Dr. B.P.S. Chauhan would like to gratefully acknowledge William Paterson University for assigned release time (ART) award for part of the research described here and also for the research program in general.

주 : 추가의 정제로 제조 업체에서와 같이 모든 시약이 사용됩니다. 반응이 완료 절감을 보장하기 위해 UV-마주 분광법을 통해 최대 일주일 동안 관찰 하였다. 모든 반응은 벤트 후드에서 수행하고 적절한 안전 복장 장갑, 눈 고글, 및 실험실 코트를 포함한 모든 시간, 착용한다. 실버 나노 입자의 합성 (1) <ol><li> 50 ㎖ 삼각 플라스크에 직접 질산은 0.0169 g (0.1 밀리몰)을 칭량. </li><li> 초순수 MΩ 및 자석 교반기 막대 18.2 20ml에 추가한다. 증발을 방지하기 위해 마개 플라스크를 커버. </li><li> 오일 배스에​​ 넣어 플라스크를 교반기 / 핫 플레이트 상에 위치하며 온도는 60 ° C로 유지되도록. </li><li> 천천히 정밀 마이크로 피펫을 사용하여 2 AST 144 μL (0.2 밀리몰)를 추가합니다. 모든 실란을 보장하기 위해 용액을 세척 피펫 여러번 용액으로 전달된다. </li><li> UV - 마주 분광 측정을제 5 절에 나열된 프로토콜에 따라. </li><li> 6 시간 후, 오일 조로부터 제거하고 샘플을 보관, TEM, FTIR 및 추가 분석을 위해 샘플을 20 ㎖ 바이알로 옮긴다. 주 : 금 및 팔라듐 나노 입자의 합성은 216 μL (0.3 밀리몰)의 2- AST를 요구 금 나노 입자를 제외하고 동일한 방법 및 화학량 론적 양을 따른다. 반응은 최대 2 주 동안 나노 입자를 생성하기 위해 계속 될 수 있지만, 속도는 초기 속도에 비해 중요하지 않다. </li></ol> 2. 투과 전자 현미경 (TEM) 샘플 준비 <ol><li> 그 샘플을 실온으로 냉각해야합니다. </li><li> 여과지의 깨끗한 조각에 200 탄소 메쉬 formvar 코팅 된 구리 그리드를 배치합니다. </li><li> 1 ml의 플라스틱 파스퇴르 피펫, 캐스팅 드롭 직접 그리드 상에 나노 입자 시료의 약 60 μl를 사용. </li><li> 그리드 이미징 전에 24 시간 동안 건조하도록 허용합니다. </li><li> 다음의 조건 고해상도 TEM 화상을 보자10 μA 전류 및 전압을 22 kV의 가속 100. </li></ol> (3) 핵 자기 공명 (NMR) 샘플 준비 참고 : RT에서 NMR을 수행합니다. 고온에서 얻어지는 스펙트럼 신호의 품질을 저하하는 유착 수있다. <ol><li> 정밀 피펫, 피펫 깨끗한 NMR 튜브에 중수소 가스 (D 2 O)의 50 μl를 사용. </li><li> 또 다른 깨끗한 정밀 피펫, 피펫 같은 NMR 튜브에 나노 입자 시료의 400 μl를. <ol><li> 샘플을 NMR 관의 내벽에 부착 될 수 있으므로 천천히 NMR 튜브에 솔루션을 추가한다. 샘플이 부착 않으면 튜브 캡과 하부의 해결책을 강제 튜브의 상단을 흔들어. </li></ol></li><li> NMR 튜브를 반전 반복적으로 흔들어하여 샘플을 섞는다. </li><li> 제조업체에서 제공 NMR 프로토콜에 의해 지시 사항을 다음 NMR에 장소 샘플 튜브. 1000 검사의 위쪽으로 적절한 입술에 대한 필요가있다1 H NMR 양성자 펄스 프로그램 olution. 참고 : NMR 튜브 벽이 깨끗해야합니다. 튜브의 외벽 전에 스펙트럼 명확성을 위해 분석에 마이크로 화이버 또는 보풀이없는 천으로 닦아하는 것이 좋습니다. </li><li> 완료되면 샘플을 폐기하십시오. 부모 용액에 샘플을 반환하지 않습니다. </li></ol> 4. 푸리에 변환 적외선 (FTIR) 분광학 샘플 준비 변환 <ol><li> 작은 유리 용기에 나노 입자 샘플 2 ㎖를 놓습니다. 3 ML 튜브 또는 1 DRAM 유리 병은 잘 작동합니다. </li><li> 콕 장착 진공 데시 케이 터 내에서 유리 용기를 배치하여 샘플을 건조. </li><li> 진공 펌프 장치에 건조기를 연결합니다. 샘플의 건조는 진공 강도에 따라 몇 시간이 걸릴 수 있습니다. 용기 내의 액체 표시도하지 고려 샘플 건조. </li><li> 깨끗한 주걱을 사용하여 샘​​플을 긁고 고체 물질을 수집합니다. </li><li> 의 ZnSe의 크리스 í 장착 ATR-FTIR 분광기에 고체 물질을 배치알 다이오드 레이저. </li><li> 4,000-500 cm 사이 (32) 검사를 통합 FTIR 스펙트럼을 구하는 -1 2.0의 스펙트럼 해상도. 공기 배경 (23)를 사용합니다. </li></ol> 5. UV-마주 분광학 샘플 준비 <ol><li> 그 포화 분광 분석에서 발생하지 않도록 물 나노 시료 1-10 희석에 나노 입자 샘플에 대해 UV-비스 분광법을 수행. </li><li> 반응이 반 시간 간격으로 실행되는 동안 UV-VI의 나노 입자 샘플을 제거합니다. </li><li> 정밀 피펫을 사용하여, 나노 입자 재료 100 ㎕을 제거하고 플라스틱 큐벳에 놓는다. </li><li> 같은 큐벳에 초순수의 1 ML을 추가하고 피펫 여러 번 세척하여 완전히 혼합한다. </li><li> 250-800 nm의 사이에 기록 UV-마주 흡수 스펙트럼. </li><li> 분석 한 후, 반응 샘플을 반환하지 않습니다. 적절한 방법으로 분석 폐기하십시오. </li></ol>

