV. - 1385-8947 .- 1873-3212. ; 157:2-3, s. 277-296
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Tidskriftsartikel (refereegranskat)abstract
- Adsorption process has been proven one of the best water treatment technologies around the world and activated carbon is undoubtedly considered as universal adsorbent for the removal of diverse types of pollutants from water. However, widespread use of commercial activated carbon is sometimes restricted due to its higher costs. Attempts have been made to develop inexpensive adsorbents utilizing numerous agro-industrial and municipal waste materials. Use of waste materials as low-cost adsorbents is attractive due to their contribution in the reduction of costs for waste disposal, therefore contributing to environmental protection. In this review, an extensive list of low-cost adsorbents (prepared by utilizing different types of waste materials) from vast literature has been compiled and their adsorption capacities for various aquatic pollutants as available in the literature are presented. It is evident from the literature survey that various low-cost adsorbents have shown good potential for the removal of various aquatic pollutants. However, there are few issues and drawbacks on the use of low-cost adsorbents in water treatment that have been discussed in this paper. Additionally, more research is needed to find the practical utility of low-cost adsorbents on commercial scale.
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| 12. |
- Ibounig, Thomas, et al.
(författare)
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Concordance of shoulder symptoms and imaging findings: a protocol for the Finnish Imaging of Shoulder (FIMAGE) study
- 2023
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Ingår i: BMJ open. - 2044-6055. ; 13:12
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Tidskriftsartikel (refereegranskat)abstract
- INTRODUCTION: Shoulder pain is a substantial medical and socioeconomic problem in most societies, affecting the ability to work or carry out leisure time activities as well as subsequently influencing physical and psychological well-being. According to a nationwide survey in Finland, 27% of the population reported shoulder pain within the last 30 days. In clinical practice, imaging findings of structural abnormalities are typically thought to explain symptoms, even though such findings are also prevalent in asymptomatic individuals, particularly with increasing age. Overall, there is a paucity of high-quality evidence on the prevalence, clinical relevance and prognosis of 'abnormal' imaging findings of the shoulder.The aim of the Finnish Imaging of Shoulder (FIMAGE) study is fourfold: to assess (1) the prevalence of shoulder symptoms and the most common anatomical variants and imaging abnormalities of the shoulder; (2) the concordance between shoulder symptoms, function and imaging abnormalities; (3) the most important determinants of symptoms, function and imaging abnormalities; and (4) the course of shoulder complaints over 5 years. METHODS: The FIMAGE target population of 600 participants, aged 40-75 years, will be randomly selected from a nationally representative general population sample of 9922 individuals originally recruited for the Finnish Health 2000 Survey. On giving informed consent, the participants will be invited to a clinical visit that includes assessment of general health, shoulder symptoms, bilateral shoulder examination and imaging of both shoulders with plain radiography and MRI. ETHICS AND DISSEMINATION: The study has been approved by the Institutional Review Board of the Helsinki and Uusimaa Hospital District. The findings will be published according to the Strengthening the Reporting of Observational Studies in Epidemiology criteria.
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| 13. |
- Kaur, Parminder, et al.
(författare)
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Photoelectrocatalytic treatment of municipal wastewater with emerging concern pollutants using modified multi-layer catalytic anode
- 2023
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Ingår i: Chemosphere. - : Elsevier Ltd. - 0045-6535 .- 1879-1298. ; 339
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Tidskriftsartikel (refereegranskat)abstract
- Municipal wastewater contains emergent chemical and biological pollutants that are resistant to conventional wastewater treatments. Therefore, the focus of the current study was to address the challenge of removing emergent chemical and biological pollutants present in municipal wastewater. To achieve this, a photo electro-catalytic (PEC) treatment approach was employed, focusing on the removal of both micro and biological pollutants that are of emergent concern, as well as the reduction of Chemical Oxidation Demand (COD) and Total Organic Carbon (TOC). The treatment involved the use of a modified multi-layer catalytic anode photo-electroactive anode as an effective anode for PEC treatment of municipal wastewater. In the continuous mode of operation, %COD removal was optimized for the treatment of municipal wastewater under Ultra-Violet C (UVc), 280 nm, and Visible (Vis) radiation, 400 nm. Therefore, a comparative study was performed to investigate the effect of Vis radiation on %COD removal, micropollutants removal, and disinfection of municipal wastewater. Micropollutants present in municipal wastewater were effectively oxidized/degraded with the highest reduction rate between 100% and 80% under the influence of UVc and Vis radiation respectively by the PEC treatment process. Disinfection of various microorganisms present in the wastewater with the effect of UVc and Vis assisted PEC treatment was also monitored. Overall, 75–80% of the disinfection of municipal wastewater was contributed by the modified multi-layer catalytic anode. The UVc in the PEC system, contributes approximately 20–25% to the overall disinfection of municipal wastewater.
