Name: Synthesis of Graphene Nanofluids with Controllable Flake Size Distributions (Video) | JoVE Journal
Uploaded: 2019-07-17T13:00:00.000+00:00
Duration: 7 min 32 s
Description: Learn to synthesize graphene nanofluids with controllable flake size distributions using exfoliation and centrifugation processes. This method enables precise control over size parameters for advanced materials applications.

ai_agent_IP

ai_agent

maintenance

instantTrialDurationMinutes

isBiopharma

enableNewMyJoveSectionDesign

educationFeatures

seoMetaApi

ai_copilot_institution_blacklist

ai_chat_institution_blacklist

freeAccessWindow

ssoRoleCapture

scheduledMaintenanceBanner

joveLabsFeatures

disable_autoplay_for_bots

extended_trial_duration

5 minutes

This work was supported by the National Nature Science Foundation of China (Grant&nbsp;No. 21776095), the Guangzhou Science and Technology Key Program (Grant&nbsp;No. 201804020048), and Guangdong Key Laboratory of Clean Energy Technology (Grant No. 2008A060301002). We thank LetPub (www.letpub.com) for its linguistic assistance during the preparation of this manuscript.

1. Exfoliation of graphite in a liquid phase
<ol>
	<li>Preparation of reagents
	<ol>
		<li>In a dry clean flat-bottom flask, add 20 g of polyvinyl alcohol (PVA), and then add 1,000 mL of distilled water. 
		NOTE: If the suspension was not processed to satisfaction, the step could be repeated to obtain an additional suspension.</li>
		<li>Gently swirl the flask until the PVA fully dissolves. 
		CAUTION: PVA is harmful to humans; thus, protective gloves and surgical masks should be used.</li>
		<li>Add 50 g of graphite powder to the flat-bottom flask, and gently swirl the flask until the graphite powder fully disperses in the suspension.</li>
		<li>Transfer 500 mL of the resulting suspension to a 500 mL beaker.</li>
		<li>Place the beaker under a shear mixer, positioning the beaker near the center of the mixing vessel to prevent the formation of a vortex. 
		NOTE: All chemical reagents used are of analytical grade.</li>
	</ol>
	</li>
	<li>Equipment setup
	<ol>
		<li>Lower the mixing head to its lowest position (30 mm from the base plane).</li>
		<li>Make a water bath by filling a 5,000 mL beaker with room temperature (25 °C) water and position the 500 mL beaker in the bath. Change the water every 30 min.</li>
	</ol>
	</li>
	<li>Exfoliation
	<ol>
		<li>Start the mixer and increase the speed gradually to 4,500 rpm; mix at this speed for 120 min.</li>
		<li>Perform the exfoliation step five times for five predetermined times: 40 min, 60 min, 80 min, 100 min, and 120 min. The mixing time determines the lower lateral size limit of the graphene nanoflakes.</li>
		<li>Collect the suspensions after each exfoliation step. Each exfoliation step will generate a 500 mL suspension. Label each suspension with the exfoliation time for further treatment.</li>
		<li>Centrifuge the collected suspension at 140 x g for 45 min to remove the unexfoliated graphite.</li>
		<li>Collect the top 80% of the supernatant from each centrifuge tube for an additional centrifugation step.</li>
	</ol>
	</li>
</ol>
2. Centrifugation
<ol>
	<li>Centrifuge the resulting suspension at 8,951 x g for 45 min.</li>
	<li>Collect the upper 50% of the supernatant in the centrifuge tube, and label the sample with a number.</li>
	<li>Recycle the sediment on the bottom of the centrifuge tube from step 2.2. Add the PVA/water reagent prepared in step 1.1.1 to the sediments and shake the tube vigorously by hand until the sediment is well dispersed in the suspension.</li>
	<li>Centrifuge the suspension at 8,951 x g for 45 min; collect the upper 80% for further measurements.</li>
	<li>Repeat the abovementioned centrifugation step four times with four different centrifugation speeds: 5,035 x g, 2,238 x g, 560 x g, and 140 x g. The centrifugation speed determines the upper lateral size limit of the graphene nanoflakes. 
	NOTE: The protocol can be paused here.</li>
</ol>
3. Concentration measurements of the resulting nanofluids
<ol>
	<li>Obtain absorption spectra at a wavelength of 660 nm using ultraviolet-visible (UV-Vis) spectroscopy.
	<ol>
		<li>Use the PVA/water solution prepared in step 1.1.1 to calibrate a UV-Vis spectrometer; set the PVA/water concentrations to 0%.</li>
		<li>Add the PVA/water suspension to a dry clean sample cell with a path length of 10 mm and obtain a readout using the manufacturer’s software. Click the obtain button to get the measurement results graph and save the results.</li>
		<li>Repeat step 3.1.2 for each of the different samples prepared in step 2.5. 
		NOTE: The sample cell must be cleaned carefully with distilled water and dried before use each time.</li>
	</ol>
	</li>
	<li>Determine the graphene weight in the resulting suspension.
	<ol>
		<li>Vacuum filter the 100 mL sample suspension using a nylon membrane with a pore size of 0.2 µm.</li>
		<li>Wash the membrane film with approximately 1,000 mL of water; repeat this step three times until all the solids are washed from the membrane.</li>
		<li>Determine the washed water mass with a high-precision microbalance to obtain the weight of the solids in the 100 mL suspension. 
		NOTE: The weights include both the weight of the graphene nanoflakes and the PVA polymers.</li>
		<li>Analyze the water with thermogravimetric analysis (TGA)18 to determine the PVA concentration.</li>
		<li>Calculate the mean extinction coefficient values of the PVA-stabilized system: 
		<img alt="Absorbance formula A=εCGl, Beer-Lambert law, diagram for spectroscopy analysis." src="/files/ftp_upload/59740/59740equ01.jpg" data-altupdatedat="1788282455000" data-alt="Equation 1"> 
		where A is the absorbance measured at 660 nm using UV-Vis spectroscopy, and I is the path length travelled by the UV light during the measurement; the relationship between the absorbance A and the graphene concentration CG is linear. The extinction coefficient ε is the slope of the curve plotted for the absorbance A as a function of the graphene concentration CG. When the extinction coefficient ε is determined, CG can be determined by the absorbance A.</li>
	</ol>
	</li>
</ol>
4. Adjusting the concentration of resulting nanofluids
<ol>
	<li>Vacuum-filter the suspensions using a nylon membrane with a pore size of 0.2 µm.</li>
	<li>Dry the membrane at room temperature for over 12 h.</li>
	<li>Subsequently, rinse the film with hot deionized water.</li>
	<li>Dry the deionized water under a vacuum for 24 h to obtain the graphene nanosheets. 
	NOTE: The production rate of graphene is approximately 1 mg/mL. If the desired concentration is lower than this, then it is easy to obtain it only by adding PVA/water. If the desired concentration is higher than 1%, then the drying process is necessary. Here, we demonstrate a condition with a desired concentration of 2%.</li>
	<li>Add the PVA/water solution or graphene nanosheets to adjust the concentration.</li>
	<li>If the desired concentration is less than the production rate, add the PVA/water solution prepared in step 1.1.1 to obtain the desired concentration.</li>
</ol>
5. Measuring the size distributions with dynamic light scattering
<ol>
	<li>Turn on the nanoparticle analyzer and adjust the detector to C label. Place the sample suspension on the test panel.</li>
	<li>Open the correlator control window software.</li>
	<li>Click Non-Negative Constrained least square: Multiple Pass in the menu.</li>
	<li>Set the elapsed time to 2 min.</li>
	<li>Select water as the solvent type.</li>
	<li>Change the diameter of the detector to 100 nm.</li>
	<li>Click the test button to obtain the readout and save the results.</li>
	<li>Repeat steps 5.1-5.7 for each of the samples prepared after step 4.</li>
</ol>

