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1Step 1
Step 1. Functionalization and Dispersion of iMWCNT
So you have recieved some cheap 90% clean multi walled carbon nanotubes. That's great but they are pretty useless as is, the first order of business is to clean and functionalize them using nitric acid , 30% hydrogen peroxide and an ultrasonic cleaner.
Cover your work area with disposable materials that you can throw away, don long gloves, safety glasses, lab coat, covered toe boots and a respirator before cracking the container that contains the nanotubes. The respirator should be able to filter organics and fine particulates. It would be best to do this in a filtered fume hood but it is not necessary if you are careful and don't create alot of dust.
Add an amount usually 20 grams is what I use, to the tared mason jar.
Nitric acid is pretty benign but H2O2 can start fires very easily. Have a fire extinguisher on hand.
Add either conc. nitric acid and 30% H2O2 in a 50/50 by volume ratio or soley 30% H2O2 to the jar just covering the nanotubes. The nitrogen functionalized tubes will be used in the Cathode and the purely oxidized iMWCNT will be used in the primary and secondary Anode. Place the stick blender in the Jar and place the jar into the ultrasonic bath. Start the bath and begin blending on high, blend for 30 seconds every 5 minutes and sonicate for 60 minutes total.
The nitric acid will fume and you definitely don't want to breathe it so wear the respirator that filters organics. DONT DO THIS IN YOUR HOUSE. The H202 will also release oxygen gas so have no flames present.
After 60 minutes of continuous sonication and blending you are ready to filter the iMWCNT. Attach a Buchner funnel to a filter flask and place a whatmann number 1 filter paper in the Buchner. Attach the vacuum line to your filter flask and turn the pump on. Wet the filter paper down so it forms a seal with the buchner and is pushed down by atmosphere.
See my how to filter video here. I had trouble removing excess nitric from these iMWCNT so I ball milled them with distilled water overnight, other than that the procedure is the same your vessel will be the reaction vessel instead of the ball mill.
Slowly pour the foamy functionalized iMWCNT into the funnel and rinse with distilled water untill the PH of the effluent is nuetral. It will often take about a full gallon to rinse 20g of fiMWCNT.
Allow the vacuum to be continually pulled once f-iMWCNT have been rinsed, this will assist in drying the filter cake.
Dump the filter cake after drying for a few minutes onto a tared aluminum raft, scrape down the sides of the Buchner funnel to remove as much of the solid as possible.
Place the aluminum raft into a drying oven and dry overnight at 175 degrees Celsius and 25 inches of vacuum. When drying is complete weigh the raft with f-iMWCNT to determine losses due to amorphous carbon and iron being removed from the as bought i-MWCNT. When using only 30% H2O2 to functionalize there will be less losses due to the iron and amorphous carbon still present.
Record all weights in your lab notebook.
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2Step 2
Step 2. Functionalization and Dispersion of Graphite to make Graphene Oxide
Follow all lab safety procedure.
Follow the above procedure substituting 75 mesh ultra fine graphite for the iMWCNT.
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3Step 3
Step 3. Cleaning and Dispersion of Chinese Supercritically Extracted Asphaltenes
Follow all lab safety procedure.
Place 20 grams of dried asphaltenes into a tared flask, record the weight. Add 300-400 mL of acetone to the jar.
Place a stick blender into the jar and place the jar into the ultrasonic bath, blend and sonicate as above for 30 minutes. The mixture will get very warm, be sure not to have any ignition sources nearby as warm acetone is very flammable, always have a oil rated fire extinguisher within reach.
Following the above procedure in step 1 filter the asphaltenes and wash with acetone.
Place the wet asphaltenes onto a tared aluminum raft and place into your vacuum oven. Dry at 80 degrees Celsius and 25 inches of mercury for 1 hour.
Record the weight of the washed asphaltenes and raft. Calculate losses and record in your lab notebook.
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4Step 4
Step 4. Oxidation and functionalization of iMWCNT and Graphite using Potassium Permanganate to make ox iMWCNT and Graphene Oxide containing MnO2 groups. These will be used in conjunction with amorphous Silica in the Anode.
Following all lab safety procedures as well as wearing clothes you do not mind permanent brown stains on do the following.
Place 20 grams of iMWCNT or 75 mesh Graphite into a tared reaction vessel. Record the weight.
In a second vessel add 4 grams of Potassium Permanganate record the weight and then add 250 mL of distilled water. Observe the most beautiful purple imaginable. Thoroughly mix the water and pot perm until all solids are dissolved this may require heating.
Add the pot perm solution to the reaction vessel and blend for 2 minutes with a stick blender.
Place the reaction vessel into the ultrasonic bath and set the timer for 2 hours. Every thirty minutes blend with the stick blender for a period of 2 minutes.
When the 2 hours is over prepare your filtering set up as done in the above steps.
