Organotrialkoxysilane-Functionalized Noble Metal Monometallic, Bimetallic, and Trimetallic Nanoparticle Mediated Non-Enzymatic Sensing of Glucose by Resonance Rayleigh Scattering

Organotrialkoxysilanes like 3-aminopropyltrimethoxysilane (3-APTMS)-treated noble metal cations were rapidly converted into their respective nanoparticles in the presence of 3-glycidoxypropylytrimethoxysilane (3-GPTMS). The micellar activity of 3-APTMS also allowed us to replace 3-GPTMS with other suitable organic reagents (e.g., formaldehyde); this approach has significant advantages for preparing bimetallic and trimetallic analogs of noble metal nanoparticles that display efficient activity in many practical applications. The formation of monometallic gold, silver, and palladium nanoparticles, bimetallic Ag-Pd, and Au-Pd nanoparticles at various ratios of noble metal cations, and trimetallic Ag-Au-Pd nanoparticles were studied; their biocatalytic activity in non-enzymatic sensing of glucose based on monitoring synchronous fluorescence spectroscopy (SFS) was assessed. Of these nanoparticles, Au-Pd made with an 80:20 Au:Pd ratio displayed excellent catalytic activity for glucose sensing. These nanoparticles could also be homogenized with Nafion to enhance the resonance Rayleigh scattering (RRS) signal. In this study, the structural characterization of noble metal nanoparticles as well as bi- and tri-metallic nanoparticles in addition to their use in non-enzymatic sensing of glucose are reported.

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Metallic nanoparticles made in flow and their catalytic applications in organic synthesis

Nanotechnology Reviews ◽

10.1515/ntrev-2013-0017 ◽

2014 ◽

Vol 3 (1) ◽

pp. 65-86 ◽

Cited By ~ 28

Author(s):

Elnaz Shahbazali ◽

Volker Hessel ◽

Timothy Noël ◽

Qi Wang

Keyword(s):

Metal Nanoparticles ◽

Organic Synthesis ◽

Metallic Nanoparticles ◽

Noble Metal Nanoparticles ◽

Synthesis Methods ◽

Highly Active ◽

Operational Window ◽

Gold Silver ◽

Recent Developments ◽

Silver Palladium

AbstractThis paper reviews recent developments on the synthesis of noble metal nanoparticles in micro and millifluidic devices and their catalytic application in organic flow synthesis. A variety of synthesis methods using microfluidics is presented for gold, silver, palladium, platinum, and copper nanoparticles, including the formation in single-phase flows and multiphase flows. In the field of organic chemistry, metal nanoparticles can be used as catalysts. This can lead to remarkably improved reaction performance in terms of minimizing the reaction time and higher yields. In this context, various applications of those metal nanoparticles as catalysts in microfluidic devices are highlighted at selected examples. As a new direction and operational window, nanocatalysts may be synthesized in situ in flow and directly utilized in an organic synthesis. This allows making use of highly active, yet instable catalyst species, which may only have a very short life of a few seconds – a type of flashed nanocatalyst organic synthesis.

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The Isocyanurate-Carbamate-Bridged Hybrid Mesoporous Organosilica: An Exceptional Anchor for Pd Nanoparticles and a Unique Catalyst for Nitroaromatics Reduction

Catalysts ◽

10.3390/catal11050621 ◽

2021 ◽

Vol 11 (5) ◽

pp. 621

Author(s):

Ali Zebardasti ◽

Mohammad G. Dekamin ◽

Esmail Doustkhah

Keyword(s):

Mesoporous Silica ◽

Metal Nanoparticles ◽

Noble Metal ◽

Room Temperature ◽

Heterogeneous Catalysts ◽

Pd Nanoparticles ◽

Noble Metal Nanoparticles ◽

Green Catalyst ◽

Mesoporous Organosilica ◽

Mesoporous Organosilicas

Hybridisation of mesoporous organosilicas (MO) to reinforce the surface capability in adsorption and stabilisation of noble metal nanoparticles is of great attention in generating/supporting noble metal within their matrices and transforming them into efficient heterogeneous catalysts. Here, we used a unique hybrid of organic-inorganic mesoporous silica in which pore profile pattern was similar to the well-known mesoporous silica, SBA-15 for catalysis. This hybrid mesoporous organosilica was further engaged as a support in the synthesis and stabilisation of Pd nanoparticles on its surface, and then, the obtained Pd-supported MO was employed as a heterogeneous green catalyst in the conversion of aqueous p-nitrophenol (PNP) to p-aminophenol (PAP) at room temperature with efficient recyclability.

