51
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Geetha D, Kavitha S, Ramesh PS. A novel bio-degradable polymer stabilized Ag/TiO2 nanocomposites and their catalytic activity on reduction of methylene blue under natural sun light. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2015; 121:126-34. [PMID: 25976106 DOI: 10.1016/j.ecoenv.2015.04.042] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2014] [Revised: 04/21/2015] [Accepted: 04/27/2015] [Indexed: 05/09/2023]
Abstract
In the present work we defined a novel method of TiO2 doped silver nanocomposite synthesis and stabilization using bio-degradable polymers viz., chitosan (Cts) and polyethylene glycol (PEG). These polymers are used as reducing agents. The instant formation of AgNPs was analyzed by visual observation and UV-visible spectrophotometer. TiO2 nanoparticles doped at different concentrations viz., 0.03, 0.06 and 0.09mM on PEG/Cts stabilized silver (0.04wt%) were successfully synthesized. This study presents a simple route for the in situ synthesis of both metal and polymer confined within the nanomaterial, producing ternary hybrid inorganic-organic nanomaterials. The results reveal that they have higher photocatalytic efficiencies under natural sun light. The synthesized TiO2 doped Ag nanocomposites (NCs) were characterized by SEM/EDS, TEM, XRD, FTIR and DLS with zeta potential. The stability of Ag/TiO2 nanocomposite is due to the high negative values of zeta potential and capping of constituents present in the biodegradable polymer which is evident from zeta potential and FT-IR studies. The XRD and EDS pattern of synthesized Ag/TiO2 NCs showed their crystalline structure, with face centered cubic geometry oriented in (111) plane. AFM and DLS studies revealed that the diameter of stable Ag/TiO2 NCs was approximately 35nm. Moreover the catalytic activity of synthesize Ag/TiO2 NCs in the reduction of methylene blue was studied by UV-visible spectrophotometer. The synthesized Ag/TiO2 NCs are observed to have a good catalytic activity on the reduction of methylene blue by bio-degradable which is confirmed by the decrease in absorbance maximum value of methylene blue with respect to time using UV-vis spectrophotometer. The significant enhancement in the photocatalytic activity of Ag/TiO2 nanocomposites under sun light irradiation can be ascribed to the effect of noble metal Ag by acting as electron traps in TiO2 band gap.
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Affiliation(s)
- D Geetha
- Department of Physics, Annamalai University, Annamalai Nagar 608002, Tamil Nadu, India.
| | - S Kavitha
- Department of Physics, Annamalai University, Annamalai Nagar 608002, Tamil Nadu, India
| | - P S Ramesh
- Physics Wing DDE, Annamalai University, Annamalai Nagar 608002, Tamil Nadu, India
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52
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Xu D, Diao P, Jin T, Wu Q, Liu X, Guo X, Gong H, Li F, Xiang M, Ronghai Y. Iridium Oxide Nanoparticles and Iridium/Iridium Oxide Nanocomposites: Photochemical Fabrication and Application in Catalytic Reduction of 4-Nitrophenol. ACS APPLIED MATERIALS & INTERFACES 2015; 7:16738-49. [PMID: 26158693 DOI: 10.1021/acsami.5b04504] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Hydrous iridium oxide (IrOx) nanoparticles (NPs) with an average diameter of 1.7 ± 0.3 nm were prepared via photochemical hydrolysis of iridium chloride in alkaline medium at room temperature. The photoinduced hydrolysis was monitored by time-dependent ultraviolet-visible (UV-vis) spectroscopy, and the effects of the incident wavelength and irradiation time on the production of IrOx NPs were systematically investigated. It was found that UV-vis irradiation is crucial for the generation of IrOx NPs during the hydrolysis of IrCl3, and once the irradiation was turned off, the hydrolysis reaction stopped immediately. The production rate of IrOx NPs greatly depended on the incident wavelength. There is a critical wavelength of 500 nm for the hydrolysis reaction, and IrOx NPs can only be produced under the illumination with an incident wavelength shorter than 500 nm. Moreover, the shorter the incident wavelength, the faster the growth rate of IrOx NPs. The obtained IrOx NPs were highly stable during two months of storage at 4 °C. The Ir/IrOx nanocomposites were prepared by surface reduction of IrOx NPs with NaBH4. The microstructure of the Ir/IrOx composite was characterized by transmission electron microscopy (TEM), and the presence of zero-valence Ir was confirmed by the X-ray diffraction (XRD) result. The Ir/IrOx nanocomposite exhibited good catalytic activity and high recycling stability toward the reduction of 4-nitrophenol. The catalytic activity per unit surface area of the Ir/IrOx composite catalyst was increased by a factor of 15 compared to that of pure Ir catalyst. The presence of the Ir/IrOx interfaces in the composite catalyst is believed to be responsible for the high activity.
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Affiliation(s)
- Di Xu
- †School of Materials Science and Engineering, Beihang University, Xueyuan Road No. 37, Haidian District, Beijing 100191, PR China
| | - Peng Diao
- †School of Materials Science and Engineering, Beihang University, Xueyuan Road No. 37, Haidian District, Beijing 100191, PR China
| | - Tao Jin
- †School of Materials Science and Engineering, Beihang University, Xueyuan Road No. 37, Haidian District, Beijing 100191, PR China
| | - Qingyong Wu
- †School of Materials Science and Engineering, Beihang University, Xueyuan Road No. 37, Haidian District, Beijing 100191, PR China
| | - Xiaofang Liu
- †School of Materials Science and Engineering, Beihang University, Xueyuan Road No. 37, Haidian District, Beijing 100191, PR China
| | - Xin Guo
- †School of Materials Science and Engineering, Beihang University, Xueyuan Road No. 37, Haidian District, Beijing 100191, PR China
| | - Hongyu Gong
- ‡College of Environmental and Energy Engineering, Beijing University of Technology, Beijing 100124, PR China
| | - Fan Li
- ‡College of Environmental and Energy Engineering, Beijing University of Technology, Beijing 100124, PR China
| | - Min Xiang
- †School of Materials Science and Engineering, Beihang University, Xueyuan Road No. 37, Haidian District, Beijing 100191, PR China
| | - Yu Ronghai
- †School of Materials Science and Engineering, Beihang University, Xueyuan Road No. 37, Haidian District, Beijing 100191, PR China
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53
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Aditya T, Pal A, Pal T. Nitroarene reduction: a trusted model reaction to test nanoparticle catalysts. Chem Commun (Camb) 2015; 51:9410-31. [PMID: 25872865 DOI: 10.1039/c5cc01131k] [Citation(s) in RCA: 409] [Impact Index Per Article: 45.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Nitrophenol reduction to aminophenol with a reducing agent is conveniently carried out in aqueous medium mainly with a metal or metal oxide catalyst. This reduction is presently considered as a benchmark reaction to test a catalyst nanoparticle. Thousands of original reports have enriched this field of nanoparticle catalyzed reaction. Synthesis of different metal and metal oxide nanoparticles and their composites along with their role as catalysts for nitrophenol reduction with varying reducing agents have been elucidated here. The progress of the reaction is conveniently monitored by UV-visible spectrophotometry and hence it becomes a universally accepted model reaction. In this review we have discussed the reaction kinetics considering its elegance and importance enlightening the long known Langmuir-Hinshelwood mechanism and Eley-Rideal mechanism at length, along with a few other mechanisms recently reported. A brief description of the synthetic procedures of various nanoparticles and their respective catalytic behaviour towards nitroarene reduction has also been accounted here.
