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Kuo KY, Chen SH, Hsiao PH, Lee JT, Chen CY. Day-night active photocatalysts obtained through effective incorporation of Au@Cu xS nanoparticles onto ZnO nanowalls. JOURNAL OF HAZARDOUS MATERIALS 2022; 421:126674. [PMID: 34315025 DOI: 10.1016/j.jhazmat.2021.126674] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2021] [Revised: 07/09/2021] [Accepted: 07/15/2021] [Indexed: 06/13/2023]
Abstract
Photocatalytic degradation of organic dyes has been considered one of the promising solutions that enabled to effectively treat the demanding pollutants in wastewater. Yet, insight into the photocatalytic process under both illumination and dark conditions were hitherto missing. Herein, by virtue of incorporating the core-shell Au@CuxS nanoparticles to the ZnO nanowalls synthesized via all-solution synthesis, the intriguing heterostructures allowed to trigger the extraordinary capability of dye degradation either under light irradiance or dark environment. It was found that the coexistence of bi-constituted Cu2S/CuS shells on Au nanoparticles obtained with turning the concentrations of sulfurization acted as the decisive role on day-night active degradation performance, where the degradation efficiency was more than 8.3 times beyond sole ZnO sheets. The mediation of remarkable visible-light absorption and efficient charge separation due to band alignment of heterojunctions were responsible for the improved photodegradation efficiency under visible illuminations. Moreover, at dark environment, the involving peroxidase-like activity of CuxS shells with the mediation of Au nanoparticles facilitated the catalytic formation of hydroxyl radicals, manifesting the oxidative degradation of MB dye. Such all-day active photocatalysts further displayed the capability for the recycling treatment of MB dye, which offered the pathways to potentially treat the organic wastewater.
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Affiliation(s)
- Kuan-Yi Kuo
- Department of Materials Science and Engineering, National Cheng Kung University, Tainan 70101, Taiwan
| | - Shih-Hsiu Chen
- Department of Materials Science and Engineering, National Cheng Kung University, Tainan 70101, Taiwan
| | - Po-Hsuan Hsiao
- Department of Materials Science and Engineering, National Cheng Kung University, Tainan 70101, Taiwan
| | - Jui-Teng Lee
- Department of Materials Science and Engineering, National Cheng Kung University, Tainan 70101, Taiwan
| | - Chia-Yun Chen
- Department of Materials Science and Engineering, National Cheng Kung University, Tainan 70101, Taiwan; Hierarchical Green-Energy Materials (Hi-GEM) Research Center, National Cheng Kung University, Tainan 70101, Taiwan.
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2
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Hammouche J, Daoudi K, Columbus S, Ziad R, Ramachandran K, Gaidi M. Structural and morphological optimization of Ni doped ZnO decorated silicon nanowires for photocatalytic degradation of methylene blue. INORG CHEM COMMUN 2021. [DOI: 10.1016/j.inoche.2021.108763] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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Immobilization of TiO2 Nanoparticles in Cement for Improved Photocatalytic Reactivity and Treatment of Organic Pollutants. Catalysts 2021. [DOI: 10.3390/catal11080938] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Non-point organic pollutants in stormwater are a growing problem in the urban environment which lack effective and efficient treatment technologies. Incorporation of conventional wastewater techniques within stormwater management practices could fundamentally change how stormwater quality is managed because contaminants can be degraded during stormwater transport or storage. This study investigated the photocatalytic reactivity of titanium dioxide functionalized with maleic anhydride (Ti-MAH) within cement pastes when compared to ordinary Portland cement. Preparation of Ti-MAH was performed by permanently bonding maleic anhydride to titanium in methanol, drying and powdering the residual material, and then inter-grinding the preparation with cement during mixing. When compared with OPC, the Ti-MAH cured cement paste is more reactive under a wider range of light wavelengths, possesses a higher band gap, sustains this heightened reactivity over multiple testing iterations, and treats organics effectively (>95% methylene blue removal). Amorphous silica within calcium-silica-hydrate, C-S-H, is theorized to bond to the powdered Ti-MAH during curing. Verification of silicon bonding to the titanium by way of MAH was demonstrated by FTIR spectra, SEM imagery, and XRD. Creating a sustainable and passive photocatalytic cement that precisely bonds silica to Ti-MAH is useful for organic contaminants in urban stormwater, but use can translate to other applications because Ti-MAH bonds readily with any amorphous silica such as glass materials, paints and coatings, optics, and LEDS, among many others.
