This work was supported by the National Research Foundation of Korea (NRF), grant no. 2014R1A4A1003712 (BRL Program), the Korea CCS R&amp;D Center (KCRC) grant funded by the Korea government (Ministry of Science, ICT &amp; Future Planning) (No. NRF-2014M1A8A1049303), an End-Run grant from KAIST funded by the Korea government in 2016 (Ministry of Science, ICT &amp; Future Planning) (N11160058), the Wearable Platform Materials Technology Center (WMC) (NR-2016R1A5A1009926), an National Research Foundation of Korea (NRF) Grant funded by the Korean Government (NRF-2017H1A2A1042006-Global Ph.D. Fellowship Program), a National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIP; Ministry of Science, ICT &amp; Future Planning) (NRF-2018R1C1B6002624), the Nano&#183;Material Technology Development Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Science, and an ICT and Future Planning (2009-0082580) and NRF grant funded by the Korea government (MSIP; Ministry of Science, ICT &amp; Future Planning) (NRF-2018R1C1B6002624).

1. Synthesis of SnO2 Nanotubes by Electrospinning and Subsequent Heat Treatment17
<ol>
	<li>Prepare an electrospinning solution.
	<ol>
		<li>Dissolve 0.25 g of tin chloride dihydrate in a solvent mixture of 1.25 g of ethanol and 1.25 g of dimethylformamide (DMF) at room temperature (RT, 25 &#176;C).</li>
		<li>After stirring for 2 h, add 0.35 g of polyvinylpyrrolidone (PVP) to the electrospinning solution and stir the mixture for another 6 h.</li>
	</ol>
	</li>
	<li>Perform an electro...

<ol>
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H., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Direct+realization+of+complete+conversion+and+agglomeration+dynamics+of+SnO2nanoparticles+in+liquid+electrolyte.">Direct realization of complete conversion and agglomeration dynamics of SnO2nanoparticles in liquid electrolyte.</a> ACS Omega. 2 (10), 6329-6336 (2017).</li><li>Cheong, J. Y., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+Situ+High-Resolution+Transmission+Electron+Microscopy+(TEM)+Observation+of+SnNanoparticles+on+SnO2+Nanotubes+Under+Lithiation.">In Situ High-Resolution Transmission Electron Microscopy (TEM) Observation of SnNanoparticles on SnO2 Nanotubes Under Lithiation.</a> Microscopy Microanalysis. 23 (6), 1107-1115 (2017).</li><li>Cheong, J. Y., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Revisiting+on+the+effect+and+role+of+TiO2+layer+thickness+on+SnO2+for+enhanced+electrochemical+performance+for+lithium-ion+batteries.">Revisiting on the effect and role of TiO2 layer thickness on SnO2 for enhanced electrochemical performance for lithium-ion batteries.</a> Electrochimica Acta. 258, 1140-1148 (2017).</li><li>Hwa, Y., Seo, H. K., Yuk, J. M., Cairns, E. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Freeze-Dried+Sulfur-Graphene+Oxide-Carbon+Nanotube+Nanocomposite+for+High+Sulfur-Loading+Lithium/Sulfur+Cells.">Freeze-Dried Sulfur-Graphene Oxide-Carbon Nanotube Nanocomposite for High Sulfur-Loading Lithium/Sulfur Cells.</a> Nano Letters. 17 (11), 7086-7094 (2017).</li><li>Yuk, J. M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=High-Resolution+EM+of+Colloidal+Nanocrystal+Growth+Using+Graphene+Liquid+Cells.">High-Resolution EM of Colloidal Nanocrystal Growth Using Graphene Liquid Cells.</a> Science. 336 (6084), 61-64 (2012).</li><li>Jeong, M., Yuk, J. M., Lee, J. Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Observation+of+Surface+Atoms+during+Platinum+Nanocrystal+Growth+by+Monomer+Attachment.">Observation of Surface Atoms during Platinum Nanocrystal Growth by Monomer Attachment.</a> Chemistry of Materials. 27 (9), 3200-3202 (2015).</li><li>Yuk, J. M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Real-Time+Observation+of+Water-Soluble+Mineral+Precipitation+in+Aqueous+Solution+by+In+situ+High-Resolution+Electron+Microscopy.">Real-Time Observation of Water-Soluble Mineral Precipitation in Aqueous Solution by In situ High-Resolution Electron Microscopy.</a> ACS Nano. 10 (1), 88-92 (2015).</li><li>Wang, C., Qiao, Q., Shokuhfar, T., Klie, R. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=High-Resolution+Electron+Microscopy+and+Spectroscopy+of+Ferritin+in+Biocompatible+Graphene+Liquid+Cells+and+Graphene+Sandwiches.">High-Resolution Electron Microscopy and Spectroscopy of Ferritin in Biocompatible Graphene Liquid Cells and Graphene Sandwiches.</a> Advanced Materials. 26 (21), 3410-3414 (2014).</li><li>Cheong, J. Y., Kim, C., Jang, J. S., Kim, I. -. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Rational+design+of+Sn-based+multicomponent+anodes+for+high+performance+lithium-ion+batteries:+SnO2@TiO2@reduced+graphene+oxide+nanotubes.">Rational design of Sn-based multicomponent anodes for high performance lithium-ion batteries: SnO2@TiO2@reduced graphene oxide nanotubes.</a> RSC Advances. 6 (4), 2920-2925 (2016).</li><li>Mel, A. -. A., Nakamura, R., Bittencout, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+Kirkendall+effect+and+nanoscience:+hollow+nanospheres+and+nanotubes.">The Kirkendall effect and nanoscience: hollow nanospheres and nanotubes.</a> Beilstein Journal of Nanotechnology. 6, 1348-1361 (2015).</li><li>Cheong, J. Y., Kim, C., Jung, J. -. W., Yoon, K. R., Kim, I. -. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Porous+SnO2-CuO+nanotubes+for+highly+reversible+lithium+storage.">Porous SnO2-CuO nanotubes for highly reversible lithium storage.</a> Journal of Power Sources. 373, 11-19 (2018).</li><li>Ao, X., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Porous+Honeycomb-inspired+design+of+ultrafine+SnO2@C+nanospheres+embedded+in+carbon+film+as+anode+materials+for+high+performance+lithium-+and+sodium-ion+battery.">Porous Honeycomb-inspired design of ultrafine SnO2@C nanospheres embedded in carbon film as anode materials for high performance lithium- and sodium-ion battery.</a> Journal of Power Sources. 359, 340-348 (2017).</li><li>Abellan, P., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Probing+the+Degradation+Mechanisms+in+Electrolyte+Solutions+for+Li-Ion+Batteries+by+in+Situ+Transmission+Electron+Microscopy.">Probing the Degradation Mechanisms in Electrolyte Solutions for Li-Ion Batteries by in Situ Transmission Electron Microscopy.</a> Nano Letters. 14, 1293-1299 (2014).</li></ol>