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Affiliation(s)
- Teresa Aditya
- Department of Chemistry, Indian Institute of Technology, Kharagpur 721302, India.
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54
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Dalui A, Thupakula U, Khan AH, Ghosh T, Satpati B, Acharya S. Mechanism of versatile catalytic activities of quaternary CuZnFeS nanocrystals designed by a rapid synthesis route. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2015; 11:1829-1839. [PMID: 25504671 DOI: 10.1002/smll.201402837] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/22/2014] [Indexed: 06/04/2023]
Abstract
Quaternary alloyed nanocrystals (NCs) composed of earth abundant, environment friendly elements are of interest for energy-harvesting applications. These complex NCs are useful as catalysts for the degradation of multiple refractory organic pollutants as well as nitro-organic reduction at a rapid rate. Here, a remarkably fast (∼30 s) and facile synthesis of crystalline quaternary chalcopyrite copper-zinc-iron-sulfide (CZIS) NCs is reported. These NCs show excellent catalytic properties by degrading a number of refractory organic dyes and converting nitro-compounds at a rapid rate. The valence and conduction band information of the newly designed NCs are extracted using scanning tunneling spectroscopy and ultraviolet photoelectron spectroscopy, which reveal energy levels suitable for performing redox chemistry by generating reactive radicals establishing NCs as efficient catalyst with multiple uses. Rapid synthesis of high quality phase-controlled CZIS NCs with robust catalytic activities could be useful for organic waste treatment.
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Affiliation(s)
- Amit Dalui
- Centre for Advanced Materials, Indian Association for the Cultivation of Science, Jadavpur, Kolkata, 700032, India
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55
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Zhao P, Feng X, Huang D, Yang G, Astruc D. Basic concepts and recent advances in nitrophenol reduction by gold- and other transition metal nanoparticles. Coord Chem Rev 2015. [DOI: 10.1016/j.ccr.2015.01.002] [Citation(s) in RCA: 476] [Impact Index Per Article: 52.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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56
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Metal dependent catalytic hydrogenation of nitroarenes over water-soluble glutathione capped metal nanoparticles. J Colloid Interface Sci 2015; 441:25-9. [DOI: 10.1016/j.jcis.2014.11.030] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2014] [Revised: 11/10/2014] [Accepted: 11/10/2014] [Indexed: 11/20/2022]
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57
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Bindhu MR, Umadevi M. Antibacterial and catalytic activities of green synthesized silver nanoparticles. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2015; 135:373-8. [PMID: 25093965 DOI: 10.1016/j.saa.2014.07.045] [Citation(s) in RCA: 151] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2014] [Revised: 07/01/2014] [Accepted: 07/18/2014] [Indexed: 05/22/2023]
Abstract
The aqueous beetroot extract was used as reducing agent for silver nanoparticles synthesis. The synthesized nanoparticles were characterized using UV-visible spectroscopy, X-ray diffraction (XRD) and transmission electron microscopy (TEM). The surface plasmon resonance peak of synthesized nanoparticles was observed at 438 nm. As the concentration of beetroot extract increases, absorption spectra shows blue shift with decreasing particle size. The prepared silver nanoparticles were well dispersed, spherical in shape with the average particle size of 15 nm. The prepared silver nanoparticles are effective in inhibiting the growth of both gram positive and gram negative bacteria. The prepared silver nanoparticles reveal faster catalytic activity. This natural method for synthesis of silver nanoparticles offers a valuable contribution in the area of green synthesis and nanotechnology avoiding the presence of hazardous and toxic solvents and waste.
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Affiliation(s)
- M R Bindhu
- Department of Physics, Mother Teresa Women's University, Kodaikanal 624101, Tamil Nadu, India
| | - M Umadevi
- Department of Physics, Mother Teresa Women's University, Kodaikanal 624101, Tamil Nadu, India.
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58
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Narayanan RK, Devaki SJ. Brawny Silver-Hydrogel Based Nanocatalyst for Reduction of Nitrophenols: Studies on Kinetics and Mechanism. Ind Eng Chem Res 2015. [DOI: 10.1021/ie5038352] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Rohini Kuttiplavil Narayanan
- CSIR-National Institute for Interdisciplinary Science and Technology (CSIR-NIIST), Thiruvananthapuram 695
019, India
| | - Sudha Janardhanan Devaki
- CSIR-National Institute for Interdisciplinary Science and Technology (CSIR-NIIST), Thiruvananthapuram 695
019, India
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59
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Xun S, Zhu W, Zheng D, Li H, Jiang W, Zhang M, Qin Y, Zhao Z, Li H. Supported ionic liquid [Bmim]FeCl4/Am TiO2 as an efficient catalyst for the catalytic oxidative desulfurization of fuels. RSC Adv 2015. [DOI: 10.1039/c5ra00999e] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Supported ionic liquid catalyst [Bmim]FeCl4/Am TiO2 was synthesized and showed excellent desulfurization efficiency and reuseable performance in the ECODS system.