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충돌하는 금전적 이해 관계가 없습니다.

이 논문에보고 된 염은 금속으로 시험 하였다 유일한 염이다. 그 결과,이 반응 전략은 모든 금속 염, 특히 금 작동 것이 불확실하다. 물에서 이러한 염의 용해도는 반응 시간, 형태, 및 수율의 관점에서, 반응의 결과에 영향을 미칠 수있다. 모든 반응에서 실란 이미 용해 된 금속 염 용액에 첨가 하였다. 이들 반응은 흡습성 또는 조해성 (18) 일 수있다 금속염의 작은 농?...

수요 디자이너 나노 증가 애플리케이션도록 합성의 다양한 방법을 수행. 레이저 어블 레이션 법 또는 화학적 에칭과 같은 &#39;하향식 &quot;방법은, 우수한 제어 성 및 신뢰성 서브 마이크론 수준까지 물질을 분석하는 기능을 위해 사용되어왔다. 이들 방법은 목적하는 나노 크기가 감소함에 따라 일반적으로 제조 비용을 증가 미세한 성분으로 처리 될 벌크 물질에 의존한다. 이에 합성의 다른 방법은 분자 수준에서의 합성을 제어하고 원하는 나노 구조물에 축적 &quot;상향식&quot;접근 방식이다. 이는 이러한 나노 구조 물질 (1)의 생성에 바람직한 자기 조립, 기능 수동성 및 안정성 제어의 심각한 정도를 부여한다. 분자 수준에서 작업함으로써, 하이브리드 나노 구조물의 동일한 내에 두 물질의 장점을 제공하고 생성 할 수있다레. 나노 물질은 상향식 전략을 통해 합성 같이, 방법은 입자 크기, 형태, 질감, 소수성 다공성 전하 및 기능이 제어하기 위해 이용 될 필요가있다. 금속 코어 나노 합성 초기 금속염 차례로 다른 입자의 핵을 지시 제로 가의 입자를 생성하는 촉매 공정에서 감소된다. 이는 클러스터링에 이르게 그리고 마지막으로 나노 입자 생산 3. 생성 된 나노 입자의 크기를 조절하고 용액으로부터 침전시키는 것을 방지하기 위해, 이러한 리간드, 계면 활성제, 이온 전하, 큰 중합체 안정 화제는 또한 응집 4-10에서 나노 입자를 차단하는 능력을 위해 이용된다. 이들 재료 인해 부피 기의 존재 또는 쿨롱 반발 1-3 입체 장해를 통해 하나, 나노 입자의 반 데르 발스 인력을 억제한다. t에서그의 일, 실란을 사용하여 다양한 금속 코어 나노 입자의 생성을위한 용이 한 번 포트 합성 전략, N- (2- 아미노 에틸) -3- aminosilanetriol (2- AST)는 (도 1)에 제공된다. 이 화합물에 대한 리간드는 비교적 높은 효율로 금속 나노 입자를 금속 전구체를 환원 및 안정화 할 수있다. 본 세 실라 부분은 가교 할 수있는이 그 매트릭스 (도 2) 내에서 나노 입자를 함침 실란 중합체의 상호 연결된 네트워크를 형성한다. 용이 물의 존재하에 가수 분해를 거쳐 가장 실란 달리,이 소수성 화합물은 목적, 안정성 및 제어를위한 유용 물에 안정화된다.

