Ag triangular nanoplates synthesized by photo-induced reduction: Structure analysis and stability

Murayama, Haruno; Hashimoto, Naomi; Tanaka, Hideki

doi:10.1016/j.cplett.2009.10.015

Cited by 15 publications

(7 citation statements)

References 27 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…rapid oxidation) of the Ag nanoparticles, generating Ag + . [120,133] Consistent with the chemical reaction for the oxidation of Ag 0 by O 2 (Figure 3 A), the photo-conversion process results in a measurable increase in the pH of the growth solution. [120,121] Indeed, some of the most compelling evidence for the triangular prisms being generated by Ag + reduction is that under appropriate conditions, the spherical Ag nanoparticle seeds can be replaced with a Ag + salt (most commonly, AgNO 3 ) and triangular prisms can still be produced.…”

Section: Chemical Mechanisms Of Growthsupporting

confidence: 69%

Plasmon‐Mediated Syntheses of Metallic Nanostructures

2013

View full text Add to dashboard Cite

The ability to prepare noble metal nanostructures of a desired composition, size, and shape enables their resulting properties to be exquisitely tailored, which has led to the use of these structures in numerous applications, ranging from medicine to electronics. The prospect of using light to guide nanoparticle reactions is extremely attractive since one can, in principle, regulate particle growth based on the ability of the nanostructures to absorb a specific excitation wavelength. Therefore, using the nature of light, one can generate a homogenous population of product nanoparticles from a heterogeneous starting population. The best example of this is afforded by plasmon-mediated syntheses of metal nanoparticles, which use visible light irradiation and plasmon excitation to drive the chemical reduction of Ag(+) by citrate. Since the initial discovery that Ag triangular prisms could be prepared by the photo-induced conversion of Ag spherical nanoparticles, plasmon-mediated synthesis has become a highly controllable technique for preparing a number of different Ag particles with tight control over shape, as well as a wide variety of Au-Ag bimetallic nanostructures. We discuss the underlying physical and chemical factors that drive structural selection and conclude by outlining some of the important design considerations for controlling particle shape as learned through studies of plasmon-mediated reactions, but applicable to all methods of noble metal nanocrystal synthesis.

show abstract

Section: Chemical Mechanisms Of Growthsupporting

confidence: 69%

Plasmon‐Mediated Syntheses of Metallic Nanostructures

2013

View full text Add to dashboard Cite

show abstract

“…There are several reports of blue‐colored AgNPs being easily oxidized by oxygen in the air without protective reagents. For example, Tanaka and co‐workers, reported the color change of triangular AgNPs in a colloidal solution as follows: When the colloidal solution was air‐bubbled, the color of the solution changed to green and then turned to colorless. When water was added to the photoirradiated solution, the solution immediately turned to light red and then colorless.…”

Section: Resultsmentioning

confidence: 99%

“…For example, Tanaka and co‐workers reported the synthesis and NIR response of triangle‐shaped AgNPs. However, these AgNPs exhibited no extinction at wavelengths longer than 1100 nm . Yamashita and co‐workers reported the NIR response of AgNPs in mesoporous silica.…”

Section: Introductionmentioning

confidence: 99%

Preparation of Stable Silver Nanoparticles Having Wide Red‐To‐Near‐Infrared Extinction

et al. 2018

View full text Add to dashboard Cite

The synthesis of silver nanoparticles (AgNPs) within the interlayer space of transparent layered titania nanosheet (TNS) films is investigated. A considerable number of silver ions (≈70% against the cation exchange capacity of the TNS) are intercalated in the TNS films using methyl‐viologen‐containing TNSs as a precursor. The silver ion (Ag + )‐containing TNS films are treated with aqueous sodium tetrahydroborate (NaBH 4 ), resulting in a gradual color change to bright blue. Various structural analyses clearly show that crystalline AgNPs are generated within the interlayer space of the TNSs. The NaBH 4 ‐treated films show intense and characteristic near‐infrared (NIR) extinction spectra up to 1800 nm. The stability of the AgNPs within the TNS against oxygen and moisture is also investigated, and 96% and 82% of the AgNPs remain after standing in air for 1 month and 1 year, respectively. The NIR extinctions of the AgNP‐containing TNS films are further extended by employing different preparation procedures, for example, using sintered TNS films as starting materials and irradiating the Ag + ‐containing TNSs with ultraviolet (UV) light. The obtained AgNP‐containing TNS films exhibit photochemical activities in the production of hydrogen from ammonia borane under visible‐light irradiation and the decomposition of nitrogen monoxide under UV‐light irradiation.

show abstract

“…According to the homogeneous size and shape distribution, the presented flow-through obtained triangular nanoprisms are also able to withstand the comparison to nanoprisms from various other preparation methods, which were reported in the literature before. 11,32,34,35,38 4. CONCLUSIONS The synthesis of prismatic Ag nanoparticles having a triangular base area was successfully implemented in a microcontinuous flow-through system using the method of the microsegmented flow.…”

Section: Resultsmentioning

confidence: 99%

Microsegmented Flow-Through Synthesis of Silver Nanoprisms with Exact Tunable Optical Properties

et al. 2012

View full text Add to dashboard Cite

In this work, a multistep microcontinuous flow-through synthesis procedure for the generation of homogeneous, high-quality silver nanoprisms is presented. The particle synthesis is based on the wet chemical reduction of silver nitrate in the presence of the polyanionic polymer poly(sodium styrenesulphonate). To obtain a high yield of homogeneous prism-shaped Ag nanoparticles with a triangular base, two main experimental steps are necessary. The first step is the synthesis of seed particles. To match the quality criteria for small, homogeneous seed particles, the synthesis was carried out in a microcontinuous flow-through system. Constant residence times and an effective mixing of the reactants were realized by the application of the microsegmented flow technique. The advantage of good reactant mixing was also adapted in the second experimental step. The growth of silver nanoprisms by reduction of silver nitrate on the noncapped surfaces of the seed particles was again carried out within microfluid segments during a continuous flow-through synthesis. The obtained colloidal solutions of both, Ag seeds and Ag nanoprisms, were analyzed using differential centrifugal sedimentation, UV–vis spectrophotometry, and scanning electron microscopy. The size distributions of the product particles of the individual process steps were extremely narrow. For the Ag seed particles, an average particle diameter of 3.8 nm with a distribution half-width of 2.3 nm was found. The edge length of the Ag nanoprisms could be varied between 35 and 180 nm, while the size distribution remained narrow and the yield of particles of the desired shape high. Because of the strong sensitivity of the optical properties of the nanoprisms from the geometrical aspects, Ag nanoprisms promise a high potential for sensor applications. Constraints on nanoparticles presented by these applications, such as uniformity and narrow size distributions, can be met by microreaction technology. In particular, by applying a microsegmented flow, an improvement of the product quality can be achieved because of the enhanced segment-internal mixing and the suppression of a residence time distribution.

show abstract

Ag triangular nanoplates synthesized by photo-induced reduction: Structure analysis and stability

Cited by 15 publications

References 27 publications

Plasmon‐Mediated Syntheses of Metallic Nanostructures

Plasmon‐Mediated Syntheses of Metallic Nanostructures

Preparation of Stable Silver Nanoparticles Having Wide Red‐To‐Near‐Infrared Extinction

Microsegmented Flow-Through Synthesis of Silver Nanoprisms with Exact Tunable Optical Properties

Contact Info

Product

Resources

About