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Affiliation(s)
- Suhang Xun
- School of Chemistry and Chemical Engineering
- Jiangsu University
- Zhenjiang
- P. R. China
| | - Wenshuai Zhu
- School of Chemistry and Chemical Engineering
- Jiangsu University
- Zhenjiang
- P. R. China
| | - Dan Zheng
- School of Chemistry and Chemical Engineering
- Jiangsu University
- Zhenjiang
- P. R. China
| | - Hongping Li
- School of Chemistry and Chemical Engineering
- Jiangsu University
- Zhenjiang
- P. R. China
| | - Wei Jiang
- Institute for Energy Research
- Jiangsu University
- Zhenjiang 212013
- P. R. China
| | - Ming Zhang
- Institute for Energy Research
- Jiangsu University
- Zhenjiang 212013
- P. R. China
| | - Yuejiao Qin
- School of Chemistry and Chemical Engineering
- Jiangsu University
- Zhenjiang
- P. R. China
| | - Zhen Zhao
- State Key Laboratory of Heavy Oil Processing
- Faculty of Science
- China University of Petroleum
- Beijing 102249
- P. R. China
| | - Huaming Li
- Institute for Energy Research
- Jiangsu University
- Zhenjiang 212013
- P. R. China
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60
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Kannan A, Rajakumar P. Synthesis and catalytic application of glycodendrimers decorated with gold nanoparticles – reduction of 4-nitrophenol. RSC Adv 2015. [DOI: 10.1039/c5ra06375b] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Au–DSNPs and Au–DENPs with an average diameter of 7.2 and 4.0 nm have been synthesized and proved to be good catalysts for the reduction of 4-nitrophenol.
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Affiliation(s)
- Ayyavoo Kannan
- Department of Organic Chemistry
- University of Madras
- Guindy Campus
- Chennai 600025
- India
| | - Perumal Rajakumar
- Department of Organic Chemistry
- University of Madras
- Guindy Campus
- Chennai 600025
- India
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61
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Zhao Z, Wang Y, Xu J, Wang Y. Mesoporous Ag/TiO2nanocomposites with greatly enhanced photocatalytic performance towards degradation of methyl orange under visible light. RSC Adv 2015. [DOI: 10.1039/c5ra12065a] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Mesoporous Ag/TiO2nanocomposites fabricated by dealloying/calcination show superior photocatalytic performance under visible light as well as UV irradiation.
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Affiliation(s)
- Zhengfeng Zhao
- School of Materials Science and Engineering
- University of Jinan
- Jinan 250022
- PR China
- Shandong Provincial Key Laboratory of Preparation & Measurement of Building Materials
| | - Yingzi Wang
- School of Materials Science and Engineering
- University of Jinan
- Jinan 250022
- PR China
| | - Jing Xu
- School of Materials Science and Engineering
- University of Jinan
- Jinan 250022
- PR China
| | - Yan Wang
- School of Materials Science and Engineering
- University of Jinan
- Jinan 250022
- PR China
- Shandong Provincial Key Laboratory of Preparation & Measurement of Building Materials
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62
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Chen JY, Sun L, Jiang W, Lynch VM. Antimicrobial regenerated cellulose/nano-silver fiber without leaching. J BIOACT COMPAT POL 2014. [DOI: 10.1177/0883911514556960] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The formation of antimicrobial regenerated cellulose fibers using an ionic liquid solvent, 1-butyl-3-methylimidazolium chloride, and silver nanoparticles was studied. The cellulose preparation and dispersion efficiency of the silver nanoparticles in the solvent were evaluated via scanning electron microscope and transmission electron microscopy in terms of different processing conditions. The influence of silver nanoparticles on regenerated cellulose fiber crystallization and strength was examined using a wide angle X-ray diffractometry and tensiometry, respectively. The bioactive efficacy of the cellulose/nano-silver fiber was tested in accordance with the standard method of ASTM E 2149-10. The cellulose/nano-silver fibers were bioactive and killed Escherichia coli almost completely without any leaching problems. The addition of nano-silver significantly increased the cellulose fiber tensile strength and modulus with an insignificant reduction in fiber elongation, and a slower thermal decomposition rate, evidenced by increased fiber crystallinity. Higher processing temperatures improved the nano-silver dispersion efficiency. The final nano-silver suspension in the regenerated cellulose matrix was composed of scattered clusters with an average size of 700 nm and a distribution density of 14,098 mm−2.
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Affiliation(s)
- Jonathan Y Chen
- School of Human Ecology, The University of Texas at Austin, Austin, TX, USA
| | - Liangfeng Sun
- School of Human Ecology, The University of Texas at Austin, Austin, TX, USA
| | - Wei Jiang
- School of Human Ecology, The University of Texas at Austin, Austin, TX, USA
| | - Vincent M Lynch
- Department of Chemistry, The University of Texas at Austin, Austin, TX, USA
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63
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Wu J, Tan LH, Hwang K, Xing H, Wu P, Li W, Lu Y. DNA Sequence-Dependent Morphological Evolution of Silver Nanoparticles and Their Optical and Hybridization Properties. J Am Chem Soc 2014; 136:15195-202. [DOI: 10.1021/ja506150s] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Affiliation(s)
- Jiangjiexing Wu
- Collaborative Innovation Center
of Chemical Science and
Chemical Engineering (Tianjin) and Key Laboratory for Green Chemical Technology MOE, Tianjin University, Tianjin 300072, People’s Republic of China
- Department
of Chemistry, University of Illinois at Urbana−Champaign, Urbana, Illinois 61801, United States
| | - Li Huey Tan
- Department
of Chemistry, University of Illinois at Urbana−Champaign, Urbana, Illinois 61801, United States
| | - Kevin Hwang
- Department
of Chemistry, University of Illinois at Urbana−Champaign, Urbana, Illinois 61801, United States
| | - Hang Xing
- Department
of Chemistry, University of Illinois at Urbana−Champaign, Urbana, Illinois 61801, United States
| | - Peiwen Wu
- Department
of Biochemistry, University of Illinois at Urbana−Champaign, Urbana, Illinois 61801, United States
| | - Wei Li
- Collaborative Innovation Center
of Chemical Science and
Chemical Engineering (Tianjin) and Key Laboratory for Green Chemical Technology MOE, Tianjin University, Tianjin 300072, People’s Republic of China
| | - Yi Lu
- Department
of Chemistry, University of Illinois at Urbana−Champaign, Urbana, Illinois 61801, United States
- Department
of Biochemistry, University of Illinois at Urbana−Champaign, Urbana, Illinois 61801, United States
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64
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Wang P, Du M, Zhang M, Zhu H, Bao S. The preparation of tubular heterostructures based on titanium dioxide and silica nanotubes and their photocatalytic activity. Dalton Trans 2014; 43:1846-53. [PMID: 24257115 DOI: 10.1039/c3dt51959g] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Tubular heterostructures based on titanium dioxide (TiO2) and silica nanotubes (SNTs) with high photocatalytic activity have been successfully obtained by a simple combination of an electrospinning technique and a solvothermal process. The as-prepared products were characterized by field-emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), and N2 absorption-desorption experiments. The results confirmed that SNTs with high specific surface area were obtained by efficiently controlling the phase separation and solvent evaporation during the process of electrospinning and calcination, and TiO2 was successfully grown on the SNT substrates. The obtained titanium dioxide/silica nanotubes (TiO2/SNTs) heterostructures showed high photocatalytic activities to degrade Rhodamine 6G because of the formation of heterostructures, which might improve the separation of photogenerated electrons and holes. Furthermore, the TiO2/SNTs heterostructures could be easily recycled without an evident decrease in photocatalytic activity.
