Name: A Technique to Functionalize and Self-assemble Macroscopic Nanoparticle-ligand Monolayer Films onto Template-free Substrates (Video) | JoVE Journal
Uploaded: 2014-05-09T19:00:00.000+00:00
Duration: 8 min 9 s
Description: Learn a one-pot self-assembly technique to functionalize metallic nanoparticles and create macroscopic monolayer films on template-free substrates. This scalable method enables rapid fabrication for nanotechnology applications.

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5 minutes

This work was supported with funding provided from the Office of Naval Research.&#160;J. Fontana acknowledges the National Research Council for a postdoctoral associateship.

1. Self-assembled Ligand-nanoparticle Monolayers
As an illustrative example of the self-assembly technique, macroscopic, thiol-alkane capped gold nanosphere monolayer films are produced as follows:
<ol>
	<li>Concentrate 15&#160;nm gold nanospheres (commercially available at a number density: 1012 particles/ml) to ~1013 particles/ml&#160;in water.
	<ol>
		<li>Place 15 ml of the dilute nanosphere water suspension into an ultra centrifugal filter (100&#160;K nominal molecular weight limit).</li>
		<li>Centrifuge the filter/vial at 4,500 x g for 2 min&#160;or until only a few ml remain in the filter chamber.</li>
	</ol>
	</li>
	<li>Resuspend the nanosphere in approximately 1 ml of deionized (DI) water such that the nanoparticle concentration is 1013 particles/ml. The suspension is stable for several hours once resuspended in DI water.
	<ol>
		<li>Verify the number density and confirm the nanoparticles have not aggregated. Dilute the concentrated nanoparticle suspension by a factor of 1:10 back to the original concentration by placing 0.150 ml of the suspension into a cuvette (1 cm path length), and to this add 1.35 ml of DI water.</li>
		<li>Place the cuvette into a spectrometer and measure the absorbance spectrum of the suspension and the original suspension. Compare the peak position and full width at half maximum to ensure aggregation has not occurred. The magnitude of the absorbance peaks for both samples should be approximately the same, thus ensuring the concentrated sample is denser by a factor of 10.</li>
	</ol>
	</li>
	<li>In a separate clean 20&#160;ml borosilicate glass vial add 1 ml of tetrahydrofuran (THF).</li>
	<li>Add the thiol-alkane ligands (e.g. 5 ml of 1,6-hexanedithiol and 5 ml of 1-dodecanethiol) to the THF and shake the solution to mix uniformly. Enough ligand should be added to cover at least the entire surface area of the suspended nanoparticles. Excess ligand increases the speed and efficiency of the reaction.</li>
	<li>In a fume hood, pour the contents of the vial containing the gold nanospheres into the vial of THF-ligands.</li>
	<li>Quickly screw on the lid and shake the vial vigorously for 15 sec.</li>
	<li>Remove the lid and set the vial down in the fume hood, Figure 1(a). Depending on the ligands used, domains of gold nanoparticle films quickly form at the air-liquid interface, Figure 1(c). The films will then begin to translate up the sides of the vial, Figure 1(d). Nearly all the nanoparticles are capped with thiol-ligand, removed from the suspension, and transported to the sides of the vial within 1&#160;hr, Figure 1(e).</li>
</ol>
2. Transferring the Monolayers onto Removable Substrates
<ol>
	<li>To transfer the films onto removable glass and silicon wafer substrates: cut the substrates into an area of 12.5 mm x 25.4 mm using a scribing pen/wheel.
	<ol>
		<li>Glass Substrates: clean using an acetone rinse, followed by an isopropyl alcohol rinse, and finally a DI water rinse. Allow the substrates to dry, proceed to section 2.2.</li>
		<li>Silicon Wafer Substrates: in a fume hood prepare Piranha solution (3 parts concentrated sulfuric acid to 1 part 30% hydrogen peroxide, CAUTION: oxidizer, corrosive). Place 15 ml of sulfuric acid into a 20&#160;ml borosilicate glass vial. To this slowly add 5 ml of 30% hydrogen peroxide. Do not cap the vial. Use caution; the mixture is highly exothermic. See reference for more safety information19.</li>
		<li>Carefully submerse the silicon wafer substrates into Piranha solution for 30 min, remove, rinse with DI water and dry with nitrogen.</li>
		<li>As an optional step, the vial used for the nanoparticle ligand exchange and self-assembly can be salinized to force all the nanoparticles onto the glass substrate or silicon wafer instead of the walls of the glass vial, otherwise proceed to section 2.2.</li>
		<li>Fill the glass vial with piranha solution (CAUTION: oxidizer, corrosive), refer to section 2.1.2.</li>
		<li>Allow the vial to soak for 30 min. After 30 min&#160;rinse the vial out with DI water.</li>
		<li>Fill vial with 1% v/v of hexamethyldisilazane in acetone and cap.</li>
		<li>Allow the sealed vial to soak for 24 hr, then rinse with DI water and dry with nitrogen.</li>
	</ol>
	</li>
	<li>Prior to shaking (section 1.6) insert the substrate into the vial. Screw on lid and shake.</li>
	<li>After shaking remove lid and, using tweezers, position the substrate nearly vertical against the vial wall.</li>
	<li>Use a pipette to coat the reaction mixture onto the substrate. The reaction stops when all the organic solvent has evaporated or all the nanoparticle have been removed from the suspension.</li>
</ol>
3. Monolayer Analysis
<ol>
	<li>Estimate the packing efficiency of the nanospheres in the monolayer quickly by observing the transmission and reflective properties of the film. Illuminate the monolayer on glass substrates from behind with a white-light source. With a white light source, a uniform colored film should be observed for high-density nanoparticle monolayer films in transmission and a gold-like reflection observed in reflection, Figure 2.</li>
	<li>Use a spectrometer (see section 1.2.2) to quantify the macroscopic absorbance spectrum from the monolayers, Figure 4. Normalize the absorbance spectrum with a clean glass slide. Mount the monolayer film, on a glass substrate, into the beam path of the spectrometer and collect the absorbance spectrum. 
	Note: The absorbance peak should be significantly red-shifted&#160;several hundred nanometers depending on the ligand used. The quality factor of the absorbance peak should be comparable to the dilute suspension value, but only slightly broadened (Figure 4). If the absorbance peak is very broad or not well defined then the monolayer films are probably of poor quality, proceed to section 3.3 for further characterization.</li>
	<li>Examine the nanoscopic organization of the nanospheres using scanning electron microscopy (SEM) of monolayers transferred onto silicon wafer substrates (see section 2.1.2) as shown in Figure 3. If the films are on glass substrates connect conductive tape to one corner of the film and ground it to the SEM pedestal to prevent charging and allow imaging.</li>
</ol>
4. Efficient Phase Transfer Technique for Organic Soluble Nanoparticles
<ol>
	<li>To use the technique as an efficient means to functionalize the nanoparticles with thiol-ligands, decant the remaining solution from the bottom of the vial after the reaction is complete, section 1.7, and dry the material in the vial under nitrogen.</li>
	<li>Add an organic solvent (e.g. chloroform, toluene) to re-suspend the nanoparticles with nearly 100% particle phase transfer and recovery.</li>
	<li>Repeat section 1.2.1 to ensure the nanoparticles have not aggregated upon re-suspension into the organic solvent. If the absorbance peak is board, relative to the original suspension, sonicate the sample for 15 min&#160;to help redisperse the nanoparticles, Figure 4.</li>
</ol>