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4
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Optical Management of CQD/AgNP@SiNW Arrays with Highly Efficient Capability of Dye Degradation. Catalysts 2021. [DOI: 10.3390/catal11030399] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
The facile synthetic method for the preparation of incorporated carbon quantum dots (CQDs)/Ag nanoparticles (AgNPs) with well-aligned silicon nanowire (SiNW) arrays is demonstrated, offering the superior photodegradation capabilities covering UV to visible wavelength regions. By examining the morphology, microstructure, crystallinity, chemical feature, surface groups, light-emitting, and reflection characteristics, these hybrid heterostructures are systematically identified. Moreover, the involving degradation kinetics, band diagram, cycling capability, and underlying mechanism of photodegradation are investigated, validating their remarkable and reliable photocatalytic performances contributed from the strongly reduced light reflectivity, superior capability of charge separation, and sound wettability with dye solutions.
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Gaidi M, Daoudi K, Columbus S, Hajjaji A, Khakani MAE, Bessais B. Enhanced photocatalytic activities of silicon nanowires/graphene oxide nanocomposite: Effect of etching parameters. J Environ Sci (China) 2021; 101:123-134. [PMID: 33334508 DOI: 10.1016/j.jes.2020.08.010] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Revised: 08/06/2020] [Accepted: 08/11/2020] [Indexed: 05/08/2023]
Abstract
Homogeneous and vertically aligned silicon nanowires (SiNWs) were successfully fabricated using silver assisted chemical etching technique. The prepared samples were characterized using scanning electron microscopy, transmission electron microscopy and atomic force microscopy. Photocatalytic degradation properties of graphene oxide (GO) modified SiNWs have been investigated. We found that the SiNWs morphology depends on etching time and etchant composition. The SiNWs length could be tuned from 1 to 42 µm, respectively when varying the etching time from 5 to 30 min. The etchant concentration was found to accelerate the etching process; doubling the concentrations increases the length of the SiNWs by a factor of two for fixed etching time. Changes in bundle morphology were also studied as function of etching parameters. The SiNWs diameter was found to be independent of etching time or etchant composition while the size of the SiNWs bundle increases with increasing etching time and etchant concentration. The addition of GO was found to improve significantly the photocatalytic activity of SiNWs. A strong correlation between etching parameters and photocatalysis efficiency has been observed, mainly for SiNWs prepared at optimum etching time and etchant concentrations of 10 min and 4:1:8. A degradation of 92% was obtained which further improved to 96% by addition of hydrogen peroxide. Only degradation efficiency of 16% and 31% has been observed for bare Si and GO/bare Si samples respectively. The obtained results demonstrate that the developed SiNWs/GO composite exhibits excellent photocatalytic performance and could be used as potential platform for the degradation of organic pollutants.
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Affiliation(s)
- Mounir Gaidi
- Department of Applied Physics and Astronomy, University of Sharjah, Sharjah 27272, United Arab Emirates Sharjah; Centre for Advanced Materials Research, Research Institute of Sciences and Engineering, University of Sharjah, Sharjah 27272, United Arab Emirates Sharjah; Laboratoire de Photovoltaïque, Centre de Recherches et des Technologies de l'Energie, Technopole de Borj-Cédria, Hammam-Lif 2050, Tunisia.