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Affiliation(s)
- Pan Wang
- Zhejiang Sci-Tech University, Hangzhou, China.
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65
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Yang C, Jung S, Yi H. A biofabrication approach for controlled synthesis of silver nanoparticles with high catalytic and antibacterial activities. Biochem Eng J 2014. [DOI: 10.1016/j.bej.2013.12.008] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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66
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Park HH, Woo K, Ahn JP. Core-shell bimetallic nanoparticles robustly fixed on the outermost surface of magnetic silica microspheres. Sci Rep 2014; 3:1497. [PMID: 23511209 PMCID: PMC3603323 DOI: 10.1038/srep01497] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2012] [Accepted: 03/04/2013] [Indexed: 11/09/2022] Open
Abstract
The major challenges in practically utilising the immense potential benefits of nanomaterials are controlling aggregation, recycling the nanomaterials, and fabricating well-defined nanoparticulate materials using innovative methods. We present a novel innovative synthetic strategy for core–shell bimetallic nanoparticles that are well-defined, ligand-free, and robustly fixed on the outermost surface of recyclable magnetic silica microspheres. The strategy includes seeding, coalescing the seeds to cores, and then growing shells from the cores on aminopropyl-functionalised silica microspheres so that the cores and aminopropyl moieties are robustly embedded in the shell materials. The representative Au–Ag bimetallic nanoparticles fixed on the microsphere showed excellent catalytic performance that remained consistent during repeated catalytic cycles.
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Affiliation(s)
- Hye Hun Park
- Molecular Recognition Research Center, Korea Institute of Science and Technology, P. O. Box 131, Cheongryang, Seoul 130-650, Korea
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67
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Borase HP, Patil CD, Salunkhe RB, Suryawanshi RK, Salunke BK, Patil SV. Catalytic and synergistic antibacterial potential of green synthesized silver nanoparticles: Their ecotoxicological evaluation on Poecillia reticulata. Biotechnol Appl Biochem 2014; 61:385-94. [PMID: 24329901 DOI: 10.1002/bab.1189] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2013] [Accepted: 12/02/2013] [Indexed: 11/11/2022]
Abstract
In the present study, stable silver nanoparticles (AgNPs) were fabricated at a rapid rate from leaf extract of medicinally important plant Alstonia macrophylla. Biosynthesized AgNPs are of spherical shape and narrow size (70 nm), exhibiting a surface plasmon resonance peak at 435 nm, and a zeta potential of -30.8 mV and have a crystalline nature. A diverse biochemical consortium of protein, terpenoids, phenolics, and flavonoids in leaf extract of A. macrophylla was found to be responsible for AgNP synthesis as evidenced from qualitative-quantitative chemical analysis and Fourier transform infrared spectroscopy studies. Nitroaromatic compounds are anthropogenic pollutants with long-lasting environmental persistence and are needed to transform into less toxic derivatives. 4-Nitrophenol and p-nitroaniline were reduced to less hazardous and commercially useful 4-aminophenol and p-phenylenediamine by phytosynthesized AgNPs. Rate constants of 0.052 and 0.040 Min(-1) were calculated for 4-nitrophenol and p-nitroaniline reduction, respectively. Thin-layer chromatography also confirms the reduction of these nitroaromatic compounds. Combinational studies could be one of the strategies to overcome microbial resistance to antibiotics. In synergistic antibacterial assay, the highest increase in a fold area of 3.84 was reported against Staphylococcus aureus using a combination of AgNPs with penicillin. Biosynthesized AgNPs were found to be less toxic (LC50 = 9.13 ppm) than chemically synthesized AgNPs having a LC50 value of 2.86 ppm against nontarget fish Poecillia reticulata. Our green nanosynthesis method offers a faster rate of formation of stable AgNPs having antibacterial and catalytic potential with lower environmental toxicity.
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Affiliation(s)
- Hemant P Borase
- School of Life Sciences, North Maharashtra University, Jalgaon, India
| | | | - Rahul B Salunkhe
- School of Life Sciences, North Maharashtra University, Jalgaon, India
| | | | | | - Satish V Patil
- School of Life Sciences, North Maharashtra University, Jalgaon, India.,North Maharashtra Microbial Culture Collection Centre, North Maharashtra University, Jalgaon, India
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68
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Ciganda R, Li N, Deraedt C, Gatard S, Zhao P, Salmon L, Hernández R, Ruiz J, Astruc D. Gold nanoparticles as electron reservoir redox catalysts for 4-nitrophenol reduction: a strong stereoelectronic ligand influence. Chem Commun (Camb) 2014; 50:10126-9. [DOI: 10.1039/c4cc04454a] [Citation(s) in RCA: 94] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Gold nanoparticle-catalyzed p-nitrophenol reduction by NaBH4 is shown to strongly depend on the stereoelectronic ligand properties involving surface electron reservoirs.