<table><tbody><tr><td>n-(2-aminoethyl)-3-aminosilanetriol (2-AST)</td><td>Gelest</td><td>SIA0590.0</td><td>25% in H&lt;sub&gt;2&lt;/sub&gt;O</td></tr><tr><td>Silver nitrate</td><td>Sigma Aldrich</td><td>S6506</td><td></td></tr><tr><td>Gold(III) chloride trihydrate</td><td>Sigma Aldrich</td><td>520918</td><td></td></tr><tr><td>Palladium(II) Nitrate</td><td>Alfa Aesar</td><td>11035</td><td></td></tr><tr><td>Deuterium Dioxide</td><td>Cambridge Isotope Laboratories</td><td>DLM-4-100</td><td></td></tr></tbody></table>

generation of zerovalent metal core nanoparticles using n-(2-aminoethyl)-3-aminosilanetriol

In this work, a facile one-pot reaction for the formation of metal nanoparticles in a water solution through the use of n-(2-aminoethyl)-3-aminosilanetriol is presented. This compound can be used to effectively reduce and complex metal salts into metal core nanoparticles coated with the compound. By controlling the concentrations of salt and silane one is able to control reaction rates, particle size, and nanoparticle coating. The effects of these changes were characterized through transmission electron microscopy (TEM), UV-Vis spectrometry (UV-Vis), Nuclear Magnetic Resonance spectroscopy (NMR) and Fourier Transform Infrared spectroscopy (FTIR). A unique aspect to this reaction is that usually silanes hydrolyze and cross-link in water; however, in this system the silane is water-soluble and stable. It is known that silicon and amino moieties can form complexes with metal salts. The silicon is known to extend its coordination sphere to form penta- or hexa-coordinated species. Furthermore, the silanol group can undergo hydrolysis to form a Si-O-Si silica network, thereby transforming the metal nanoparticles into a functionalized nanocomposites.

나노 입자 형성은 각각의 금속 나노 입자에 대한 특징적인 피크를 생성한다으로 반응 UV-비스 분석법으로 모니터링 하였다. 합성 된 물질의 최종 분석은 TEM과 FTIR을 통해 수행되었다. FTIR 스펙트럼은 샘플의 건조 분말을 얻었다. 입도 분석은 TEM 및 평균화 결과로 얻어지는 화상으로부터 나노 입자의 직경을 측정함으로써 달성 될 수있다. <p class="jove_content" fo:keep-together.wi...

Watch this Scientific Journal Video about Generation of Zerovalent Metal Core Nanoparticles Using n-2-aminoethyl-3-aminosilanetriol at JoVE.com

Generation of Zerovalent Metal Core Nanoparticles Using n-2-aminoethyl-3-aminosilanetriol

A novel method for metal core nanoparticle synthesis using a water stable silanol is described.

영가 코어 금속 나노 입자의 생성은 사용 N- (2- 아미노 에틸) -3- aminosilanetriol

In this work, a facile one-pot reaction for the formation of metal nanoparticles in a water solution through the use of ...

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Chemistry

Generation of Zerovalent Metal Core Nanoparticles Using n-(2-aminoethyl)-3-aminosilanetriol

7.6K 조회수.  William Paterson University. A novel method for metal core nanoparticle synthesis using a water stable silanol is described.