| | - Kais Daoudi
- Department of Applied Physics and Astronomy, University of Sharjah, Sharjah 27272, United Arab Emirates Sharjah; Centre for Advanced Materials Research, Research Institute of Sciences and Engineering, University of Sharjah, Sharjah 27272, United Arab Emirates Sharjah
| | - Soumya Columbus
- Centre for Advanced Materials Research, Research Institute of Sciences and Engineering, University of Sharjah, Sharjah 27272, United Arab Emirates Sharjah; Sharjah Research Academy, University City, Sharjah 60999, United Arab Emirates Sharjah
| | - Anouar Hajjaji
- Laboratoire de Photovoltaïque, Centre de Recherches et des Technologies de l'Energie, Technopole de Borj-Cédria, Hammam-Lif 2050, Tunisia
| | - My Ali El Khakani
- Institut National de la Recherche Scientifique (INRS), INRS-Énergie, Matériaux et Télécommunications, 1650, Blvd. Lionel-Boulet, Varennes, QC J3X-1S2, Canada
| | - Brahim Bessais
- Laboratoire de Photovoltaïque, Centre de Recherches et des Technologies de l'Energie, Technopole de Borj-Cédria, Hammam-Lif 2050, Tunisia
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Sayadi MH, Ahmadpour N, Homaeigohar S. Photocatalytic and Antibacterial Properties of Ag-CuFe 2O 4@WO 3 Magnetic Nanocomposite. NANOMATERIALS (BASEL, SWITZERLAND) 2021; 11:298. [PMID: 33498950 PMCID: PMC7911755 DOI: 10.3390/nano11020298] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/24/2020] [Revised: 01/18/2021] [Accepted: 01/19/2021] [Indexed: 01/24/2023]
Abstract
This study aimed to synthesize a new magnetic photocatalytic nanosystem composed of Ag-CuFe2O4@WO3 and to investigate its photodegradation efficiency for two drug pollutants of Gemfibrozil (GEM) and Tamoxifen (TAM) under Ultraviolet (UV) light irradiation. In this regard, the effect of pH, catalyst dosage, and drug concentration was thoroughly determined. The largest photodegradation level for GEM (81%) and TAM (83%) was achieved at pH 5, a photocatalyst dosage of 0.2 g/L, drug concentration of 5 mg/L, and contact time of 150 min. The drug photodegradation process followed the pseudo first-order kinetic model. In addition to the photodegradation effect, the nanocomposites were proved to be efficient in terms of antibacterial activity, proportional to the Ag doping level. The Ag-CuFe2O4@WO3 nanocomposite exhibited a stable, efficient performance without an obvious catalytic loss after five successive cycles. Taken together, the developed magnetic photocatalyst is able to simultaneously disinfect wastewater streams and to degrade pharmaceutical contaminants and thus shows a promising potential for purification of multi-contaminant water systems.
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Affiliation(s)
- Mohammad Hossein Sayadi
- Department of Environmental Engineering, Faculty of Natural Resources and Environment, University of Birjand, Birjand 9717434765, Iran;
- Department of Environmental Engineering, Faculty of Agriculture and Natural Resources, Ardakan University, Ardakan 8951895491, Iran
| | - Najmeh Ahmadpour
- Department of Environmental Engineering, Faculty of Natural Resources and Environment, University of Birjand, Birjand 9717434765, Iran;
| | - Shahin Homaeigohar
- School of Science & Engineering, University of Dundee, Dundee DD1 4HN, UK
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Hsiao PH, Wei TC, Chen CY. Stability improvement of Cu(ii)-doped ZnS/ZnO photodetectors prepared with a facile solution-processing method. Inorg Chem Front 2021. [DOI: 10.1039/d0qi00937g] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The solution-processed growth of Cu2+ doped ZnS as protective coatings on ZnO nanorods with improved photoresponsivity and stability was presented.