<ol><li>Sadeghinezhad, E., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((A+comprehensive+review+on+graphene+nanofluids%3A+Recent+research%2C+development+and+applications%5BTitle%5D)+AND+%22Energy+Conversion+and+Management%22%5BJournal%5D)">A comprehensive review on graphene nanofluids: Recent research, development and applications.</a> Energy Conversion and Management. 111, 466-487 (2016).</li>
<li>Wang, W., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Highly+Efficient+Production+of+Graphene+by+an+Ultrasound+Coupled+with+a+Shear+Mixer+in+Supercritical+CO2%5BTitle%5D)+AND+%22Industrial+%26+Engineering+Chemistry+Research%22%5BJournal%5D)">Highly Efficient Production of Graphene by an Ultrasound Coupled with a Shear Mixer in Supercritical CO2.</a> Industrial & Engineering Chemistry Research. 57 (49), 16701-16708 (2018).</li>
<li>Cao, H. Y., Guo, Z. X., Xiang, H., Gong, X. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Layer+and+size+dependence+of+thermal+conductivity+in+multilayer+graphene+nanoribbons%5BTitle%5D)+AND+%22Physics+Letters+A%22%5BJournal%5D)">Layer and size dependence of thermal conductivity in multilayer graphene nanoribbons.</a> Physics Letters A. 376 (4), 525-528 (2012).</li>
<li>Yang, N., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Design+and+adjustment+of+the+graphene+work+function+via+size%2C+modification%2C+defects%2C+and+doping%3A+a+first-principle+theory+study%5BTitle%5D)+AND+%22Nanoscale+Research+Letters%22%5BJournal%5D)">Design and adjustment of the graphene work function via size, modification, defects, and doping: a first-principle theory study.</a> Nanoscale Research Letters. 12, (2017).</li>
<li>Khan, U., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Size+selection+of+dispersed%2C+exfoliated+graphene+flakes+by+controlled+centrifugation%5BTitle%5D)+AND+%22Carbon%22%5BJournal%5D)">Size selection of dispersed, exfoliated graphene flakes by controlled centrifugation.</a> Carbon. 50 (2), 470-475 (2012).</li>
<li>Smith, R. J., King, P. J., Wirtz, C., Duesberg, G. S., Coleman, J. N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Lateral+size+selection+of+surfactant-stabilised+graphene+flakes+using+size+exclusion+chromatography%5BTitle%5D)+AND+%22Chemical+Physics+Letters%22%5BJournal%5D)">Lateral size selection of surfactant-stabilised graphene flakes using size exclusion chromatography.</a> Chemical Physics Letters. 531, 169-172 (2012).</li>
<li>Galvin, K. P., Pratten, S. J., Nicol, S. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Dense+medium+separation+using+a+teetered+bed+separator%5BTitle%5D)+AND+%22Minerals+Engineering%22%5BJournal%5D)">Dense medium separation using a teetered bed separator.</a> Minerals Engineering. 12 (9), 1059-1081 (1999).</li>
<li>Cai, C. J., Sang, N. N., Shen, Z. G., Zhao, X. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Facile+and+size-controllable+preparation+of+graphene+oxide+nanosheets+using+high+shear+method+and+ultrasonic+method%5BTitle%5D)+AND+%22Journal+of+Experimental+Nanoscience%22%5BJournal%5D)">Facile and size-controllable preparation of graphene oxide nanosheets using high shear method and ultrasonic method.</a> Journal of Experimental Nanoscience. 12 (1), 247-262 (2017).</li>
<li>Chen, L. X., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Oriented+graphene+nanoribbons+embedded+in+hexagonal+boron+nitride+trenches%5BTitle%5D)+AND+%22Nature+Communications%22%5BJournal%5D)">Oriented graphene nanoribbons embedded in hexagonal boron nitride trenches.</a> Nature Communications. 8, (2017).</li>