Filter the suspension, it will take some time but as the liquid begins to recede you will need to add distilled water to rinse any excess potassium permanganate solution out of the filter cake. Keep adding distilled water until the filtrate runs clear.
You may need to place the iMWCNT back into a reaction vessel and blend with distilled water in order to remove all the excess pot perm solution. I have found that the graphene oxide is much less absorbent and can generally be rinsed clean.
Place the cake on a tared aluminum foil boat and dry overnight in a vacuum oven at 175 degrees C and 25 inches of vacuum.
Record the dry weight and calculate losses.
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5Step 5
Step 5 Ball milling to break up clumps of dried nano carbons.
Ball mill all of the prepared nano carbons, they will naturally agglomerate when dried to completion as all the water molecules are pulled from the inter-facial regions.
Ball milling will break up the clumps and make processing into cathode and anode easier.
I usually ball mill overnight using alumina ceramic ball bearings recycled from jet turbine engines and then check on the state of things, if residual moisture is present they will still clump together and obviously need to by dried further.
If everything is dried and ball milled for 12 hours a very fine dust will be created, let the ball mill sit for a few hours and gather a tared aluminum foil flat, as well as a colander.
Nanotube coated alumina very conductive.
Shake the colander to get the dust to fall through and retain the alumina balls. You will want to wear a respirator suitable to filter fine dusts as it is almost like smoke rising when a sufficiently fine powder is milled.
Record the weight of the recovered powder and calculate losses.
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6Step 6
Step 6
Take a break from that chemistry labor of love and start your artificial muscle build. Follow this video for a breakdown, you will have to pause on the text to read it, as I am still honing my editing skills.
Here is part 1 in a maybe 3 part series.
I started over on the steam powered muscle, not sure if that is going to work out up there, in the mean time I am diversifying my assets.
I started a sole ferrofluid muscle using string trimmer line. Alot of this has to be place holder until I get set on materials and build instructions in the mean time here are some pictures of the new steam and new ferro.
Combine Smooth-Ons Ecoflex 00-50 or Dragon skin medium set with 1.5% by weight pristine iMWCNT, and 1.5% by weight oxidized iMWCNT. Stir with a drill to insure thorough mixing, Using the mold provided and printed attach the top to vacuum and the bottom to two lines going to the silicone mixture. Vacuum until you see black start to appear in the bleeder cloth. Then immediately disconnect the vacuum and let the silicone cure.
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7Step 7
Sorry tables don't work on here.
Regardless combine by weight.
Diatomaceous Earth 20%
Lithium Hydroxide 30%
Graphene Oxide 40%
OxiMWCNT 10%
And calcine in a crucible containing charcoal with a propane forge for 30 minutes. Just get it hot, ideal temperature is around 700 degress F. This will reduce the silicon dioxide into silicon carbide and reduce the nano carbons increasing conductivity while covalently bonding them together around the DE.
In a mason jar or suitable vessel combine:
Elemental Sulfur 30%
N-Graphene Oxide 20%
N Ox iMWCNT 20%
Asphaltenes 10%
Natural Zeolite Clinoptilolite 10%
Urea 10%
Microwave on high for 1 minute 30 seconds. Stir, then microwave at 10 second intervals making sure to prevent boiling over. Microwave for 5 minutes total. This will reduce the carbon so it will more readily retain the sulfur.
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8Step 8
Step 8
Cleaning nickel foil and copper foil for better performance and a higher surface area.
Using dilute nitric acid or muriatic acid clean the foils so the binder can more readily adhere. If the foil is very oily it may be beneficial to clean with alconox then rinse with distilled water.
I also sand my foils to increase surface area, I am not sure if it matters yet.
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9Step 9
Step 9 better reduction of materials/annealing = higher conductivity and actual silicon carbide. The microwave technique just wasn't cutting it.
Build a propane forge, I used a 50/50 mix of plaster of paris and play sand. Use youtube to look for more builds, this is a low quality low temperature forge but we only need about 700 degrees F so it will be perfect.
You need to build a steel crucible as well with a vent hole.
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10Step 10
Use the above cathode and anode materials, mixed with a 10% by weight chitosan and dispersed in a 50/50 mixture of household vinegar and acetone. Disperse at a ratio of 1g to 50mL. Ultra-sonicate and stick blend for a period of two minutes.
Weigh the foils before hand to determine when you have a balanced amount of material on each. Silicon can intercalate twice the number of lithium atoms that Sulfur can, I'll let you do the math for now I will update later with a picture when I get around to drawing it.
Spray the cathode electrode onto the nickel foil and the anode material onto the copper foil.
For the cathode we will need to also mix up the porous graphene oxide seperator in order to retain poly sulfides. This will allow the battery to last more cycles.
Combine
50% graphene oxide
30% ox iMWCNT
10% Natural Zeolite Clinoptilolite
10% Chitosan
Disperse in the same liquid as mentioned above and airbrush onto the cathode to completely cover the electrode.
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