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Affiliation(s)
- Roberto Ciganda
- Univ. Bordeaux
- ISM
- UMR 5515
- 33405 Talence Cedex, France
- Facultad de Química de San Sebastian
| | - Na Li
- Univ. Bordeaux
- ISM
- UMR 5515
- 33405 Talence Cedex, France
| | | | | | - Pengxiang Zhao
- Univ. Bordeaux
- ISM
- UMR 5515
- 33405 Talence Cedex, France
- Science and Technology on Surface Physics and Chemistry Laboratory
| | | | - Ricardo Hernández
- Facultad de Química de San Sebastian
- Universidad del País Vasco
- 20080 San Sebastian, Spain
| | - Jaime Ruiz
- Univ. Bordeaux
- ISM
- UMR 5515
- 33405 Talence Cedex, France
| | - Didier Astruc
- Univ. Bordeaux
- ISM
- UMR 5515
- 33405 Talence Cedex, France
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69
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Li J, Liang J, Wu W, Zhang S, Zhang K, Zhou H. AuCl4−-responsive self-assembly of ionic liquid block copolymers for obtaining composite gold nanoparticles and polymeric micelles with controlled morphologies. NEW J CHEM 2014. [DOI: 10.1039/c4nj00128a] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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70
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Li M, Chen G. Revisiting catalytic model reaction p-nitrophenol/NaBH4 using metallic nanoparticles coated on polymeric spheres. NANOSCALE 2013; 5:11919-27. [PMID: 24129942 DOI: 10.1039/c3nr03521b] [Citation(s) in RCA: 112] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
The early reported pseudo-first-order reaction kinetics of the polymer-supported metallic nanocatalysts for the model reaction of p-nitrophenol (p-NP)/NaBH4 were probably oversimplified. Here a detailed study of p-NP reduction by NaBH4 in the presence of the raspberry-like poly(allylamine hydrochloride)-modified polymer poly(glycidyl methacrylate) composite sub-microspheres with tunable gold nanoparticles (PGMA@PAH@AuNPs) was presented. Effects of polyelectrolyte concentration, the ratio of polymer spheres to gold nanoparticles, and the solution pH value for composite synthesis on the induction period, reaction time, average reaction rate and average turnover frequency were systematically investigated. Experimental results in all cases of our study revealed an n(th) order (n > 1) of the p-NP/NaBH4 catalytic reaction by the prepared polymer composite particles. The apparent order of reaction, n, is dependent on the total surface area of the coated gold nanoparticles on the polymer spheres, which can be closely correlated with the tunable gold nanoparticle surface coverage. The mechanism of the observed catalytic activity enhancement was proposed based on active epoxy groups of the polymer spheres and a large adsorption of p-nitrophenolate anions onto the positively-charged spheres.
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Affiliation(s)
- Maolin Li
- Chemistry Department, St John's University, Queens, New York 11439, USA.
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71
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Li J, Li W, Qiang W, Wang X, Li H, Xu D. A non-aggregation colorimetric assay for thrombin based on catalytic properties of silver nanoparticles. Anal Chim Acta 2013; 807:120-5. [PMID: 24356228 DOI: 10.1016/j.aca.2013.11.011] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2013] [Revised: 11/01/2013] [Accepted: 11/07/2013] [Indexed: 10/26/2022]
Abstract
In this paper, we developed a simple and rapid colorimetric assay for protein detection based on the reduction of dye molecules catalyzed by silver nanoparticles (AgNPs). Aptamer-modified magnetic particles and aptamer-functionalized AgNPs were employed as capture and detection probes, respectively. Introduction of thrombin as target protein could form a sandwich-type complex involving catalytically active AgNPs, whose catalytic activity was monitored on the catalytic reduction of rhodamine B (RhB) by sodium borohydride (NaBH4). The amount of immobilized AgNPs on the complex increased along with the increase of the thrombin concentration, thus the detection of thrombin was achieved via recording the decrease in absorbance corresponding to RhB. This method has adopted several advantages from the key factors involved, i.e., the sandwich binding of affinity aptamers contributed to the increased specificity; magnetic particles could result in rapid capture and separation processes; the conjugation of AgNPs would lead to a clear visual detection. It allows for the detection limit of thrombin down to picomolar level by the naked eye, with remarkable selectivity over other proteins. Moreover, it is possible to apply this method to the other targets with two binding sites as well.
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Affiliation(s)
- Jie Li
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, China
| | - Wei Li
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, China
| | - Weibing Qiang
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, China
| | - Xi Wang
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, China
| | - Hui Li
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, China
| | - Danke Xu
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, China.
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72
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Antonels NC, Meijboom R. Preparation of well-defined dendrimer encapsulated ruthenium nanoparticles and their evaluation in the reduction of 4-nitrophenol according to the Langmuir-Hinshelwood approach. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2013; 29:13433-42. [PMID: 24087990 DOI: 10.1021/la402885k] [Citation(s) in RCA: 97] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
This study discusses the preparation of various sized dendrimer encapsulated ruthenium nanoparticles (RuDEN) with the use of the generation 4 (G4), generation 5 (G5), and generation 6 (G6) hydroxyl-terminated poly(amidoamine) (PAMAM-OH) dendrimers as templating agents. The size of the nanoparticles ranges from 1.1 to 2.2 nm. These catalysts were fully characterized using UV/vis spectrophotometry, infrared (IR) spectroscopy, and transmission electron microscopy (TEM). The RuDEN catalysts were evaluated in the reduction of 4-nitrophenol (4NP) in the presence of sodium borohydride (BH4(-)) for various concentrations of either. The kinetic data obtained were modeled to the Langmuir-Hinshelwood equation. The model allows the relation of the apparent rate constant to the total surface area S of the nanoparticle, the kinetic constant k which is related to the rate-determining step, and the adsorption constants K(4NP) and K(BH4) for 4NP and borohydride, respectively. These parameters were calculated for each of the RuDENs, proving the Langmuir-Hinshelwood model to be suitable for the kinetic evaluation of RuDENs in the catalytic reduction of 4NP.