<li>Fan, T. J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Controllable+size-selective+method+to+prepare+graphene+quantum+dots+from+graphene+oxide%5BTitle%5D)+AND+%22Nanoscale+Research+Letters%22%5BJournal%5D)">Controllable size-selective method to prepare graphene quantum dots from graphene oxide.</a> Nanoscale Research Letters. 10, 1-8 (2015).</li>
<li>Oikonomou, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Scalable+bottom-up+assembly+of+suspended+carbon+nanotube+and+graphene+devices+by+dielectrophoresis%5BTitle%5D)+AND+%22Physica+Status+Solidi-Rapid+Research+Letters%22%5BJournal%5D)">Scalable bottom-up assembly of suspended carbon nanotube and graphene devices by dielectrophoresis.</a> Physica Status Solidi-Rapid Research Letters. 9 (9), 539-543 (2015).</li>
<li>Liu, Y., Zhang, D., Pang, S. W., Liu, Y. Y., Shang, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Size+separation+of+graphene+oxide+using+preparative+free-flow+electrophoresis%5BTitle%5D)+AND+%22Journal+of+Separation+Science%22%5BJournal%5D)">Size separation of graphene oxide using preparative free-flow electrophoresis.</a> Journal of Separation Science. 38 (1), 157-163 (2015).</li>
<li>Cui, C. N., Huang, J. T., Huang, J. H., Chen, G. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Size+separation+of+mechanically+exfoliated+graphene+sheets+by+electrophoresis%5BTitle%5D)+AND+%22Electrochimica+Acta%22%5BJournal%5D)">Size separation of mechanically exfoliated graphene sheets by electrophoresis.</a> Electrochimica Acta. 258, 793-799 (2017).</li>
<li>Sun, Z. Y., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((High-yield+exfoliation+of+graphite+in+acrylate+polymers%3A+A+stable+few-layer+graphene+nanofluid+with+enhanced+thermal+conductivity%5BTitle%5D)+AND+%22Carbon%22%5BJournal%5D)">High-yield exfoliation of graphite in acrylate polymers: A stable few-layer graphene nanofluid with enhanced thermal conductivity.</a> Carbon. 64, 288-294 (2013).</li>
<li>Sun, Z. Y., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Amine-based+solvents+for+exfoliating+graphite+to+graphene+outperform+the+dispersing+capacity+of+N-methyl-pyrrolidone+and+surfactants%5BTitle%5D)+AND+%22Chemical+Communications%22%5BJournal%5D)">Amine-based solvents for exfoliating graphite to graphene outperform the dispersing capacity of N-methyl-pyrrolidone and surfactants.</a> Chemical Communications. 50 (72), 10382-10385 (2014).</li>
<li>Du, B. L., Jian, Q. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Size+controllable+synthesis+of+graphene+water+nanofluid+with+enhanced+stability%5BTitle%5D)+AND+%22Fullerenes+Nanotubes+and+Carbon+Nanostructures%22%5BJournal%5D)">Size controllable synthesis of graphene water nanofluid with enhanced stability.</a> Fullerenes Nanotubes and Carbon Nanostructures. 27 (1), 87-96 (2019).</li>
<li>Tao, H. C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Scalable+exfoliation+and+dispersion+of+two-dimensional+materials+-+an+update%5BTitle%5D)+AND+%22Physical+Chemistry+Chemical+Physics%22%5BJournal%5D)">Scalable exfoliation and dispersion of two-dimensional materials - an update.</a> Physical Chemistry Chemical Physics. 19 (2), 921-960 (2017).</li>
<li>Phiri, J., Gane, P., Maloney, T. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((High-concentration+shear-exfoliated+colloidal+dispersion+of+surfactant-polymer-stabilized+few-layer+graphene+sheets%5BTitle%5D)+AND+%22Journal+of+Materials+Science%22%5BJournal%5D)">High-concentration shear-exfoliated colloidal dispersion of surfactant-polymer-stabilized few-layer graphene sheets.</a> Journal of Materials Science. 52 (13), 8321-8337 (2017).</li>
</ol>