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<li>Liu, Z. W., Lee, H., Xiong, Y., Sun, C., Zhang, X. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Far-field+optical+hyperlens+magnifying+sub-diffraction-limited+objects%5BTitle%5D)+AND+%22Science%22%5BJournal%5D)">Far-field optical hyperlens magnifying sub-diffraction-limited objects.</a> Science. 315, 1686-1686 (2007).</li>
<li>Valentine, J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Three-dimensional+optical+metamaterial+with+a+negative+refractive+index%5BTitle%5D)+AND+%22Nature%22%5BJournal%5D)">Three-dimensional optical metamaterial with a negative refractive index.</a> Nature. 455, (2008).</li>
<li>Law, M., Greene, L. E., Johnson, J. C., Saykally, R., Yang, P. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Nanowire+dye-sensitized+solar+cells%5BTitle%5D)+AND+%22Nature+Materials%22%5BJournal%5D)">Nanowire dye-sensitized solar cells.</a> Nature Materials. 4, 455-459 (2005).</li>
<li>Frens, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Controlled+Nucleation+for+Regulation+of+Particle-Size+in+Monodisperse+Gold+Suspensions%5BTitle%5D)+AND+%22Nature-Phys+Sci%22%5BJournal%5D)">Controlled Nucleation for Regulation of Particle-Size in Monodisperse Gold Suspensions.</a> Nature-Phys Sci. 241, 20-22 (1973).</li>
<li>Ye, X., Chen, J., Diroll, B. T., Murray, C. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Tunable+Plasmonic+Coupling+in+Self-Assembled+Binary+Nanocrystal+Superlattices+Studied+by+Correlated+Optical+Microspectrophotometry+and+Electron+Microscopy%5BTitle%5D)+AND+%22Nano+Letters%22%5BJournal%5D)">Tunable Plasmonic Coupling in Self-Assembled Binary Nanocrystal Superlattices Studied by Correlated Optical Microspectrophotometry and Electron Microscopy.</a> Nano Letters. 13, 1291-1297 (2013).</li>
<li>Bigioni, T. P., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Kinetically+driven+self-assembly+of+highly+ordered+nanoparticle+monolayers%5BTitle%5D)+AND+%22Nature+Materials%22%5BJournal%5D)">Kinetically driven self-assembly of highly ordered nanoparticle monolayers.</a> Nature Materials. 5, (2006).</li>
<li>Ng, K. C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Free-Standing+Plasmonic-Nanorod+Super+lattice+Sheets%5BTitle%5D)+AND+%22Acs+Nano%22%5BJournal%5D)">Free-Standing Plasmonic-Nanorod Super lattice Sheets.</a> Acs Nano. 6, 925-934 (2012).</li>
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The authors have nothing to disclose.