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Affiliation(s)
- Po-Hsuan Hsiao
- Department of Materials Science and Engineering
- National Cheng Kung University
- Tainan 70101
- Taiwan
| | - Ta-Cheng Wei
- Department of Materials Science and Engineering
- National Cheng Kung University
- Tainan 70101
- Taiwan
| | - Chia-Yun Chen
- Department of Materials Science and Engineering
- National Cheng Kung University
- Tainan 70101
- Taiwan
- Hierarchical Green-Energy Materials (Hi-GEM) Research Center
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8
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Singh PK, Kuo KY, Lee JT, Hsiao PH, Juan JC, Duong HP, Chen CY. Synergistic absorbents based on SnFe2O4@ZnO nanoparticles decorated with reduced graphene oxide for highly efficient dye adsorption at room temperature. RSC Adv 2021; 11:17840-17848. [PMID: 35480223 PMCID: PMC9033190 DOI: 10.1039/d1ra02317a] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Accepted: 05/05/2021] [Indexed: 11/21/2022] Open
Abstract
Recently, adsorption techniques have emerged as practical and effective methods for removing organic dyes, dramatically extending practical capabilities for treating deleterious pollutants in wastewater. However, an urgent issue restricting the performance of these techniques is that no available absorbents that can be used to treat both cationic and anionic organic dyes have been made with simple and reliable methods until now. Herein, we report a green synthetic strategy for the preparation of SnFe2O4/ZnO nanoparticles decorated on reduced graphene oxide (rGO), exhibiting a remarkably large surface area (120.33 m2 g−1). Substantial adsorption efficiency for removing MB dye was achieved, with 91.3% removal within 20 min at room temperature, and efficiencies of 79.6 to 92.8% are maintained as the pH conditions are varied from 3 to 11. Moreover, under mixed-dye conditions, involving MB, RhB, MO, RB5, and R6G organic materials, with dye concentrations ranging from 0.005 mM to 0.09 mM, an adsorption efficiency of above 50% can be reliably reached within 20 min. Such striking features can be interpreted as arising from a synergistic effect involving the hybrid composite based on a rGO matrix with negative charge and the dispersed SnFe2O4/ZnO nanoparticles with positive charge, additionally offering abundant adsorptive sites to allow reliable dye-adsorption kinetics. Magnetically separable SnFe2O4/ZnO nanoparticles decorated on rGO sheets with remarkable dye adsorption capabilities are demonstrated.![]()
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Affiliation(s)
- Pawan Kumar Singh
- Department of Materials Science and Engineering
- National Cheng Kung University
- Tainan 70101
- Taiwan
| | - Kuan-Yi Kuo
- Department of Materials Science and Engineering
- National Cheng Kung University
- Tainan 70101
- Taiwan
| | - Jui-Teng Lee
- Department of Materials Science and Engineering
- National Cheng Kung University
- Tainan 70101
- Taiwan
| | - Po-Hsuan Hsiao
- Department of Materials Science and Engineering
- National Cheng Kung University
- Tainan 70101
- Taiwan
| | - Joon Ching Juan
- Nanotechnology & Catalysis Research Centre
- Institute for Advanced Studies
- University of Malaya
- 50603 Kuala Lumpur
- Malaysia
| | - Hong Phan Duong
- The University of Danang
- University of Science and Technology
- Vietnam
| | - Chia-Yun Chen
- Department of Materials Science and Engineering
- National Cheng Kung University
- Tainan 70101
- Taiwan
- Hierarchical Green-Energy Materials (Hi-GEM) Research Center
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9
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Electric and Photocatalytic Properties of Graphene Oxide Depending on the Degree of Its Reduction. NANOMATERIALS 2020; 10:nano10112313. [PMID: 33266500 PMCID: PMC7700189 DOI: 10.3390/nano10112313] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Revised: 11/14/2020] [Accepted: 11/15/2020] [Indexed: 11/17/2022]
Abstract
When graphene oxide is reduced, the functional groups are released and the structure becomes more ordered. The degree of reduction might be tunable with the process parameters. In our work, graphene oxide is prepared and the effect of thermal and chemical reduction is investigated. The samples are characterized with TG/DTA-MS, SEM-EDX, TEM, XPS, ATR-FTIR, Raman spectroscopy and XRD. Their electrical resistance, cyclic voltammetry and photocatalytic activity data are investigated. The conductivity can be varied by several orders of magnitude, offering a tool to match its electrical properties to certain applications. Low temperature reduction in air offers a material with the highest capacitance, which might be used in supercapacitors. The bare graphene oxide has considerably larger photocatalytic activity than P25 TiO2. Reduction decreases the activity, meaning that reduced graphene oxide can be used as an electron sink in composite photocatalysts, but does not contribute to the photocatalytic activity by itself.