The authors have nothing to disclose.

We have proposed a methodology for synthesizing graphene nanofluids with controllable flake size distributions. The method combines two procedures: exfoliation and centrifugation. Exfoliation controls the lower size limit of the nanoparticles, and centrifugation controls the upper size limit of the nanoparticles.
Although we employed liquid-phase exfoliation of graphite to produce graphene nanoparticles, the following modifications to the protocol should be considered. Additional exfoliation p...

Traditional methods used to synthesize graphene nanofluids often use sonication to disperse graphene powder1 in fluids, and sonication has been proven to change the size distribution of graphene nanoparticles2. Since the thermal conductivity of graphene depends on the flake length3,4, the synthesis of graphene nanofluids with controllable flake size distributions is vital to heat-transfer applications. Controlled centrifugation has been successfully applied to liquid exfoliated graphene dispersions to separate suspensions into fractions with different mean flake sizes5,6. Different terminal velocities used in centrifugation lead to different critical settling particle sizes7. The terminal velocity could be used to eliminate large graphene nanoparticles8.
Recently, size-controllable methods used to synthesize graphene via liquid-phase exfoliation have been introduced to overcome the fundamental problems encountered by conventional methods9,10,11,12,13. Liquid phase exfoliation of graphite has been proven to be an effective way to produce graphene suspensions14,15,16, and the underlying mechanism shows that the process parameters are related to the lower limits of the graphene nanoparticles size distributions. The graphene nanofluids were synthesized by the liquid exfoliation of the graphite with the help of surfactants17.While the lower limits of the graphene nanoparticle size distribution could be controlled by adjusting the parameters during the exfoliation, less attention is paid to the upper limits of the graphene nanoparticle size distribution.
The goal of this work is to develop a protocol that can be used to synthesize graphene nanofluids with controllable flake size distributions. Because exfoliation is responsible only for the lower size limit of the resulting graphene nanoflakes, additional centrifugation is introduced to control the upper size limit of the resulting graphene nanoflakes. However, the proposed method is not specific to graphene and could be appropriate for any other layered compounds that cannot be synthesized using traditional methods.