This protocol describes a single &#8216;one-pot&#8217; self-assembly technique to create macroscopic nanoparticle-ligand monolayer films using phase transfer, phase separation and surface tension gradients.&#160; The advantage of this technique is that it combines three self-assembly processes into a single, low-cost process; by quickly and efficiently phase transferring the nanoparticles, assembling the particles into monolayers at the air-fluid interface and transporting the monolayer films onto template-free substrate...

The self-assembly of macroscopic nanoparticle films has attracted great attention for their unique properties determined from the geometry and composition of the elements5 and may lead to of a wide range of optical, electronic and chemical applications6-14. To self-assemble such films metallic nanoparticles capped with ligands must be packed into high density, monolayers. However several assembly issues need to be addressed to advance the development of such materials.
First, surfactant stabilized metallic nanoparticles are typically synthesized by wet-chemistry methods in dilute suspensions15. To prevent aggregation and to control the interparticle spacing of the nanoparticles in the films, the nanoparticles need to be capped with ligand shells. After the nanoparticles have been functionalized with ligands the nanoparticles typically remain in relatively dilute suspensions.&#160;A technique is then needed to self-assemble the nanoparticles into macroscopic, high-density, monolayer films16,17.
Cheng et al.18 phase transferred gold nanorods using thiolated polystyrene in a water-tetrahydrofuran suspension.&#160; The nanorods where then re-suspended in chloroform and a drop was placed at an air-water interface and evaporated slowly, forming monolayer films. Bigioni et al.17 created macroscopic monolayers of dodecanethiol capped gold nanospheres using excess ligand and rapid solvent evaporation, but the nanospheres needed to be phase transferred prior to self-assembling.&#160;
Once the monolayer films are formed they typically need to be transported onto a substrate.&#160; Mayya et al.3 confined nanospheres at a water-toluene interface and transferred them onto template-free substrates using surface tension gradients. Similarly, Johnson et al.4&#160;suspended silver nanospheres in excess ligand and then translated the nanoparticles up the walls of the vial using surface tension gradients from two immiscible fluids. While assembly techniques exist to address each of these issues the need for more efficient techniques is needed to aid in the development of large-scale nanoparticle film production.
Here we demonstrate a straightforward and robust technique that combines the three self-assembly issues described above in to a single &#8216;one-pot&#8217; technique, shown in Figure 1. A water miscible organic solvent (e.g. tetrahydrofuran, dimeythl sulfoxide), is used to first quickly and efficiently functionalize thiol-ligands (e.g. thiol-alkane, thiol-ene, thiol-phenol) onto the nanoparticles (e.g. gold nanospheres, nanorods, etc.). The mixture then drives&#160;self-assembly of the nanoparticles into macroscopic, high-density, monolayer films at the air-fluid interface using phase separation.&#160; Finally, monolayer films of nanoparticles form onto template-free substrates using surface tension gradients from the water/organic solvent mixture, Figure 2 and Figure 3.