The authors have nothing to disclose.

There are critical steps within the protocol. First, the transfer of the graphene onto the TEM grid needs the researchers&#39; careful attention. It is important to handle the grids with tweezers and not damage any of grids, for instance by destroying the amorphous carbon membrane or bending the frame. These kinds of damages will result in a poor coverage of the graphene and affect the number of liquid pockets. In addition, placing the upper grid at the right position is critical. As described in the protocol, the top gr...

Recently, the consumption of energy has constantly increased, as well as the importance of high-performance energy storage devices. To meet such a demand, the development of lithium-ion batteries that have a high energy density, durability, and safety is necessary1,2. In order to develop batteries with superior properties, a fundamental understanding of energy storage mechanisms during battery operation is essential3,4,5.
In situ transmission electron microscopy (TEM) provides rich insights as it can show both structural and chemical information during the operation of batteries3. Among many in situ TEM techniques, GLCs have been used for the observation of the lithiation dynamics of nanomaterials6,7,8,9,10,11,12. GLCs consist of a liquid pocket sealed by two graphene membranes, which provide an actual electrode/electrolyte interface by preventing the evaporation of the liquid inside the high vacuum in a TEM column6,7. The advantages of GLCs are that they allow a superior spatial resolution and high imaging contrast because they employ electron transparent monatomic-thick graphene as liquid sealing membrane13,14,15,16. Also, conventional TEM can be applicable to observe the battery reactions, without using expensive in situ TEM holders.
In this text, we introduce how the lithiation reaction can be observed with GLCs. Specifically, electron beam irradiation produces solvated electrons inside the liquid electrolyte, and they initiate lithiation by separating Li ions from solvent molecules.
GLCs also serve as the most optimal platform to allow the direct observation of nanomaterials with various morphologies, including nanoparticles6,9, nanotubes7,10,11, and even multidimensional materials12. Together with the ex situ TEM analysis of electrode materials after the actual electrochemical cell testing, it is possible that the GLC system presented here can be used to investigate the fundamental reaction mechanism.
With such advantages of GLCs and ex situ experiments, we introduce here detailed experiment methods for researchers who are willing to carry out similar GLC experiments. The protocols cover 1) the synthesis of tin (IV) oxide (SnO2) nanotubes as the typical one-dimensional nanostructured electrode materials, 2) the electrochemical battery cell test, 3) the preparation of GLC, and 4) the performance of a real-time TEM observation.