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3-Aminopropyltrimethoxysilane Mediated Controlled Synthesis of Functional Noble Metal Nanoparticles and Its Multi-Metallic Analogues in the Presence of Small Organic Reducing Agents for Selective Application

MRS Advances ◽

10.1557/adv.2018.93 ◽

2018 ◽

Vol 3 (15-16) ◽

pp. 789-801

Author(s):

Prem C. Pandey ◽

Govind Pandey

Keyword(s):

Metal Nanoparticles ◽

Noble Metal ◽

Metallic Nanoparticles ◽

Present Report ◽

Reducing Agents ◽

Noble Metal Nanoparticles ◽

Practical Significance ◽

Similar Process ◽

Controlled Synthesis ◽

Polarity Index

ABSTRACTSynthesis of functional noble metal nanoparticles (AuNPs, AgNPs, and PdNPs) and its multi-metallic analogues have received greater attentions for selective applications. The selective applications of the these nanoparticles essentially requires the processability of as synthesized nanoparticles in the medium of desired polarity index that manifest the potential exploration of nanomaterial based design in targeted area. The use of conventional reducing and stabilizing agents during routine synthesis of such nanoparticles are not suitable with the system of practical significance and require additional reagents that limit the optimum activity of nanomaterial in targeted design. According there is a challenging issue in the synthesis of noble metal nanoparticles that allow the controlled synthesis of such nanoparticles involving same starting material with option to control the processability of as generated nanomaterial in the system of desired polarity index. The present report is focused on such challenging issues. We have found that 3-aminopropyltrimethoxysilane (3-APTMS) capped noble metal cations can be precisely converted into respective monometallic, bimetallic and trimetallic analogues and can be made processable in water at one end having controlled option to reversed the processability of the same in the toluene as a function of small organic reducing agents. The organic reducing agents not only convert 3-APTMS-capped noble cations into respective nanoparticles but also control the processability of the as generated nanoparticles in the systems of desired polarity index. The similar process also allows the synthesis of function bimetallic and tri-metallic nanoparticles. The role of cyclohexanone, formaldehyde and acetone in the presence of 3-APTMS is reported.

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Composites of silver nanoparticles and poly(vinylidene fluoride-trifluoroethylene)copolymer: Preparation as well as structural and electrical characterization

MRS Proceedings ◽

10.1557/proc-1182-ee13-02 ◽

2009 ◽

Vol 1182 ◽

Author(s):

Michael Wegener ◽

Tonino Greco

Keyword(s):

Silver Nanoparticles ◽

Dielectric Properties ◽

Metal Nanoparticles ◽

Noble Metal ◽

Surface Plasmon ◽

Metallic Nanoparticles ◽

Photon Absorption ◽

Noble Metal Nanoparticles ◽

Pyroelectric Properties ◽

Inorganic Particles

AbstractComposites comprising of polymers and metal nanoparticles are of great interest in regard to electronic and opto-electronic applications. The preparation of such nanocomposites with homogenously dispersed particles usually cannot be solved by mixing the polymer and the desired isolated colloids due to strong agglomeration tendency of the metallic nanoparticles. Consequently, nanocomposites with colloids have been prepared by synthesis of the inorganic particles in situ, for instance in solution, and then mixed with the polymer solution.Extensive attention has been given to the study of the plasmonic properties of noble metal nanoparticles as a result of their potential application as waveguides, photonic circuits, and sensors [1]. Surface plasmon polaritons are excited when electromagnetic radiation causes coherent oscillations of the conducting electrons of noble metal nanoparticles such as gold, silver or copper. The selective photon absorption and scattering allow the monitoring of the optical properties of the nanoparticles by conventional spectroscopic methods like UV-vis spectroscopy. Previous investigations show that the surface plasmon resonance frequency is extremely sensitive to the size, shape, and the surrounding dielectric environment of the nanoparticles [2].In order to obtain multifunctional composites electro-active polymers (EAP) can be chosen as matrix materials. EAPs such as polyvinylidene fluoride (PVDF) and its copolymer with trifluoroethylene (P(VDF-TrFE)) show a ferroelectric polarization accompanied with piezo- and pyroelectric properties. Both polymers are suitable for composite preparation as earlier studies have shown, e.g. performed on ceramic-polymer composites in order to optimize their piezo- and pyroelectric properties and to adjust their dielectric properties, respectively. Recently, PVDF with embedded metallic nanoparticles was studied regarding the kinetics of film preparation, dispersion and resulting properties [3].In this work, the influence of homogenously dispersed silver-nanoparticles in electro-active polymers such as PVDF and P(VDF-TrFE) has been investigated over a broad range of mass fractions of silver. For low silver nanoparticle content (up to 3wt.%) the surface plasmon polariton resonance peak can be observed in the blue spectral region. From the infrared spectra it is concluded that no significant degradation of the polymers occurs. Higher silver amounts cause the formation of fractal-like agglomerates. Thus, a high extinction cross section in the visible and infrared spectral range is found. Furthermore, the influence of the silver mass fraction to the thermal, electrical and dielectric properties of the nanocomposites is discussed in detail.[1] S. A. Maier, H. A. Atwater, J. Appl. Phys. 2005, 98, 011101-10. [2] J. J. Mock, et al, J. Chem. Phys. 2002, 116, 6755-6759.[3] J. Compton, et al, Makromol. Symp. 2007, 247, 182-189.