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10
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Chien PJ, Wei TC, Chen CY. High-Speed and Direction-Controlled Formation of Silicon Nanowire Arrays Assisted by Electric Field. NANOSCALE RESEARCH LETTERS 2020; 15:25. [PMID: 32002703 PMCID: PMC6990330 DOI: 10.1186/s11671-020-3259-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2019] [Accepted: 01/20/2020] [Indexed: 06/01/2023]
Abstract
Metal-assisted chemical etching (MaCE), a low-cost and versatile method was considered a promising technique for preparing silicon nanowires (SiNWs), yet the lack of well controlling the injected holes within Si might reduce the etching rate, create the unwanted sidewall etching, and degrade the structural uniformity. Herein, in this study, the bias-modulated MaCE process was performed, showing the etching rates more than four times of magnitude than that of typical bias-free MaCE with large-area uniformity. It was found that the field-mediated hole rectification overwhelmed the effect of retarded diffusivity from reactive ions, and thus the dynamics of distributed etching were therefore transferred to the directional etching behaviors. In addition, the etching orientation could be also manipulated with the external bias. The results demonstrated that the etching direction was switched toward the slanted features by varying the electric polarization, creating the special slanted/vertical NW arrays, which possessed the superior antireflection characteristics than the conventional vertically aligned features.
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Affiliation(s)
- Pin-Ju Chien
- Department of Materials Science and Engineering, National Cheng Kung University, Tainan, 70101, Taiwan
| | - Ta-Cheng Wei
- Department of Materials Science and Engineering, National Cheng Kung University, Tainan, 70101, Taiwan
| | - Chia-Yun Chen
- Department of Materials Science and Engineering, National Cheng Kung University, Tainan, 70101, Taiwan.
- Hierarchical Green-Energy Materials (Hi-GEM) Research Center, National Cheng Kung University, Tainan, 70101, Taiwan.
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11
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Photochromic and Photocatalytic Properties of Ultra-Small PVP-Stabilized WO 3 Nanoparticles. Molecules 2019; 25:molecules25010154. [PMID: 31905983 PMCID: PMC6982781 DOI: 10.3390/molecules25010154] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2019] [Revised: 12/25/2019] [Accepted: 12/26/2019] [Indexed: 11/30/2022] Open
Abstract
Tungsten oxide-based bulk and nanocrystalline materials are widely used as photocatalytic and photo- and electrochromic materials, as well as materials for biomedical applications. In our work, we focused our attention on the effect of sodium cations on the structure and photochromic properties of the WO3@PVP aqueous sols. To establish the effect, the sols were synthesized by either simple pH adjusting of sodium or ammonium tungstates’ solutions, or using an ion exchange technique to remove the cations from the materials to the greatest possible extent. We showed that the presence of sodium cations in WO3@PVP favors the formation of reduced tungsten species (W+5) upon UV irradiation of the materials, strongly affecting their photochromic and photocatalytic properties. The pronounced photoreductive properties of WO3@PVP sols in photocatalytic reactions were demonstrated. Due to photoreductive properties, photochromic sols of tungsten oxide can act as effective photoprotectors in photooxidation processes. We believe that our work provides a considerable contribution to the elucidation of photochromic and redox phenomena in WO3-based materials.