<table border="0" cellpadding="0" cellspacing="0" style="width:1340px;" width="1340">
	<colgroup>
		<col />
		<col />
		<col />
		<col />
	</colgroup>
	<tbody>
		<tr height="24">
			<td height="24" style="height:24px;width:373px;">Tin chloride dihyrate</td>
			<td style="width:184px;">Sigma Aldrich</td>
			<td style="width:200px;">CAS 10025-69-1</td>
			<td style="width:583px;">In a glass bottle</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:373px;">Ethanol</td>
			<td style="width:184px;">Merck</td>
			<td style="width:200px;">CAS 64-17-5</td>
			<td>In a glass bottle</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:373px;">Dimethylformamide</td>
			<td style="width:184px;">Sigma Aldrich</td>
			<td style="width:200px;">CAS 68-12-2</td>
			<td>In a glass bottle</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:373px;">Polyvinylpyrrolidone</td>
			<td style="width:184px;">Sigma Aldrich</td>
			<td style="width:200px;">CAS 9003-39-8</td>
			<td>In a plastic bottle</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:373px;">Cell tester</td>
			<td style="width:184px;">KOREA THERMO-TECH</td>
			<td style="width:200px;">Maccor Series 4000</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:373px;">Cell tester 2</td>
			<td style="width:184px;">WonaTech</td>
			<td style="width:200px;">WBCS4000</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:373px;">Sodium perchlorate</td>
			<td style="width:184px;">Sigma Aldrich</td>
			<td style="width:200px;">CAS 7601-89-0</td>
			<td>In a glass bottle</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:373px;">25 gauge needle</td>
			<td style="width:184px;">Hwa-In Science Ltd.</td>
			<td style="width:200px;"></td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:373px;">1.3 M of lithium hexafluorophosphate (LiPF6) dissolved in EC/DEC with 10 wt% of FEC</td>
			<td style="width:184px;">PANAX ETEC</td>
			<td style="width:200px;"></td>
			<td>In a stainless steel bottle</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:373px;">Propylene carbonate</td>
			<td style="width:184px;">Sigma Aldrich</td>
			<td style="width:200px;">CAS 108-32-7</td>
			<td>In a glass bottle</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:373px;">Super P Carbon Black</td>
			<td style="width:184px;">Alfa-Aesar</td>
			<td style="width:200px;">CAS 1333-86-4</td>
			<td>In a glass bottle</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:373px;">Cell components (bottom cell, top cell, separator, gasket, spring, spacer)</td>
			<td style="width:184px;">Wellcos Corporation</td>
			<td style="width:200px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:373px;">Cell punch</td>
			<td style="width:184px;">Wellcos Corporation</td>
			<td style="width:200px;"></td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:373px;">Glove Box</td>
			<td style="width:184px;">Moisture Oxygen Technology (MOTEK)</td>
			<td style="width:200px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:373px;">Box Furnace</td>
			<td style="width:184px;">Naytech</td>
			<td style="width:200px;">Vulcan 3-550</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:373px;">Electrospinning device</td>
			<td style="width:184px;">NanoNC</td>
			<td style="width:200px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:373px;">Hydrofluoric acid</td>
			<td style="width:184px;">Junsei</td>
			<td style="width:200px;">84045-0350</td>
			<td>85%</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:373px;">Cu foil</td>
			<td style="width:184px;">Alfaaesar</td>
			<td style="width:200px;">38381</td>
			<td>Copper Thinfoil, 0.0125mm thick, 99.9%</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:373px;">Holy carbon Au grid</td>
			<td style="width:184px;">SPI</td>
			<td>Quantifoil R2/2 Micromachined Holey Carbon Grids, 300 Mesh Gold</td>
			<td>Quantifoil R2/2 Micromachined Holey Carbon Grids, 300 Mesh Gold</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:373px;">Isoprophyl alchol</td>
			<td style="width:184px;">Sigmaaldrich</td>
			<td style="width:200px;">W292907</td>
			<td>99.70%</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:373px;">Ammonium persulfate</td>
			<td style="width:184px;">Sigmaaldrich</td>
			<td style="width:200px;">248614</td>
			<td>98%</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:373px;">Transmission electron microscope (TEM)</td>
			<td style="width:184px;">JEOL</td>
			<td style="width:200px;">JEOL JEM 3010</td>
			<td>300 kV</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:373px;">Chemical vapor depistion (CVD)</td>
			<td style="width:184px;">Scientech</td>
			<td style="width:200px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:373px;">Charge coupled device (CCD)</td>
			<td style="width:184px;">Gatan</td>
			<td style="width:200px;">Orius SC200</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:373px;">Plasma Cleaner</td>
			<td style="width:184px;">Femtoscience</td>
			<td style="width:200px;">VITA</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:373px;">Electrospinning program</td>
			<td style="width:184px;">NanoNC</td>
			<td style="width:200px;">NanoNC eS- robot</td>
			<td></td>
		</tr>
	</tbody>
</table>

preparation of graphene liquid cells for the observation of lithium-ion battery material