비디오: Generation of Zerovalent Metal Core Nanoparticles Using n-2-aminoethyl-3-aminosilanetriol

Preparation of Silica Nanoparticles Through Microwave-assisted Acid-catalysis

Microwave-assisted synthetic techniques were used to quickly and reproducibly produce silica nanoparticle sols using an acid catalyst with nanoparticle diameters ranging from 30-250 nm by varying the reaction conditions. Through the selection of a microwave compatible solvent, silicic acid precursor, catalyst, and microwave irradiation time, these microwave-assisted methods were capable of overcoming the previously reported shortcomings associated with synthesis of silica nanoparticles using microwave reactors. The siloxane precursor was hydrolyzed using the acid catalyst, HCl. Acetone, a low-tan &#948; solvent, mediates the condensation reactions and has minimal interaction with the electromagnetic field. Condensation reactions begin when the silicic acid precursor couples with the microwave radiation, leading to silica nanoparticle sol formation. The silica nanoparticles were characterized by dynamic light scattering data and scanning electron microscopy, which show the materials&#39; morphology and size to be dependent on the reaction conditions. Microwave-assisted reactions produce silica nanoparticles with roughened textured surfaces that are atypical for silica sols produced by St&#246;ber&#39;s methods, which have smooth surfaces.

Silica nanoparticles were prepared using acid-catalysis of a siloxane precursor and microwave-assisted synthetic techniques resulting in the controlled growth of nanomaterials ranging from 30-250 nm in diameter. The growth dynamics can be controlled by varying the initial silicic acid concentration, time of the reaction, and temperature of reaction.

전자 레인지를 이용한 산 - 촉매 반응을 통해 실리카 나노 입자의 제조

Microwave-assisted synthetic techniques were used to quickly and reproducibly produce silica nanoparticle sols using an acid catalyst with nanoparticle ...

연구

화학

Gold Nanostar Synthesis with a Silver Seed Mediated Growth Method

The physical, chemical and optical properties of nano-scale colloids depend on their material composition, size and shape 1-5. There is a great interest in using nano-colloids for photo-thermal ablation, drug delivery and many other biomedical applications 6. Gold is particularly used because of its low toxicity 7-9. A property of metal nano-colloids is that they can have a strong surface plasmon resonance 10. The peak of the surface plasmon resonance mode depends on the structure and composition of the metal nano-colloids. Since the surface plasmon resonance mode is stimulated with light there is a need to have the peak absorbance in the near infrared where biological tissue transmissivity is maximal 11, 12.
We present a method to synthesize star shaped colloidal gold, also known as star shaped nanoparticles 13-15 or nanostars 16. This method is based on a solution containing silver seeds that are used as the nucleating agent for anisotropic growth of gold colloids 17-22. Scanning electron microscopy (SEM) analysis of the resulting gold colloid showed that 70 % of the nanostructures were nanostars. The other 30 % of the particles were amorphous clusters of decahedra and rhomboids. The absorbance peak of the nanostars was detected to be in the near infrared (840 nm). Thus, our method produces gold nanostars suitable for biomedical applications, particularly for photo-thermal ablation.

We synthesized star shaped gold nanostars using a silver seed mediated growth method. The diameter of the nanostars ranges from 200 to 300 nm and the number of tips vary from 7 to 10. The nanoparticles have a broad surface plasmon resonance mode centered in the near infrared.

실버 씨앗 중재 성장 방법과 골드 Nanostar 합성

The physical, chemical and optical properties of nano-scale colloids depend on their material composition, size and shape 1-5. There is a great interest ...

생체공학

Using Polystyrene-block-poly(acrylic acid)-coated Metal Nanoparticles as Monomers for Their Homo- and Co-polymerization

We present a template-free method for &#8220;polymerizing&#8221; nanoparticles into long chains without side branches. A variety of nanoparticles are encapsulated in polystyrene-block-poly(acrylic acid) (PSPAA) shells and then used as monomers for their self-assembly. Spherical PSPAA micelles upon acid treatment are known to assemble into cylindrical micelles. Exploiting this tendency, the core-shell nanoparticles are induced to aggregate, coalesce, and then transform into long chains. When more than one type of nanoparticles are used, random and block &#8220;copolymers&#8221; of nanoparticles can be obtained. Detailed procedures are reported for the PSPAA encapsulation of nanoparticles, homo- and co-polymerization of the core-shell nanoparticles, separation and purification of the resulting nanoparticle chains. Transformations of single-line chains into double- and triple-line chains are also presented. The synergy between the polymer shell and the embedded nanoparticles leads to an unusual chain-growth polymerization mode, giving long nanoparticle chains that are distinct from the products of the traditional step-growth aggregation process.