<table><tbody><tr><td>Beaker</td><td>China Jiangsu Mingtai Education Equipments Co., Ltd.</td><td>500 mL</td><td></td></tr><tr><td>Beaker</td><td>China Jiangsu Mingtai Education Equipments Co., Ltd.</td><td>5000 mL</td><td></td></tr><tr><td>Deionized water</td><td>Guangzhou Yafei Water Treatment Equipment Co., Ltd.</td><td></td><td>analytical grade</td></tr><tr><td>Electronic balance</td><td>Shanghai Puchun Co., Ltd.</td><td>JEa10001</td><td></td></tr><tr><td>Filter membrane</td><td>China Tianjin Jinteng Experiment Equipments Co., Ltd.</td><td>0.2 micron</td><td></td></tr><tr><td>Graphite powder</td><td>Tianjin Dengke chemical reagent Co., Ltd.</td><td></td><td>analytical grade</td></tr><tr><td>Hand gloves</td><td>China Jiangsu Mingtai Education Equipments Co., Ltd.</td><td></td><td></td></tr><tr><td>Laboratory shear mixer</td><td>Shanghai Specimen and Model Factory</td><td>jrj-300</td><td></td></tr><tr><td>Long neck flat bottom flask</td><td>China Jiangsu Mingtai Education Equipments Co., Ltd.</td><td>1000 ml</td><td></td></tr><tr><td>Nanoparticle analyzer</td><td>HORIBA, Ltd.</td><td>SZ-100Z</td><td></td></tr><tr><td>PVA</td><td>Shanghai Yingjia Industrial Development Co., Ltd.</td><td>1788</td><td>analytical grade</td></tr><tr><td>Raman spectrophotometer</td><td>HORIBA, Ltd.</td><td>Horiba LabRam 2</td><td></td></tr><tr><td>Scanning electron microscope</td><td>Zeiss Co., Ltd.</td><td>LEO1530VP</td><td>SEM</td></tr><tr><td>Surgical mask</td><td>China Jiangsu Mingtai Education Equipments Co., Ltd.</td><td>for one-time use</td><td></td></tr><tr><td>Thermal Gravimetric Analyzer</td><td>German NETZSCH Co., Ltd.</td><td>NETZSCH TG 209 F1 Libra</td><td>TGA analysis</td></tr><tr><td>Transmission electron microscope</td><td>Japan Electron Optics Laboratory Co., Ltd.</td><td>JEM-1400plus</td><td>TEM</td></tr><tr><td>UV-Vis spectrophotometer</td><td>Agilent Technologies, Inc.+BB2:B18</td><td>Varian Cary 60</td><td></td></tr><tr><td></td><td></td><td></td><td></td></tr><tr><td colspan="4">&lt;p class=&quot;jove_content&quot;&gt;Try the professional online HTML editor&lt;/p&gt;</td></tr></tbody></table>

synthesis of graphene nanofluids with controllable flake size distributions

Synthesis of Graphene Nanofluids with Controllable Flake Size Distributions

A method for synthesizing graphene nanofluids with controllable flake size distributions is presented. Graphene nanoflakes can be obtained by the exfoliation of graphite in the liquid phase, and the exfoliation time is used to control the lower limits of the graphene nanoflake size distributions. Centrifugation is successfully used to control the upper limits of the nanoparticle size distributions. The objective of this work is to combine exfoliation and centrifugation to control the graphene nanoflake size distributions in the resulting suspensions.