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Affiliation(s)
- Nathan Charles Antonels
- Research Centre for Synthesis and Catalysis, Department of Chemistry, University of Johannesburg , P.O. Box 524, Auckland Park 2006, South Africa
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73
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Lu Q, Lu Z, Lu Y, Lv L, Ning Y, Yu H, Hou Y, Yin Y. Photocatalytic synthesis and photovoltaic application of Ag-TiO2 nanorod composites. NANO LETTERS 2013; 13:5698-5702. [PMID: 24164212 DOI: 10.1021/nl403430x] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
A photocatalytic strategy has been developed to synthesize colloidal Ag-TiO2 nanorod composites in which each TiO2 nanorod contains a single Ag nanoparticle on its surface. In this rational synthesis, photoexcitation of TiO2 nanorods under UV illumination produces electrons that reduce Ag(I) precursor and deposit multiple small Ag nanoparticles on the surface of TiO2 nanorods. Prolonged UV irradiation induces an interesting ripening process, which dissolves the smaller nanoparticles by photogenerated oxidative species and then redeposits Ag onto one larger and more stable particle attached to each TiO2 nanorod through the reduction of photoexcited electrons. The size of the Ag nanoparticles can be precisely controlled by varying the irradiation time and the amount of alcohol additive. The Ag-TiO2 nanorod composites were used as electron transport layers in the fabrication of organic solar cells and showed notable enhancement in power conversion efficiency (6.92%) than pure TiO2 nanorods (5.81%), as well as higher external quantum efficiency due to improved charge separation and transfer by the presence of Ag nanoparticles.
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Affiliation(s)
- Qipeng Lu
- Department of Chemistry, University of California , Riverside, California 92521, United States
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74
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Edison TJI, Sethuraman MG. Biogenic robust synthesis of silver nanoparticles using Punica granatum peel and its application as a green catalyst for the reduction of an anthropogenic pollutant 4-nitrophenol. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2013; 104:262-264. [PMID: 23274256 DOI: 10.1016/j.saa.2012.11.084] [Citation(s) in RCA: 79] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2012] [Revised: 11/19/2012] [Accepted: 11/27/2012] [Indexed: 06/01/2023]
Abstract
A robust synthesis of silver nanoparticles (AgNPs) using the peel extract of Punica granatum is reported in this article. The formation of AgNPs was confirmed by the appearance of brownish yellow color and the Surface Plasmon Resonance (SPR) peak at 432 nm. The biogenic AgNPs were found to have the size approximately 30 nm with distorted spherical shape. The high negative zeta potential values of AgNPs revealed their high stability which could be attributed to the capping of AgNPs by the phytoconstituents of the Punica granatum peel. The biogenic AgNPs were also found to function as an effective green catalyst in the reduction of anthropogenic pollutant viz., 4-nitrophenol (4-NP) by solid sodium borohydride, which was evident from the instantaneous color change of bright yellow (400 nm) to colorless (294 nm) solution, after the addition of AgNPs. The catalytic action of biogenic AgNPs in the reduction of 4-NP could be explained on the basis of Langmuir-Hinshelwood model.
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Affiliation(s)
- T Jebakumar Immanuel Edison
- Department of Chemistry, Gandhigram Rural Institute - Deemed University, Gandhigram 624 302, Dindigul District, Tamil Nadu, India
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75
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Liu W, Shi M, Lang X, Zhao D, Chu Y, Ma C. Highly dispersed nanocrystallines WC supported on microwave exfoliated RGO by ionic liquid and its catalytic performance in electroreduction of nitrobenzene. Catal Today 2013. [DOI: 10.1016/j.cattod.2012.08.017] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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76
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Jiang B, Hou Z, Tian C, Zhou W, Zhang X, Wu A, Tian G, Pan K, Ren Z, Fu H. A facile and green synthesis route towards two-dimensional TiO2@Ag heterojunction structure with enhanced visible light photocatalytic activity. CrystEngComm 2013. [DOI: 10.1039/c3ce40510a] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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77
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Yang MQ, Pan X, Zhang N, Xu YJ. A facile one-step way to anchor noble metal (Au, Ag, Pd) nanoparticles on a reduced graphene oxide mat with catalytic activity for selective reduction of nitroaromatic compounds. CrystEngComm 2013. [DOI: 10.1039/c3ce40694f] [Citation(s) in RCA: 151] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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78
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Nigra MM, Ha JM, Katz A. Identification of site requirements for reduction of 4-nitrophenol using gold nanoparticle catalysts. Catal Sci Technol 2013. [DOI: 10.1039/c3cy00298e] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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79
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Gan Z, Zhao A, Zhang M, Tao W, Guo H, Gao Q, Mao R, Liu E. Controlled synthesis of Au-loaded Fe3O4@C composite microspheres with superior SERS detection and catalytic degradation abilities for organic dyes. Dalton Trans 2013; 42:8597-605. [DOI: 10.1039/c3dt50341k] [Citation(s) in RCA: 98] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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80
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Ma K, Shao Y, Cui Q, Wu F, Xu S, Liu G. Base-stacking-determined fluorescence emission of DNA abasic site-templated silver nanoclusters. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2012; 28:15313-15322. [PMID: 22881065 DOI: 10.1021/la301957m] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
DNA-templated silver nanoclusters (Ag NCs) are emerging sets of fluorophores that are widely applicable because of high brightness, good photostability, and visible to near-infrared emissions tunable using the DNA sequence and length to change the NC size. We find that fluorescent Ag NCs can be size-selectively grown at DNA abasic sites (AP site) using a constrained duplex environment opposed by a cytosine and flanked by two guanines. The size of the AP site-grown Ag NCs is not affected by the increasing Ag(+) concentration. A Job's plot analysis shows that Ag(2) NCs are the species responsible for the observed emissions. Although varying the DNA sequence one base away from the AP site (i.e., the Ag NC growth site) does not alter the size of the fluorescent Ag NCs, the emissions of the formed Ag NCs are still gradually red shifted as the sequence changes from thymine (T) to cytosine (C), adenine (A), and guanine (G). Furthermore, this emission shift is strongly dependent on the base-stacking direction of the 3'-side sequence of the 5'-G stack exactly flanking the AP site, which exhibits a larger emission alteration than altering the 5'-side sequence of the 3'-G stack flanking the AP site on the other side of the site. The excited-state lifetimes of the Ag NCs are inversely proportional to the singlet energies (ΔE(0,0)) of the Ag NCs relative to their ground state and of the vertical ionization potentials of the guanines directly flanking the AP site as determined by the base stacking. All of these results support the conclusion that the Ag NC excited state becomes more stable by interacting with a guanine base because of the larger electronic dipole moment that can be modified by the stacked sequences. Additionally, the size of the formed Ag NCs seems to be dependent on the consecutive AP site number. Thus, the AP site design in this work provides an easy way to shed light on the role of DNA base stacking in the optical properties of Ag NCs.