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| 14. |
- Kumar, Eva, et al.
(författare)
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Defluoridation from aqueous solutions by nano-alumina : Characterization and sorption studies
- 2011
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Ingår i: Journal of Hazardous Materials. - : Elsevier. - 0304-3894 .- 1873-3336. ; 186:2-3, s. 1042-1049
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Tidskriftsartikel (refereegranskat)abstract
- The present study was conducted to evaluate the feasibility of nano-alumina (Al(2)O(3)) for fluoride adsorption from aqueous solutions. The nature and morphology of pure and fluoride-sorbed nano-alumina were characterized by SEM with EDX, XRD, and FTIR analysis. Batch adsorption studies were performed as a function of contact time, initial fluoride concentration, temperature, pH and influence of competing anions. Fluoride sorption kinetics was well fitted by pseudo-second-order model. The maximum sorption capacity of nano-alumina for fluoride removal was found to be 14.0 mg g(-1) at 25 degrees C. Maximum fluoride removal occurred at pH 6.15. The fluoride sorption has been well explained using Langmuir isotherm model. Fluoride sorption was mainly influenced by the presence of PO(4)(3-), SO(4)(2-) and CO(3)(2-) ions.
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| 15. |
- Kumar, Eva, et al.
(författare)
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Interaction of anionic pollutants with Al-based adsorbents in aqueous media – A review
- 2014
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Ingår i: Chemical Engineering Journal. - : Elsevier BV. - 1385-8947 .- 1873-3212. ; 241, s. 443-456
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Tidskriftsartikel (refereegranskat)abstract
- Many anionic pollutants (e.g., fluoride, nitrate and nitrite, bromate, phosphate, arsenate and arsenite, selenate and selenite, perchlorate) have been detected in surface and groundwater in different parts of the world and strict measures are being taken to minimize their concentrations and to control their mobility in aqueous media. Mineral surfaces, in general, have shown enhanced uptake of many anionic pollutants. Various phases of aluminum (Al) oxides, hydroxides and oxyhydroxide are increasingly being employed as adsorbents for the detoxification of water and wastewater contaminated with anionic pollutants. Understanding the structural properties and morphology of adsorbents is important in order to gain knowledge about the governing mechanism behind the adsorption of anions by these adsorbents. The adsorption ability of aluminum oxides, hydroxides and oxyhydroxide depends on several key factors including properties of the adsorbent (surface area, pore size, pHpzc, porosity) and that of the adsorbates. This paper provides an overview of the physical and chemical properties of various aluminum oxides, hydroxides and oxyhydroxides and their application in water and wastewater treatment with the focus on the removal of anionic pollutants. Furthermore, the performance of these minerals and that of the synthetically prepared hybrid adsorbents (containing Al-minerals) for the adsorption of various anions has been reviewed with an emphasis on the behavior of adsorbent-water interface in presence of the anionic pollutants.