The existence of graphene nanosheets can be validated by various characteristic techniques. Figure 1 shows the results of the UV-Vis measurement for the various flake size distributions produced by the abovementioned protocol. The spectra absorbance peak obtained at a wavelength of 270 nm is evidence of the graphene flakes. Different absorbances correspond to different concentrations. The lowest absorbance observed corresponds to the highest centrifugation speed. The spectra strongly confirm...

A method for synthesizing graphene nanofluids with controllable flake size distributions is presented.

A method for synthesizing graphene nanofluids with controllable flake size distributions is presented. Graphene nanoflakes can be obtained by the ...

synthesis-graphene-nanofluids-with-controllable-flake-size

Research

JoVE Journal

Chemistry

Anodic arc discharge is one of the most practical and efficient methods to synthesize various carbon nanostructures. To increase the arc controllability and flexibility, a non-uniform magnetic field was introduced to process the one-step synthesis of large-scale graphene flakes and high-purity single-walled carbon nanotubes.

Simultaneous Synthesis of Single-walled Carbon Nanotubes and Graphene in a Magnetically-enhanced Arc Plasma

Millifluidic devices are utilized for controlled synthesis of nanomaterials, time-resolved analysis of reaction mechanisms and continuous flow catalysis.

Millifluidics for Chemical Synthesis and Time-resolved Mechanistic Studies

This video method describes the synthesis of high surface area, monolithic 3D graphene-based materials derived from polymer precursors as well as single layer graphene oxide.

Synthesis and Functionalization of 3D Nano-graphene Materials: Graphene Aerogels and Graphene Macro Assemblies

A protocol for the liquid exfoliation of layered materials to nanosheets, their size selection and size measurement by microscopic and spectroscopic techniques is presented.

Preparation of Liquid-exfoliated Transition Metal Dichalcogenide Nanosheets with Controlled Size and Thickness: A State of the Art Protocol

This article describes a process for tuning the size and crosslinking density of covalently crosslinked nanoparticles from linear polyesters containing pendant functionality. By tailoring synthesis parameters (polymer molecular weight, pendant functionality incorporation, and crosslinker equivalents), a desired nanoparticle size and crosslinking density can be achieved for drug delivery applications.

Nanosponge Tunability in Size and Crosslinking Density

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

For a continuous and scalable synthesis of noble-metal-based nanocomposites, a novel photocatalytic reactor is developed and its structure, operation principles, and product quality optimization strategies are described.

A Continuous-flow Photocatalytic Reactor for the Precisely Controlled Deposition of Metallic Nanoparticles

A combination of solution and surface assisted synthesis opens new directions in the atomically precise synthesis of nanostructures. Scanning tunneling microscopy (STM) supplemented by non-contact atomic force microscopy (nc-AFM) enables detailed characterization of newly designed and generated carbon-based nano-objects.

Microscopic Visualization of Porous Nanographenes Synthesized through a Combination of Solution and On-Surface Chemistry

We report a one-pot hydrothermal synthesis of manganese ferrite clusters (MFCs) that offers independent control over material dimension and composition. Magnetic separation allows rapid purification while surface functionalization using sulfonated polymers ensures the materials are non-aggregating in biologically relevant medium. The resulting products are well positioned for biomedical applications.

Stable Aqueous Suspensions of Manganese Ferrite Clusters with Tunable Nanoscale Dimension and Composition

This article presents an optimized, experience-informed protocol for fabricating high-quality graphene-based moiré superlattice devices with precise twist angles, utilizing a modified dry transfer technique based on a highly tunable, custom-built transfer setup.

Optimized Fabrication Procedure for High-Quality Graphene-based Moir&#233; Superlattice Devices

The article presents the protocols of a cascade design oxidation process and a highly basic reduction reaction for innovative, scalable conversion of graphite into multilayer graphite oxide powder, graphene oxide nanosheets, supramolecular reduced graphene oxide hydrogel, and reduced graphene oxide nanomaterials.

Scalable Syntheses of Graphene Oxide and Reduced Graphene Oxide using Cascade Design Oxidation and Highly Basic Reduction Reactions

Learn to synthesize graphene nanofluids with controllable flake size distributions using exfoliation and centrifugation processes. This method enables precise control over size parameters for advanced materials applications.

Synthesis of Graphene Nanofluids with Controllable Flake Size Distributions

Explore More Videos