In this work, we introduce the preparation of graphene liquid cells (GLCs), encapsulating both electrode materials and organic liquid electrolytes between two graphene sheets, and the facile synthesis of one-dimensional nanostructures using electrospinning. The GLC enables in situ transmission electron microscopy (TEM) for the lithiation dynamics of electrode materials. The in situ GLC-TEM using an electron beam for both imaging and lithiation can utilize not only realistic battery electrolytes, but also the high-resolution imaging of various morphological, phase, and interfacial transitions.

SnO2 nanotubes were fabricated by electrospinning and subsequent calcination, during which the nanotubular and porous structures could be seen clearly, according to the SEM image (Figure 3a). Such a nanotubular structure comes from the decomposition of PVP, while the Sn precursor in the core is moved outward due to the Kirkendall effect17,18. Additionally, Ostwald ripening ...

Watch this Scientific Journal Video about Preparation of Graphene Liquid Cells for the Observation of Lithium-ion Battery Material at JoVE.com

Preparation of Graphene Liquid Cells for the Observation of Lithium-ion Battery Material

Here, we present a protocol for the fabrication and preparation of a graphene liquid cell for in situ transmission electron microscopy observation, along with a synthesis of electrode materials and electrochemical battery cell tests.

In this work, we introduce the preparation of graphene liquid cells (GLCs), encapsulating both electrode materials and organic liquid electrolytes between ...