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| 16. |
- Kumar, Eva
(författare)
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Removal of Inorganic Anionic Pollutants from Water using Adsorption Technology
- 2013
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- In the era of urbanization, industrialization and population growth, groundwater and drinking water sources are getting adversely polluted due to the addition of different toxic contaminants including inorganic anionic pollutants. The inorganic anions are of serious concern due to their adverse health effects on humans, even when present at very low concentrations in water. Adsorption process is an attractive method for the removal of anions as compared to other water treatment technologies in terms of cost, simplicity of design and operation. In this study, granular ferric hydroxide (GFH) and nano-Al2O3 were tested for the removal of fluoride, perchlorate and nitrate anions from aqueous solutions. Different experimental parameters (viz. pH, agitation time, adsorbate concentration, temperature, competing anions) have been studied to optimize the adsorption process. The maximum adsorption capacity of 7.0 mg g-1 (at pH 6.0-7.0) and 20.0 mg g-1 (at pH 6.0-6.5) for fluoride and perchlorate, respectively was achieved using GFH at 25 oC. Adsorption kinetics of fluoride by GFH was favorably explained with pseudo-first-order, while perchlorate adsorption kinetics followed pseudo-second-order model. The Langmuir model explained the adsorption isotherms of fluoride and perchlorate by GFH. The Raman spectroscopy results revealed that perchlorate was adsorbed through electrostatic attraction between perchlorate and positively charged GFH surface sites. The adsorption efficiencies achieved by nano-Al2O3 for nitrate and fluoride were 4.0 mg g-1 (at pH ~4.4) and 14.0 mg g-1 (at pH ~6.15), respectively at 25 oC. Kinetics and isotherms of fluoride and nitrate by nano-Al2O3 were well-explained by pseudo-second-order model and Langmuir isotherm model, respectively. The FTIR and EDX results reveal that aluminum-fluoro complexes are formed due to the interaction between fluoride and nano-Al2O3 moieties. In all the cases, the most influencing anions were the ones that compete for similar binding sites on the adsorbent surface. Results from this study will be helpful in demonstrating potential utility of the tested adsorbents for the removal of different anions from water and provide an insight into the adsorbent-adsorbate (anions) interactions in the aqueous media.
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| 17. |
- Matilainen, Annu, et al.
(författare)
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An overview of the methods used in the characterization of natural organic matter (NOM) in relation to drinking water treatment
- 2011
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Ingår i: Chemosphere. - : Elsevier BV. - 0045-6535 .- 1879-1298. ; 83:11, s. 1431-1442
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Tidskriftsartikel (refereegranskat)abstract
- Natural organic matter (NOM) is found in all surface, ground and soil waters. During recent decades, reports worldwide show a continuing increase in the color and NOM of the surface water, which has an adverse affect on drinking water purification. For several practical and hygienic reasons, the presence of NOM is undesirable in drinking water. Various technologies have been proposed for NOM removal with varying degrees of success. The properties and amount of NOM, however, can significantly affect the process efficiency. In order to improve and optimise these processes, the characterisation and quantification of NOM at different purification and treatment processes stages is important. It is also important to be able to understand and predict the reactivity of NOM or its fractions in different steps of the treatment. Methods used in the characterisation of NOM include resin adsorption, size exclusion chromatography (SEC), nuclear magnetic resonance (NMR) spectroscopy, and fluorescence spectroscopy. The amount of NOM in water has been predicted with parameters including UV-Vis, total organic carbon (TOC), and specific UV-absorbance (SUVA). Recently, methods by which NOM structures can be more precisely determined have been developed; pyrolysis gas chromatography-mass spectrometry (Py-GC-MS), multidimensional NMR techniques, and Fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS). The present review focuses on the methods used for characterisation and quantification of NOM in relation to drinking water treatment.
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| 18. |
- Qi, Kezhen, et al.
(författare)
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Enhanced photocatalytic activity of anatase-TiO2 nanoparticles by fullerene modification : A theoretical and experimental study
- 2016
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Ingår i: Applied Surface Science. - : Elsevier BV. - 0169-4332 .- 1873-5584. ; 387, s. 750-758
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Tidskriftsartikel (refereegranskat)abstract
- A series of fullerene (C-60)-modified anatase TiO2 (a-TiO2) nanocomposites with different weight loadings of C-60 were successfully synthesized by a simple solution phase method. The as-prepared C-60@a-TiO2 nanocomposites were characterized by X-ray diffraction (XRD), Raman spectroscopy, Brunauer-Emmett-Teller (BET), UV-vis diffuse reflectance absorption spectra (DRS), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM) and electron energy loss spectroscopy (EELS). The photocatalytic degradation of methylene blue (MB) by the neat a-TiO2 and C-60@a-TiO2 nanocomposites was investigated under UV-A light irradiation, demonstrating that C-60 effectively enhances the photocatalytic activity of a-TiO2 nanoparticles with an optimal amount of 2.0 wt%. By combining with the density functional theory (DFT) calculations, we investigated the electronic structures of C-60@a-TiO2 hetero-interfaces to reveal the underlying principle of the C-60 loading on the photocatalytic activity. It was found that the incorporation of C-60 on the a-TiO2 surface not only narrowed the band gap, but also introduced an additional doping state between the valance and conduction band. Therefore, the presence of intermediate electronic state will in turn contribute to the efficient charge separation and enhanced light adsorption for the C-60@a-TiO2 nanocomposites, resulting in an improved photocatalytic performance.