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Affiliation(s)
- Kun Ma
- Zhejiang Key Laboratory for Reactive Chemistry on Solid Surfaces, Institute of Physical Chemistry, Zhejiang Normal University, Jinhua 321004, Zhejiang, People's Republic of China
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81
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Chi Y, Yuan Q, Li Y, Tu J, Zhao L, Li N, Li X. Synthesis of Fe3O4@SiO2–Ag magnetic nanocomposite based on small-sized and highly dispersed silver nanoparticles for catalytic reduction of 4-nitrophenol. J Colloid Interface Sci 2012; 383:96-102. [DOI: 10.1016/j.jcis.2012.06.027] [Citation(s) in RCA: 242] [Impact Index Per Article: 20.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2012] [Revised: 06/08/2012] [Accepted: 06/12/2012] [Indexed: 01/20/2023]
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82
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Synthesis of worm like silver nanoparticles in methyl cellulose polymeric matrix and its catalytic activity. Carbohydr Polym 2012; 89:830-5. [DOI: 10.1016/j.carbpol.2012.04.017] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2012] [Revised: 04/06/2012] [Accepted: 04/07/2012] [Indexed: 11/21/2022]
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83
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Zhang W, Tan F, Wang W, Qiu X, Qiao X, Chen J. Facile, template-free synthesis of silver nanodendrites with high catalytic activity for the reduction of p-nitrophenol. JOURNAL OF HAZARDOUS MATERIALS 2012; 217-218:36-42. [PMID: 22459973 DOI: 10.1016/j.jhazmat.2012.01.056] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2011] [Revised: 11/30/2011] [Accepted: 01/17/2012] [Indexed: 05/31/2023]
Abstract
Here we report a facile, surfactant-free and template-free synthesis process of highly uniform dendritic silver nanostructures with high catalytic activity for the reduction of p-nitrophenol. By controlling the concentration of AgNO(3) aqueous solution and the reaction time, various shapes of silver nanodendrites (SNDs) could be obtained easily. The effects of different parameters such as concentrations of the reagents and reaction time on the morphology and structure of as-prepared tree-like nanostructures have also been investigated by X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM). Also, the X-ray photoelectron spectroscopy (XPS) has been used to identify the oxidation state of SNDs. In addition, the catalytic activity of the as-prepared SNDs samples at 200 mM AgNO(3) aqueous solution was evaluated by a redox reaction of p-nitrophenol in the presence of an excess amount of NaBH(4). It was found that the highly symmetrical SNDs with roughly 60-120 nm in stem and branch diameter and 3-12 μm in length obtained after 120 s reaction time do have higher catalytic activity than other SNDs prepared at different reaction time, several times stronger catalytic activity in the sodium borohydride reduction of p-nitrophenol to p-aminophenol, compared to some other silver nanoparticles reported in literature. The crystallinity provided by X-ray diffraction (XRD) analysis indicates that the improvement of the crystallinity is also very crucial for SNDs' catalytic activities. The SNDs are very promising catalytic candidates for the reduction of p-nitrophenol because of easily simple preparation route and high catalytic activity.
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Affiliation(s)
- Wei Zhang
- State Key Laboratory of Plastic Forming Simulation and Die and Mold Technology, Huazhong University of Science and Technology, Wuhan, Hubei, People's Republic of China
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84
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Zhang Z, Shao C, Sun Y, Mu J, Zhang M, Zhang P, Guo Z, Liang P, Wang C, Liu Y. Tubular nanocomposite catalysts based on size-controlled and highly dispersed silver nanoparticles assembled on electrospun silicananotubes for catalytic reduction of 4-nitrophenol. ACTA ACUST UNITED AC 2012. [DOI: 10.1039/c1jm13421c] [Citation(s) in RCA: 235] [Impact Index Per Article: 19.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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85
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Ghosh S, Goudar VS, Padmalekha KG, Bhat SV, Indi SS, Vasan HN. ZnO/Ag nanohybrid: synthesis, characterization, synergistic antibacterial activity and its mechanism. RSC Adv 2012. [DOI: 10.1039/c1ra00815c] [Citation(s) in RCA: 148] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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86
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Zhang P, Shao C, Zhang Z, Zhang M, Mu J, Guo Z, Liu Y. In situ assembly of well-dispersed Ag nanoparticles (AgNPs) on electrospun carbon nanofibers (CNFs) for catalytic reduction of 4-nitrophenol. NANOSCALE 2011; 3:3357-63. [PMID: 21761072 DOI: 10.1039/c1nr10405e] [Citation(s) in RCA: 332] [Impact Index Per Article: 25.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
Carbon nanofibers/silver nanoparticles (CNFs/AgNPs) composite nanofibers were fabricated by two steps consisting of the preparation of the CNFs by electrospinning and the hydrothermal growth of the AgNPs on the CNFs. The as-prepared nanofibers were characterized by scanning electron microscopy, energy dispersive spectroscopy, transmission electron microscopy, X-ray diffraction, resonant Raman spectra, thermal gravimetric and differential thermal analysis, and X-ray photoelectron spectroscopy, respectively. The results indicated that not only were AgNPs (25-50 nm) successfully grown on the CNFs but also the AgNPs were distributed without aggregation on the CNFs. Further more, by adjusting the parameters in hydrothermal processing, the content of silver supported on the CNFs could be easily controlled. The catalytic activities of the CNFs/AgNPs composite nanofibers to the reduction of 4-nitrophenol (4-NP) with NaBH(4) were tracked by UV-visible spectroscopy. It was suggested that the CNFs/AgNPs composite nanofibers exhibited high catalytic activity in the reduction of 4-NP, which might be attributed to the high surface areas of AgNPs and synergistic effect on delivery of electrons between CNFs and AgNPs. And, the catalytic efficiency was enhanced with the increasing of the content of silver on the CNFs/AgNPs composite nanofibers. Notably, the CNFs/AgNPs composite nanofibers could be easily recycled due to their one-dimensional nanostructural property.
