Hemp Fibers Make Better Supercapacitors Than Graphene 178
biodata (1981610) writes "BBC News is reporting findings published in the journal ACS Nano by Dr David Mitlin from Clarkson University. Dr. Mitlin's team took waste hemp stems and recycled the material into supercapacitors with performance as good, or better, than those built from graphene, at a fraction of the raw materials cost. "We're making graphene-like materials for a thousandth of the price - and we're doing it with waste. The hemp we use is perfectly legal to grow. It has no THC in it at all - so there's no overlap with any recreational activities," Mitlin says.
Marijuana... (Score:5, Interesting)
Marijuana. Is there anything it CAN'T do?
Re:suitable for home use? (Score:5, Interesting)
I'd love these for a solar array where energy stored for unit volume is important, but not critical (like it is in a car or RV) for a number of reasons:
1: Hemp is a lot less nasty for the environment than graphene.
2: This could be used as a buffer for the chemical batteries, since you don't have to worry about limiting amps coming in. Come "shoulder hours", the supercaps can be charging the batteries at exactly the amperage rate they need even after the sun is down, greatly improving the system's efficiency.
3: The lifespan of a capacitor is a lot longer than a battery because electricity is stored physically, not chemically. So, if space is less of an issue, large supercaps can be used without worrying about replacement every 5-10 years (or 2-3 years with Li-ion) batteries.
So, for an off-grid circuit (one that never goes near mains power and pretty much acts as a UPS), having this technology would go far.
Re:Legal... sort of (Score:2, Interesting)
No. There is no replacement yet for hemp cloth that is as good or better in hot weather. Flax comes close but isn't as durable. The ridiculous state of the law makes flax cheaper than hemp which would otherwise outperform it in all aspects including price. Synthetic fibers are trash for clothing if you have to do anything beyond sitting in an air-condition room.
Re:/Oblg. Hemp for Victory ! (Score:5, Interesting)
Re:suitable for home use? (Score:4, Interesting)
Asbestos is just silicate rock. Structure makes a difference. [gizmag.com].
Graphene is just a sheet of carbon, but it's structure gives it novel properties - it wouldn't be a super-material if it didn't, just because it's all cool and awesome doesn't mean it's also inert and harmless.