Using Polystyrene-block-polyacrylic acid-coated Metal Nanoparticles as Monomers for Their Homo- and Co-polymerization

We report protocols for &#8220;polymerizing&#8221; various types of polymer-encapsulated metal nanoparticles into long chains of &#8220;homo-&#8220; and &#8220;co-polymers&#8221;.

폴리스타이렌을 사용하여<em&gt; 블록</em&gt; 폴리 (아크릴산) 및 이들의 단독 중합체는 공중합 용 단량체로 피복 된 금속 나노 입자

We present a template-free method for &#8220;polymerizing&#8221; nanoparticles into long chains without side branches. A variety of nanoparticles are ...

Reverse Microemulsion-mediated Synthesis of Monometallic and Bimetallic Early Transition Metal Carbide and Nitride Nanoparticles

A reverse microemulsion is used to encapsulate monometallic or bimetallic early transition metal oxide nanoparticles in microporous silica shells. The silica-encapsulated metal oxide nanoparticles are then carburized in a methane/hydrogen atmosphere at temperatures over 800 &#176;C to form silica-encapsulated early transition metal carbide nanoparticles. During the carburization process, the silica shells prevent the sintering of adjacent carbide nanoparticles while also preventing the deposition of excess surface carbon. Alternatively, the silica-encapsulated metal oxide nanoparticles can be nitridized in an ammonia atmosphere at temperatures over 800 &#176;C to form silica-encapsulated early transition metal nitride nanoparticles. By adjusting the reverse microemulsion parameters, the thickness of the silica shells, and the carburization/nitridation conditions, the transition metal carbide or nitride nanoparticles can be tuned to various sizes, compositions, and crystal phases. After carburization or nitridation, the silica shells are then removed using either a room-temperature aqueous ammonium bifluoride solution or a 0.1 to 0.5 M NaOH solution at 40-60 &#176;C. While the silica shells are dissolving, a high surface area support, such as carbon black, can be added to these solutions to obtain supported early transition metal carbide or nitride nanoparticles. If no high surface area support is added, then the nanoparticles can be stored as a nanodispersion or centrifuged to obtain a nanopowder.

A &#8220;removable ceramic coating method&#8221; is presented in visual format for the synthesis of non-sintered and metal-terminated monometallic and bimetallic early transition metal carbide and nitride nanoparticles with tunable sizes and crystal structures.

단본위제 및 바이메탈 조기 전이 금속 탄화물 및 질화물 나노 입자의 역 마이크로 에멀젼 매개 합성

A reverse microemulsion is used to encapsulate monometallic or bimetallic early transition metal oxide nanoparticles in microporous silica shells. The ...

Synthesis, Characterization, and Functionalization of Hybrid Au/CdS and Au/ZnS Core/Shell Nanoparticles

Plasmonic nanoparticles are an attractive material for light harvesting applications due to their easily modified surface, high surface area and large extinction coefficients which can be tuned across the visible spectrum. Research into the plasmonic enhancement of optical transitions has become popular, due to the possibility of altering and in some cases improving photo-absorption or emission properties of nearby chromophores such as molecular dyes or quantum dots. The electric field of the plasmon can couple with the excitation dipole of a chromophore, perturbing the electronic states involved in the transition and leading to increased absorption and emission rates. These enhancements can also be negated at close distances by energy transfer mechanism, making the spatial arrangement of the two species critical. Ultimately, enhancement of light harvesting efficiency in plasmonic solar cells could lead to thinner and, therefore, lower cost devices. The development of hybrid core/shell particles could offer a solution to this issue. The addition of a dielectric spacer between a gold nanoparticles and a chromophore is the proposed method to control the exciton plasmon coupling strength and thereby balance losses with the plasmonic gains. A detailed procedure for the coating of gold nanoparticles with CdS and ZnS semiconductor shells is presented. The nanoparticles show high uniformity with size control in both the core gold particles and shell species allowing for a more accurate investigation into the plasmonic enhancement of external chromophores.