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Dey K, Ganguli S, Alam MS. Benign Hydrothermal Synthesis of N‐doped TiO
2
and TiO
2
‐CoS Nanostructures for Enhanced Visible‐Light Driven Photocatalytic Activity. ChemistrySelect 2019. [DOI: 10.1002/slct.201903406] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Kamol Dey
- Biomaterials Research Laboratory, Department of Applied Chemistry and Chemical Engineering, Faculty of ScienceUniversity of Chittagong Chittagong- 4331 Bangladesh
- Department of Mechanical and Industrial EngineeringUniversity of Brescia Brescia- 25123 Italy
| | - Sumon Ganguli
- Biomaterials Research Laboratory, Department of Applied Chemistry and Chemical Engineering, Faculty of ScienceUniversity of Chittagong Chittagong- 4331 Bangladesh
| | - M. S. Alam
- Department of Physics, Faculty of ScienceUniversity of Chittagong Chittagong- 4331 Bangladesh
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13
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Hsiao PH, Chen CY. Insights for Realizing Ultrasensitive Colorimetric Detection of Glucose Based on Carbon/Silver Core/Shell Nanodots. ACS APPLIED BIO MATERIALS 2019; 2:2528-2538. [DOI: 10.1021/acsabm.9b00228] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Po-Hsuan Hsiao
- Department of Materials Science and Engineering, National Cheng Kung University, Tainan 70101, Taiwan
| | - Chia-Yun Chen
- Department of Materials Science and Engineering, National Cheng Kung University, Tainan 70101, Taiwan
- Hierarchical Green-Energy Materials (Hi-GEM) Research Center, National Cheng Kung University, Tainan 70101, Taiwan
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14
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Powder and Nanotubes Titania Modified by Dye Sensitization as Photocatalysts for the Organic Pollutants Elimination. NANOMATERIALS 2019; 9:nano9040517. [PMID: 30987003 PMCID: PMC6523326 DOI: 10.3390/nano9040517] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/18/2019] [Revised: 03/29/2019] [Accepted: 03/29/2019] [Indexed: 11/17/2022]
Abstract
In this study, titanium dioxide powder obtained by the sol-gel method and TiO₂ nanotubes, were prepared. In order to increase the TiO₂ photoactivity, the powders and nanotubes obtained were modified by dye sensitization treatment during the oxide synthesis. The sensitizers applied were Quinizarin (Q) and Zinc protoporphyrin (P). The materials synthesized were extensively characterized and it was found that the dye sensitization treatment leads to modify the optical and surface properties of Titania. It was also found that the effectiveness of the dye-sensitized catalysts in the phenol and methyl orange (MO) photodegradation strongly depends on the dye sensitizer employed. Thus, the highest degradation rate for MO was obtained over the conventional Q-TiO₂ photocatalyst. In the case of the nanotubes series, the most effective photocatalyst in the MO degradation was based on TiO₂-nanotubes sensitized with the dye protoporfirin (ZnP). Selected catalysts were also tested in the phenol and MO photodegradation under visible light and it was observed that these samples are also active under this radiation.
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15
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Tang CH, Hsiao PH, Chen CY. Efficient Photocatalysts Made by Uniform Decoration of Cu 2O Nanoparticles on Si Nanowire Arrays with Low Visible Reflectivity. NANOSCALE RESEARCH LETTERS 2018; 13:312. [PMID: 30288628 PMCID: PMC6172162 DOI: 10.1186/s11671-018-2735-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/22/2018] [Accepted: 09/26/2018] [Indexed: 06/08/2023]
Abstract
Highly uniformed decorations of Cu2O nanoparticles on the sidewalls of silicon nanowires (SiNWs) with high aspect ratio were prepared through a two-step electroless deposition at room temperature. Morphology evolutions and photocatalytic performance of SiNWs decorated with aggregated and dispersed Cu2O nanoparticles were unveiled, and the correlated photodegradation kinetics was identified. In comparison with the conventional direct loadings where the aggregated Cu2O/SiNW structures were created, the uniform incorporation of Cu2O with SiNWs exhibited more than three and nine times of improved photodegradation efficiency than the aggregated-Cu2O/SiNWs and sole SiNWs, respectively.
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Affiliation(s)
- Chien-Hsin Tang
- Department of Materials Science and Engineering, National Cheng Kung University, Tainan, 70101, Taiwan
| | - Po-Hsuan Hsiao
- Department of Materials Science and Engineering, National Cheng Kung University, Tainan, 70101, Taiwan
| | - Chia-Yun Chen
- Department of Materials Science and Engineering, National Cheng Kung University, Tainan, 70101, Taiwan.
- Hierarchical Green-Energy Materials (Hi-GEM) Research Center, National Cheng Kung University, Tainan, 70101, Taiwan.
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