<table><tbody><tr><td>1,6-hexanedithiol</td><td>Sigma</td><td>H12005-5G</td><td></td></tr><tr><td>1-dodecanethiol</td><td>Sigma</td><td>471364-100ML</td><td></td></tr><tr><td>20 ml liquid scintillation vials</td><td>Sigma</td><td>Z253081-1PAK</td><td></td></tr><tr><td>Acetone</td><td>Sigma</td><td>650501-1L</td><td></td></tr><tr><td>Amicon ultra-15 centrifugal filter</td><td>Millipore</td><td>100K</td><td></td></tr><tr><td>Centrifuge</td><td>Sorvall</td><td>RC5B</td><td></td></tr><tr><td>Centrifuge</td><td>Eppendorf</td><td>5810R</td><td></td></tr><tr><td>Deionized water</td><td>In-house</td><td>N/A</td><td></td></tr><tr><td>Glass slides</td><td>Sigma</td><td>CLS294875X25-72EA</td><td></td></tr><tr><td>15 nm gold nanospheres</td><td>Ted Pella, Inc</td><td>15703-1</td><td></td></tr><tr><td>Hexamethyldisilazane</td><td>Sigma</td><td>52619-50ML</td><td></td></tr><tr><td>Hydrogen peroxide (30%)</td><td>Sigma</td><td>216763-100ML</td><td></td></tr><tr><td>Scanning electron microscope</td><td>Carl Zeiss</td><td>Model 55</td><td></td></tr><tr><td>Polished silicon wafer</td><td>Sun Edison</td><td>N/A</td><td></td></tr><tr><td>spectrometer</td><td>OceanOptics</td><td>USB4000-VIS-NIR</td><td></td></tr><tr><td>Sulfuric acid</td><td>Fisher</td><td>A300-212</td><td></td></tr><tr><td>Tetrahydrofuran</td><td>Sigma</td><td>401757-100ML</td><td></td></tr></tbody></table>

a technique to functionalize and self-assemble macroscopic nanoparticle-ligand monolayer films onto template-free substrates

A Technique to Functionalize and Self-assemble Macroscopic Nanoparticle-ligand Monolayer Films onto Template-free Substrates

This protocol describes a self-assembly technique to create macroscopic monolayer films composed of ligand-coated nanoparticles1,2. The simple, robust and scalable technique efficiently functionalizes metallic nanoparticles with thiol-ligands in a miscible water/organic solvent mixture allowing for rapid grafting of thiol groups onto the gold nanoparticle surface. The hydrophobic ligands on the nanoparticles then quickly phase separate the nanoparticles from the aqueous based suspension and confine them to the air-fluid interface. This drives the ligand-capped nanoparticles to form monolayer domains at the air-fluid interface.&#160; The use of water-miscible organic solvents is important as it enables the transport of the nanoparticles from the interface onto template-free substrates.&#160; The flow is mediated by a surface tension gradient3,4 and creates macroscopic, high-density, monolayer nanoparticle-ligand films.&#160; This self-assembly technique may be generalized to include the use of particles of different compositions, size, and shape and may lead to an efficient assembly method to produce low-cost, macroscopic, high-density, monolayer nanoparticle films for wide-spread applications.

Figure 1(a) shows a suspension of gold nanospheres, thiol-alkane ligands, tetrahydrofuran and water in a glass vial immediately after mixing. A schematic of the three main self-assembly stages, phase transfer, phase separation, and surface tension gradient mediated film transport is shown in Figure 1(b) as an expanded view at the air-fluid interface near the side of the vial.
The thiol groups on the ligands rapidly bond to the gold nanospheres after mixing, di...

A simple, robust and scalable technique to functionalize and self-assemble macroscopic nanoparticle-ligand monolayer films onto template-free substrates is described in this protocol.

This protocol describes a self-assembly technique to create macroscopic monolayer films composed of ligand-coated nanoparticles1,2. The simple, robust and ...