The synthesis of uniform gold nanoparticles coated with semiconductor shells of CdS or ZnS is performed. The semiconductor coating is conducted by first depositing a silver sulfide shell and exchanging the silver cations for zinc or cadmium cations.

합성, 특성 및 하이브리드 금 / CD 및 금 /은 ZnS 코어 / 쉘 나노 입자의 작용 화

Plasmonic nanoparticles are an attractive material for light harvesting applications due to their easily modified surface, high surface area and large ...

Synthesis and Characterization of Supramolecular Colloids

Control over colloidal assembly is of utmost importance for the development of functional colloidal materials with tailored structural and mechanical properties for applications in photonics, drug delivery and coating technology. Here we present a new family of colloidal building blocks, coined supramolecular colloids, whose self-assembly is controlled through surface-functionalization with a benzene-1,3,5-tricarboxamide (BTA) derived supramolecular moiety. Such BTAs interact via directional, strong, yet reversible hydrogen-bonds with other identical BTAs. Herein, a protocol is presented that describes how to couple these BTAs to colloids and how to quantify the number of coupling sites, which determines the multivalency of the supramolecular colloids. Light scattering measurements show that the refractive index of the colloids is almost matched with that of the solvent, which strongly reduces the van der Waals forces between the colloids. Before photo-activation, the colloids remain well dispersed, as the BTAs are equipped with a photo-labile group that blocks the formation of hydrogen-bonds. Controlled deprotection with UV-light activates the short-range hydrogen-bonds between the BTAs, which triggers the colloidal self-assembly. The evolution from the dispersed state to the clustered state is monitored by confocal microscopy. These results are further quantified by image analysis with simple routines using ImageJ and Matlab. This merger of supramolecular chemistry and colloidal science offers a direct route towards light- and thermo-responsive colloidal assembly encoded in the surface-grafted monolayer.

A protocol for the synthesis and characterization of colloids coated with supramolecular moieties is described. These supramolecular colloids undergo self-assembly upon the activation of the hydrogen-bonds between the surface-anchored molecules by UV-light.

Control over colloidal assembly is of utmost importance for the development of functional colloidal materials with tailored structural and mechanical ...

A Rapid Synthesis Method for Au, Pd, and Pt Aerogels Via Direct Solution-Based Reduction

Here, a method to synthesize gold, palladium, and platinum aerogels via a rapid, direct solution-based reduction is presented. The combination of various precursor noble metal ions with reducing agents in a 1:1 (v/v) ratio results in the formation of metal gels within seconds to minutes compared to much longer synthesis times for other techniques such as sol-gel. Conducting the reduction step in a microcentrifuge tube or small volume conical tube facilitates a proposed nucleation, growth, densification, fusion, equilibration model for gel formation, with final gel geometry smaller than the initial reaction volume. This method takes advantage of the vigorous hydrogen gas evolution as a by-product of the reduction step, and as a consequence of reagent concentrations. The solvent accessible specific surface area is determined with both electrochemical impedance spectroscopy and cyclic voltammetry. After rinsing and freeze drying, the resulting aerogel structure is examined with scanning electron microscopy, X-ray diffractometry, and nitrogen gas adsorption. The synthesis method and characterization techniques result in a close correspondence of aerogel ligament sizes. This synthesis method for noble metal aerogels demonstrates that high specific surface area monoliths may be achieved with a rapid and direct reduction approach.

A rapid, direct solution-based reduction synthesis method to obtain Au, Pd, and Pt aerogels is presented.

Au, Pd, Pt Aerogels 직접 솔루션 기반 감소를 통해 빠른 합성 방법

Here, a method to synthesize gold, palladium, and platinum aerogels via a rapid, direct solution-based reduction is presented. The combination of various ...

Synthesis of Bimetallic Pt/Sn-based Nanoparticles in Ionic Liquids

We demonstrate a method for the synthesis of bimetallic nanoparticles consisting of Pt and Sn. A synthesis strategy is used in which the particular physico-chemical properties of ionic liquids (ILs) are exploited to control both nucleation and growth processes. The nanoparticles form colloidal sols of very high colloidal stability in the IL, which is particularly interesting in view of their use as quasi-homogeneous catalysts. Procedures for both nanoparticle extraction in conventional solvents and for nanoparticle precipitation are presented. The size, structure and composition of the synthesized nanocrystals are confirmed using inductively coupled plasma atomic emission spectroscopy (ICP-AES), X-ray diffraction analysis (XRD) and transmission electron microscopy (TEM) with energy-dispersive X-ray spectroscopy (EDX). By this, we show that the nanocrystals are random-type alloy and of small (2-3 nm) size. The catalytic activity and selectivity in the hydrogenation of &#945;,&#946;-unsaturated aldehydes is tested in a semi-continuous batch-type reactor. In this context, the bimetallic Pt/Sn-based nanoparticles reveal a high selectivity towards the unsaturated alcohol.