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| 19. |
- Qi, Kezhen, et al.
(författare)
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Hierarchical alpha-MnS microspheres : Solvothermal synthesis and growth mechanism
- 2016
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Ingår i: Materials letters (General ed.). - : Elsevier BV. - 0167-577X .- 1873-4979. ; 166, s. 116-120
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Tidskriftsartikel (refereegranskat)abstract
- Hierarchical-like alpha-MnS microspheres have been successfully synthesized via a simple solvothermal route using L-Cystein as both sulfur source and capping agent. X-ray diffraction (XRD) analysis confirmed that these hierarchical microspheres were made of alpha-phase MnS. Morphological studies performed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) methods showed that the alpha-MnS hierarchical microspheres are obtained from the nanocubes by self-assembly due to the main driving force of the minimization of overall surface energy. It is highly expected this research can provide a useful fundamental understanding of shape-controlled synthesis of the semiconductor material with hierarchical microstructures.
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| 20. |
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| 21. |
- Zhang, Yunfan, et al.
(författare)
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Coprecipitates Synthesis of CaIn2O4 and Its Photocatalytic Degradation of Methylene Blue by Visible Light Irradiation
- 2014
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Ingår i: Industrial & Engineering Chemistry Research. - : American Chemical Society (ACS). - 0888-5885 .- 1520-5045. ; 53:29, s. 11720-11726
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Tidskriftsartikel (refereegranskat)abstract
- Visible light-activated photocatalyst calcium indate (CaIn2O4) has been successfully prepared by a new approach with lower temperature calcinations. The sub-micrometer-sized samples were characterized by X-ray diffraction, field-emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, and UV-vis diffuse reflectance spectroscopy. High-purity CaIn2O4 particles were synthesized by controlling the sintering temperature and their photocatalytic performance were evaluated. Under visible light irradiation, 10 ppm of methylene blue solution was effectively degraded in 3.0 h. The excellent photocatalytic activity of CaIn2O4 is attributed to the high purity, small particle size, and large surface area because of lower sintering temperature by thermal decomposition of metal oxalate precursor.
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| 22. |
- Zhang, Yunfan, et al.
(författare)
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Enhanced solar photocatalytic activity of Er3+ : YAlO3-loaded BiPO4 composite
- 2015
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Ingår i: Journal of Industrial and Engineering Chemistry. - : Elsevier BV. - 1226-086X .- 1876-794X. ; 24, s. 161-165
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Tidskriftsartikel (refereegranskat)abstract
- Er3+:YAlO3 loaded BiPO4 were successfully synthesized by a simple heat treatment approach in order to enhance the photocatalytic efficiency of BiPO4. Comparing with the simple substance of BiPO4, the composite system showed the better efficiency on photodegradation of Methlyene Blue (MB) solution under a simulated solar light irradiation. The relationship between loading amount and degradation rate was also investigated. It is found that the optimal loading amount of Er3+:YAlO3 is 7 wt%. The recycling test of selected sample was carried out to study the stability of the Er3+:YAlO3 loaded BiPO4 system. The composite materials were finally characterized by field-emission scanning electron microscopy (SEM), X-ray diffraction (XRD) and UV-visible diffuse reflectance spectroscopy (UV-vis DRS). Based on the findings a possible mechanism has been proposed. The existence of luminescence agent (Er3+-doped YAlO3) and the occurrence of upconversion luminescence process have been related with the enhanced photodegradation of MB over composite system. (C) 2014 The Korean Society of Industrial and Engineering Chemistry.
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