The overall goal of this procedure is to develop macroscopic, nanoparticle, ligand, monolayer films. This is accomplished by using a single one-pot self-assembly technique. First metallic nanoparticles, a rapidly functionalized with ligands in a water tetrahedran or THF solvent.Next, the ligand kept nanoparticles phase separate to the air solvent interface. Finally, the nanoparticles are transported onto template free substrates using surface tension gradients, self assembling into macroscopic nanoparticle, ligand monolayer films. Ultimately, this procedure provides a simple, robust, and scalable technique to functionalize and self-assemble macroscopic nanoparticle, ligand monolayer films onto template free substrates.The main advantage of this technique over other interfacial assembly methods is the rapid and efficient nanoparticle functionalization and self-assembly into macroscopic monolayer films. Though this method can provide insight into the organic inorganic interface at do nanoscale level, it can also be applied to a wide variety of application such as metamaterials, photovoltaic, and molecular sensors. To begin concentrate commercially available 15 nanometer gold nanospheres by placing 15 milliliters of the dilute nanosphere of water suspension into an ultra centrifugal filter.Then centrifuge the unit at 4, 500 Gs for two minutes or until only a few microliters remain in the filter chamber. Re suspend the nanosphere in 1.5 milliliters of deionized or DI water or such that the nanoparticle concentration is approximately 10 to the 13th particles per milliliter. The suspension is stable for several hours.Once resuspended in di water, to verify the number density and confirm the nanoparticles have not aggregated first pipette 150 microliters of the suspension into a vet. Also dilute the concentrated nanoparticle suspension with 1.35 milliliters of di water. Next, place the vet into an ultraviolet visible spectrometer and measure the absorbent spectrum of the prepared suspension as well as that of the original suspension.Compare the peak position in full width at half maximum to ensure aggregation has not occurred. The magnitude of the absorbance peaks for both samples should be approximately the same. Thus ensuring the concentrated sample is denser by a factor of 10 in a separate clean 20 milliliter bur silicate glass file at one milliliter of tetra hydro furin.Next, add thiol alkane ligands to the THF and shake. The solution to mix uniformly enough. Ligand should be added to cover at least the entire surface area of the suspended nanoparticles.Excess ligand increases the speed and deficiency of the reaction in a fume hood. Place one milliliter from the vial containing the gold nanospheres into the vial of THF ligands. Quickly screw on the lid and shake the vial vigorously for 15 seconds.Remove the lid and set the vial down. In the fume hood, Depending on the ligands, used domains of golden nanoparticles quickly form at the air liquid interface. The films then begin to translate up the side of the vial.Nearly all the nanoparticles have been capped with thal ligands removed from suspension and transported to the side of the vials within an hour. To transfer the films onto removable glass substrates, cut the substrates into an area of 12.5 by 25.4 millimeters using a scribing pen or wheel for glass substrates clean, using an acetone rinse, followed by an isopropyl alcohol rinse. And finally, a di water rinse.Before allowing the substrates to dry, see the text protocol for preparation of silicon wafers. Next, insert the substrate into the previously prepared vial of nanospheres and ligands. Screw on the lid and shake.After shaking, remove the lid using tweezers. Position the substrate nearly vertical against the vial wall. Then use a pipette to coat the reaction mixture onto the substrate.The reaction stops when all the organic solvent has evaporated or all the nanoparticles have been removed from the suspension. Estimate the packing efficiency of the nanospheres in the monolayer by observing the transmission and reflective properties of the film. Illuminate the monolayer on glass substrates from behind with a white light source.A uniform colored film should be observed for high density nanoparticle, monolayer films in transmission and a gold like reflection observed in reflection. Next, use a spectrometer to quantify the macroscopic absorbent spectrum from the monolayers. As before, normalize the absorbent spectrum with a clean glass slide.Then mount the monolayer film on a glass substrate in the beam path of the spectrometer and collect the absorbent spectrum. The absorbent peak should be significantly redshifted several hundred nanometers depending on the ligand used. If the absorbent peak is very broad or not well-defined, then the monolayer films are probably of poor quality.To use the technique as an efficient means to functionalize the nanoparticles with thal ligands. Decant the remaining from the bottom of the vial. After the reaction is complete, then dry the material in the vial under nitrogen.Add an organic solvent to resuspend the nanoparticles with nearly 100%particle phase transfer and recovery ensure the nanoparticles have not aggregated upon resuspension into the organic solvent as before, if the absorbence peak is broad relative to the original suspension, sonicate the sample for 15 minutes to help re disperse the nanoparticles. A thi alkane kept 15 nanometer gold nanosphere monolayer film on a glass substrate is observed partially reflecting light, signifying the high volume fraction of nanospheres and transmitting light, demonstrating the preservation of the plasma and resonances Uniformity and optical clarity shown here are false colored scanning electron microscopy images of athe acan capped 15 nanometer gold nanosphere monolayer film on a silicon wafer substrate. The edge of the film demonstrates that the films are monolayers and that the nanospheres pack into amorous domains at microscopic length scales.At nanoscopic length scales. The films contain hexagon close, packed domains as demonstrated by the Fourier transform of the image.Shown. Here is the normalized experimental absorbance from a monolayer film consisting of thiol acan ca 15 nanometer gold nanospheres on a glass substrate.A suspension of 15 nanometer gold nanospheres in water and phase transferred into chloroform Once mastered. This technique can be done in less than an hour if performed properly. After washing this video, you should have a good understanding of how to efficiently functionalize and self assemble metallic nanoparticles into microscopic monolith films.