A protocol for the synthesis of bimetallic nanoparticles in ionic liquids and the procedure of their catalytic testing in the selective hydrogenation of unsaturated aldehydes are described.

이온 액체의 바이메탈 Pt/Sn 기반 나노 입자의 합성

We demonstrate a method for the synthesis of bimetallic nanoparticles consisting of Pt and Sn. A synthesis strategy is used in which the particular ...

Generation of Scalable, Metallic High-Aspect Ratio Nanocomposites in a Biological Liquid Medium

The goal of this protocol is to describe the synthesis of two novel biocomposites with high-aspect ratio structures. The biocomposites consist of copper and cystine, with either copper nanoparticles (CNPs) or copper sulfate contributing the metallic component. Synthesis is carried out in liquid under biological conditions (37 &#176;C) and the self-assembled composites form after 24 hr. Once formed, these composites are highly stable in both liquid media and in a dried form. The composites scale from the nano- to micro- range in length, and from a few microns to 25 nm in diameter. Field emission scanning electron microscopy with energy dispersive X-ray spectroscopy (EDX) demonstrated that sulfur was present in the NP-derived linear structures, while it was absent from the starting CNP material, thus confirming cystine as the source of sulfur in the final nanocomposites. During synthesis of these linear nano- and micro-composites, a diverse range of lengths of structures is formed in the synthesis vessel. Sonication of the liquid mixture after synthesis was demonstrated to assist in controlling average size of the structures by diminishing the average length with increased time of sonication. Since the formed structures are highly stable, do not agglomerate, and are formed in liquid phase, centrifugation may also be used to assist in concentrating and segregating formed composites.

Here we present a protocol to synthesize novel, high-aspect ratio biocomposites under biological conditions and in liquid media. The biocomposites scale from nanometers to micrometers in diameter and length, respectively. Copper nanoparticles (CNPs) and copper sulfate combined with cystine are the key components for the synthesis.

생물 액체 배지에서 확장 성, 금속 높은 가로 세로 비율 나노 복합 재료의 생성

The goal of this protocol is to describe the synthesis of two novel biocomposites with high-aspect ratio structures. The biocomposites consist of copper ...

Gold Nanoparticle Synthesis

Gold nanoparticles (Au nanoparticles) that are ~12 nm in diameter were synthesized by rapidly injecting a solution of 150 mg (0.15 mmol) of tetrachloroauric acid in 3.0 g (3.7 mmol, 3.6 mL) of oleylamine (technical grade) and 3.0 mL of toluene into a boiling solution of 5.1 g (6.4 mmol, 8.7 mL) of oleylamine in 147 mL of toluene. While boiling and mixing the reaction solution for 2 hours, the color of the reaction mixture changed from clear, to light yellow, to light pink, and then slowly to dark red. The heat was then turned off, and the solution was allowed to gradually cool down to room temperature for 1 hour. The gold nanoparticles were then collected and separated from the solution using a centrifuge and washed three times; by vortexing and dispersing the gold nanoparticles in 10 mL portions of toluene, and then precipitating the gold nanoparticles by adding 40 mL portions of methanol and spinning them in a centrifuge. The solution was then decanted to remove any remaining byproducts and unreacted starting materials. Drying the gold nanoparticles in a vacuum environment produced a solid black pellet; which could be stored for long periods of time (up to one year) for later use, and then redissolved in organic solvents such as toluene.

A protocol for synthesizing ~12 nm diameter gold nanoparticles (Au nanoparticles) in an organic solvent is presented. The gold nanoparticles are capped with oleylamine ligands to prevent agglomeration. The gold nanoparticles are soluble in organic solvents such as toluene.

영가 코어 금속 나노 입자의 생성은 사용 N- (2- 아미노 에틸) -3- aminosilanetriol

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