This graphene liquid cell enables transmission electron microscopy for these dynamics in a liquid electrolyte. Such dynamics can provide rich information of the working mechanisms of Lithium-ion batteries and contributes to designing advanced battery devices. The advantages of graphene liquid cell is that it allows TEM imaging in liquid electrolyte providing good spatial resolution and high imaging contrast.In addition to a superior quality of the image, it can also provide information of various morphological phase and interfacial transitions. With only a written protocol, it is difficult to follow this method because many technical steps are conducted by hand. A lot of the skills require accuracy and precision, where the use of patience is highly recommended.Even though you follow every protocol correctly, you can still fail the experiment because handling graphene and the graphene transfer grids is difficult. To begin, prepare the electrospinning solution as described in the accompanying text protocol. Transfer it into a ten milliliter syringe and equip the syringe with a 25 gauge needle.Then wash the target. Take a rectangular piece of flexible stainless steel and wash it with deionized water, followed by ethanol. Repeat this process two to five times.Once clean, air dry the steel at 60 degrees Celsius for 10 minutes. Once dry, fix the flexible stainless steel onto the drummer with tape. Next, open the electrospinning controller software and enter a flow rate of 10 microliters per minute, requiring a total solution volume of five milliliters.Fix the syringe with the 25 gauge needle into the electrospinning device and use tape to fix it in place. Now press the syringe towards the collector until the electrospinning solution flows well through the 25 gauge needle. Then connect the tip of the needle to the double-ended crocodile clips which are also connected to the collector.Before initiating the electrospinning program, turn on the roller and spin the collector at 100 rpm. Then initiate the electrospinning program software. When the spinning begins, modulate the applied voltage to 16 kilovolts so that the Taylor cone forms.When the electrospinning process is finished, scrap the as-spun nanofibers on the flexible stainless steel with a razor and transfer them into an alumina box. Then insert the alumina box into the box furnace and set the heat treatment conditions for the box furnace. After calcination, cool down the furnace to 50 degrees Celsius and then transfer the calcined nanotubes to a glass vial.To begin, prepare the electrode slurry. Place it on the top side of the copper foil on the glass substrate and cast it evenly to a thickness of around 60 microns using a casting roller. Then air dry the slurry cast foil at 60 degrees Celsius for 10 minutes.Once dry, seal it inside a plastic bag until ready for cell assembly. To begin cell assembly, heat a convection oven to 150 degrees Celsius and place the slurry cast copper foil into the oven. Pull the vacuum in the oven using a rotary pump to dry the residual solvent in the slurry while avoiding oxidation of the copper foil.After heating the slurry cast copper foil at 150 degrees Celsius for two hours, refill the convection oven with air by closing the vacuum line and opening the vent line in the rotary pump to open the chamber. Then take the slurry cast copper foil out of the chamber and punch it with a circle puncher. Weigh the punched slurry cast copper foil.Use half a cell for the assembly of the battery cells and place the slurry cast copper foil into the bottom of the battery cell. Then transfer the samples to the ante-chamber of the glove box. Vacuum the ante-chamber for 30 minutes and then transfer the samples to the inside glove box.In the glove box, assemble the battery cells, starting with the bottom battery cell, then the slurry cast copper foil, the separator, the gasket, the spacer, the spring, and finally, the top battery cell. Use a compactor to compress the battery cell into a complete battery cell. Then move the battery cells into the ante-chamber of the glove box.Once the vacuum has been released, remove the battery cells from the glove box. Age the battery at room temperature for one to two days. Then insert the cells in the battery cell tester.Calculate the appropriate current and then apply the proper current for each battery cell using the battery cell tester program. To begin, synthesize graphene by chemical vapor deposition and use a pair of scissors to cut the copper foil with the graphene to three by three millimeter squares. Place four copper foil pieces between two glass slides and press to make them flat.Next place fully carbon gold grids on each piece of copper foil. Drop 20 microliters of isopropyl alcohol on the gold grid copper foil combo. Then remove the alcohol and dry the sample at 50 degrees Celsius for five minutes.Next clean a six centimeter glass Petri dish with isopropyl alcohol and deionized water to avoid contamination with silicon particles. Then add ten milliliters of 0.1 molar ammonium persulfate to the dish and etch the copper foil. Incubate the sample in the solution for six hours.Use a platinum loop to move the gold grids to a glass Petri dish filled with deionized water and heat it to 50 degrees Celsius in order to fully remove any remaining contaminants from the etched. Then remove the grids and dry them for six hours at room temperature. Prepare the electrolyte and nanotube mixture by dispersing 0.06 grams of the nanotube powder in 10 milliliters of electrolyte, which is composed of 1.3 molar lithium hexafluorophospate and ethylene carbonate and diethylene carbonate in a three to seven volume ratio with 10 weight percent of fluoroethylene carbonate.Then move the graphene transferred grids and the electrolyte mixture into a glove box that is filled with argon. To assemble the cell, first place one grid on the bottom. Then drop 20 microliters of the electrolyte mixture on the bottom grid.Quickly use a pair of tweezers to place another grid on top of the bottom grid before the electrolyte dries. Dry the sample inside the glove box for 30 minutes, during which the liquid is spontaneously encapsulated between the two graphene sheets as it dries. The tin iv oxide nanotubes fabricated by electrospinning and subsequent calcination are shown here in an SEM image.TEM shows that such porous sites are more visually clear, indicated by a number of white spots within the nanotubes. This is because the crystal structures of tin iv oxide are polycrystalline cassiterite structures. In terms of electrochemical characteristics of the tin iv oxide nanotubes, the charge and discharge profile exhibits stable voltage profiles with an initial coulombic efficiency of 67.8%The voltage plateau, which exists at 0.9 volts, can be attributed to the two phase reaction.The tin iv oxide nanotubes exhibit stable cycling at 500 milliamps per gram with coulombic efficiencies above 98%In addition, the nanotubes retain considerable capacity, even at a high current density of 1, 000 milliamps per gram. A time series TEM video of graphene liquid cells shows at the multiple liquid pockets whose sizes range from 300-400 nanometers. Through constant electron beam irradiation, dissolved electrons and radicals trigger a secondary reaction with a salt and solvent.Here the decomposition of electrolyte and the formation of a SEI layer were observed at the initial stage. Take extra care when handling graphene and TEM grid. If you don't handle graphene and grid properly, they can be easily damaged.In the cell assembly, it is important to compress the cell tightly so that the electrolyte does not come out of the cells. This procedure can also be utilized in observing dynamics of sodium-ion batteries, magnesium-ion batteries, and secondary-ion batteries.

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Research

JoVE Journal

Engineering

8.9K ビュー.  Korea Advanced Institute of Science and Technology. このグラフェン液体セルは、液体電解質中のこれらのダイナミクスの透過電子顕微鏡検査を可能にする。このようなダイナミクスは、リチウムイオン電池の動作機構の豊富な情報を提供し、高度なバッテリデバイスの設計に貢献することができます。グラフェン液電池の利点は、液体電解質中のTEMイメージングが良好な空間分解能および高いイメージングコントラスト?...