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We describe a method for the fabrication of large-area (up to 13 cm diameter) and ultrathin (as thin as 8 nm) polymer films. Instead of using a sacrificial interlayer to delaminate the film from its substrate, we use a self-limiting surface treatment suitable for arbitrarily large areas.

Fabrication of Large-area Free-standing Ultrathin Polymer Films

In this paper we describe the interfacial synthesis of conjugated microporous polymers (CMP) on sacrificial substrates, and the dissolution of the substrate for the preparation of freestanding CMP nanomembranes. In addition, we will describe how the fragile nanomembranes can be transferred to other substrates.

Layer-by-layer Synthesis and Transfer of Freestanding Conjugated Microporous Polymer Nanomembranes

Nanoscaled sea-island surfaces composed of thermoresponsive block copolymers were fabricated by the Langmuir-Schaefer method for controlling spontaneous cell adhesion and detachment. Both the preparation of the surface and the adhesion and detachment of cells on the surface were visualized.

Preparation of Thermoresponsive Nanostructured Surfaces for Tissue Engineering

A protocol for producing a large area of nanopatterned substrate from small nanopatterned molds for study of nanotopographical modulation of cell behavior is presented.

Expanding Nanopatterned Substrates Using Stitch Technique for Nanotopographical Modulation of Cell Behavior

We present a protocol to functionalize glass with nanometric protein patches surrounded by a fluid lipid bilayer. These substrates are compatible with advanced optical microscopy and are expected to serve as platform for cell adhesion and migration studies.

Ligand Nano-cluster Arrays in a Supported Lipid Bilayer

We demonstrate the fabrication of periodic gold nanocup arrays using colloidal lithographic techniques and discuss the importance of nanoplasmonic films.

Fabrication of Periodic Gold Nanocup Arrays Using Colloidal Lithography

Surface fabrication methods for patterned deposition of nanometer thick brushes or micron thick, crosslinked films of an azlactone block co-polymer are reported. Critical experimental steps, representative results, and limitations of each method are discussed. These methods are useful for creating functional interfaces with tailored physical features and tunable surface reactivity.

Fabricating Reactive Surfaces with Brush-like and Crosslinked Films of Azlactone-Functionalized Block Co-Polymers

This protocol details a novel nano-manufacturing technique that can be used to make controllable and customizable nanoparticle films over large areas based on the self-assembly of dewetting of capped metal films.

Large Area Substrate-Based Nanofabrication of Controllable and Customizable Gold Nanoparticles Via Capped Dewetting

A protocol for the synthesis and characterization of self-assembled metal-organic framework monolayers is provided using polymer-grafted, metal-organic framework (MOF) crystals. The procedure shows that polymer-grafted MOF particles can be self-assembled at an air-water interface resulting in well-formed, free-standing, monolayer structures as evidenced by scanning electron microscopy imaging.

Synthesis and Characterization of Self-Assembled Metal-Organic Framework Monolayers Using Polymer-Coated Particles

Learn a one-pot self-assembly technique to functionalize metallic nanoparticles and create macroscopic monolayer films on template-free substrates. This scalable method enables rapid fabrication for nanotechnology applications.

A Technique to Functionalize and Self-assemble Macroscopic Nanoparticle-ligand Monolayer Films onto Template-free Substrates

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