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Synthesis of noble metal nanoparticles and their non-ordered superstructures

Philosophical Transactions of The Royal Society A Mathematical Physical and Engineering Sciences ◽

10.1098/rsta.2009.0274 ◽

2010 ◽

Vol 368 (1915) ◽

pp. 1385-1404 ◽

Cited By ~ 49

Author(s):

Nadja C. Bigall ◽

Alexander Eychmüller

Keyword(s):

Metal Nanoparticles ◽

Noble Metal ◽

Cost Effective ◽

Noble Metal Nanoparticles ◽

Colloidal Solutions ◽

Short Introduction ◽

The Third ◽

Organic Templates ◽

Gold Silver ◽

The Given

This article highlights our recent work concerning the synthesis of metal nanoparticles and their non-ordered superstructures. After a short introduction, the basic synthetic procedures are explained for the nanoparticles used for the assemblies. Furthermore, a fabrication method is itemized for very monodisperse platinum nanoparticles in aqueous solution ranging in diameter from 10 to 100 nm showing distinct optical properties. The next section deals with the synthesis of non-ordered hydro- and aerogels from the as-prepared sols. Very light large surface materials from gold, silver, platinum and gold–silver and platinum–silver sols can be fabricated with the given method. Another way to ultralight superstructures of noble metal nanoparticles using fungi as templates is described in the third section. Although fungi grow inside the colloidal solutions they can assemble the nanoparticles onto their surfaces. These hybrid systems are thus extremely interesting supported superstructures for applications in heterogeneous catalysis, since the numbers of nanoparticles on the fungus can easily be tuned, and the fabrication process is cost-effective, environmentally friendly and the organic templates can be easily removed by simple combustion for regaining the noble metal.

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Highly Ordered Hybrid Mesoporous Organosilica: An Exceptional Anchor for Pd Nanoparticles and Catalyst Nitroaromatic Reduction

10.21203/rs.3.rs-153162/v1 ◽

2021 ◽

Author(s):

Ali Zebardasti ◽

Mohammad G. Dekamin ◽

Esmail Doustkhah

Keyword(s):

Mesoporous Silica ◽

Metal Nanoparticles ◽

Noble Metal ◽

Room Temperature ◽

Pd Nanoparticles ◽

Noble Metal Nanoparticles ◽

Green Catalyst ◽

Mesoporous Organosilica

Abstract Hybridization of mesoporous organosilica (MO) to reinforce the surface capability in adsorption and stabilization of noble metal nanoparticles are of great attention in generating noble metal-based catalysts. Here, we used a unique hybrid of organic-inorganic mesoporous silica which in pore profile pattern was similar to the well-known mesoporous silica, SBA-15. This hybrid mesoporous silica was further incorporated in the synthesis and stabilization of Pd nanoparticles on its surface and then, the obtained Pd supported MO, was employed as a heterogeneous green catalyst in the conversion of p-nitrophenol (PNP) to p-aminophenol (PAP) at room temperature with efficient recyclability.

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One-Pot Facile Synthesis of Noble Metal Nanoparticles Supported on rGO with Enhanced Catalytic Performance for 4-Nitrophenol Reduction

Molecules ◽

10.3390/molecules26237261 ◽

2021 ◽

Vol 26 (23) ◽

pp. 7261

Author(s):

Xiaolong Zhang ◽

Shilei Jin ◽

Yuhan Zhang ◽

Liyuan Wang ◽

Yang Liu ◽

...

Keyword(s):

Metal Nanoparticles ◽

Noble Metal ◽

Measurement Techniques ◽

Catalytic Performance ◽

Noble Metal Nanoparticles ◽

Pt Catalyst ◽

One Pot ◽

K Value ◽

Nitrophenol Reduction ◽

Gold Silver

In this study, reduced graphene oxide (rGO)-supported noble metal (gold, silver, and platinum) nanoparticle catalysts were prepared via the one-pot facile co-reduction technique. Various measurement techniques were used to investigate the structures and properties of the catalysts. The relative intensity ratios of ID/IG in rGO/Au, rGO/Ag, rGO/Pt, and GO were 1.106, 1.078, 1.047, and 0.863, respectively. The results showed the formation of rGO and that noble metal nanoparticles were decorated on rGO. Furthermore, the catalytic activities of the designed nanocomposites were investigated via 4-nitrophenol. The catalysts were used in 4-nitrophenol reduction. The catalytic performance of the catalysts was evaluated using the apparent rate constant k values. The k value of rGO/Au was 0.618 min−1, which was higher than those of rGO/Ag (0.55 min−1) and rGO/Pt (0.038 min−1). The result proved that the rGO/Au catalyst exhibited a higher catalytic performance than the rGO/Ag catalyst and the rGO/Pt catalyst. The results provide a facile method for the synthesis of rGO-supported nanomaterials in catalysis.

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