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Affiliation(s)
- Peng Zhang
- Center for Advanced Optoelectronic Functional Materials Research, Key Laboratory of UV Light-Emitting Materials and Technology of Ministry of Education, Northeast Normal University, 5268 Renmin Street, Changchun, 130024, People's Republic of China
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87
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Bootharaju MS, Pradeep T. Investigation into the reactivity of unsupported and supported Ag7 and Ag8 clusters with toxic metal ions. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2011; 27:8134-43. [PMID: 21667956 DOI: 10.1021/la200947c] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
We report the chemical interactions of unsupported and alumina-supported Ag(7) and Ag(8) clusters protected with MSA (mercaptosuccinic acid) with heavy metal ions Hg(II), Cd(II), and Pb(II) in water at different concentrations. The investigation was carried out to determine the feasibility of this interesting new class of materials called quantum clusters for water purification. These systems were studied using various spectroscopic and microscopic techniques such as ultraviolet-visible spectroscopy, Fourier transform infrared spectroscopy, X-ray diffraction, dynamic light scattering, zeta potential measurements, scanning electron microscopy, transmission electron microscopy, Raman spectroscopy, and photoluminescence spectroscopy and in detail by X-ray photoelectron spectroscopy. We observed that the metal ions interact with both the silver atoms of the clusters and the functional groups of the capping agent (MSA). The mercuric ions were reduced to metallic mercury by both supported and unsupported clusters, due to the feasibility of the redox reaction, whereas no reduction was observed for Cd(II) and Pb(II). As a result of the interaction, the luminescence of the cluster is lost which can be used to sense Hg(II). At lower concentrations, the metal ions were chemically bonded to the carboxylate groups of MSA. Absence of reduction of Hg(II) at lower concentration is due to the chemical affinity of the ligands and the lower silver content per cluster compared to the number of carboxylate groups.
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Affiliation(s)
- M S Bootharaju
- DST Unit of Nanoscience (DST UNS), Department of Chemistry, Indian Institute of Technology Madras, Chennai-600 036, India
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88
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Dinh CT, Nguyen TD, Kleitz F, Do TO. A new route to size and population control of silver clusters on colloidal TiO₂ nanocrystals. ACS APPLIED MATERIALS & INTERFACES 2011; 3:2228-2234. [PMID: 21675750 DOI: 10.1021/am200480b] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Formation of hybrid Ag-TiO(2) nanocrystals (NCs) in which Ag clusters are uniformly deposited on individual TiO(2) NC surface has been achieved by using hydrophobic surfactant-capped TiO(2) NCs in combination with a photodeposition technique. The population of Ag clusters on the individual TiO(2) NC surface can be controlled by the degree of hydrophobicity (e.g., the number of vacant sites) on the TiO(2) NC surface while their size may be altered simply by varying irradiation time. A reversible change in color of the resulting hybrid Ag-TiO(2) NCs is induced by alternating UV light and visible-light illumination; however, the size and population of Ag clusters on TiO(2) NCs are almost unchanged. Furthermore, these materials also exhibit much higher photocatalytic performance as compared to that of Ag supported on commercial TiO(2)-P25.
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Affiliation(s)
- Cao-Thang Dinh
- Department of Chemical Engineering, Centre de recherche sur les propriétés des interfaces et la catalyse (CERPIC), Laval University, Quebec G1 V 0A6, Canada
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89
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Wang S, Zhang M, Zhang W. Yolk−Shell Catalyst of Single Au Nanoparticle Encapsulated within Hollow Mesoporous Silica Microspheres. ACS Catal 2011. [DOI: 10.1021/cs1000762] [Citation(s) in RCA: 183] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Shengnan Wang
- Key Laboratory of Functional Polymer Materials of Ministry of Education, Institute of Polymer Chemistry, Nankai University, Tianjin 300071, China
| | - Minchao Zhang
- Key Laboratory of Functional Polymer Materials of Ministry of Education, Institute of Polymer Chemistry, Nankai University, Tianjin 300071, China
| | - Wangqing Zhang
- Key Laboratory of Functional Polymer Materials of Ministry of Education, Institute of Polymer Chemistry, Nankai University, Tianjin 300071, China
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90
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Shen J, Shi M, Yan B, Ma H, Li N, Ye M. One-pot hydrothermal synthesis of Ag-reduced graphene oxide composite with ionic liquid. ACTA ACUST UNITED AC 2011. [DOI: 10.1039/c1jm10671f] [Citation(s) in RCA: 133] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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91
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Hou Y, Li X, Zhao Q, Quan X, Chen G. TiO2 nanotube/Ag–AgBr three-component nanojunction for efficient photoconversion. ACTA ACUST UNITED AC 2011. [DOI: 10.1039/c1jm12788h] [Citation(s) in RCA: 86] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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92
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93
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Sasmal DK, Mojumdar SS, Adhikari A, Bhattacharyya K. Deuterium Isotope Effect on Femtosecond Solvation Dynamics in an Ionic Liquid Microemulsion: An Excitation Wavelength Dependence Study. J Phys Chem B 2010; 114:4565-71. [DOI: 10.1021/jp910948w] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Dibyendu Kumar Sasmal
- Physical Chemistry Department, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700 032, India
| | - Supratik Sen Mojumdar
- Physical Chemistry Department, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700 032, India
| | - Aniruddha Adhikari
- Physical Chemistry Department, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700 032, India
| | - Kankan Bhattacharyya
- Physical Chemistry Department, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700 032, India
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94
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Lai Y, Zhuang H, Xie K, Gong D, Tang Y, Sun L, Lin C, Chen Z. Fabrication of uniform Ag/TiO2 nanotube array structures with enhanced photoelectrochemical performance. NEW J CHEM 2010. [DOI: 10.1039/b9nj00780f] [Citation(s) in RCA: 163] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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95
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Neouze MA. About the interactions between nanoparticles and imidazolium moieties: emergence of original hybrid materials. ACTA ACUST UNITED AC 2010. [DOI: 10.1039/c0jm00616e] [Citation(s) in RCA: 119] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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96
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Yu P, Qian Q, Wang X, Cheng H, Ohsaka T, Mao L. Potential-controllable green synthesis and deposition of metal nanoparticles with electrochemical method. ACTA ACUST UNITED AC 2010. [DOI: 10.1039/c0jm01293a] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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