New low-cost technique converts bulk alloys to oxide nanowires

Production of nanowires from other materials is part of ongoing research that was not reported in the paper.

The dimensions of the nanowire structures can be controlled by varying the solvent and the processing conditions. The structures can be produced in diameters ranging from tens of nanometers up to microns.

"Minimization of the interfacial energy at the boundary of the chemical reaction front allows us to form small nuclei and then retain their diameter as the reaction proceeds, thus forming nanowires," Yushin explained. "By controlling the volume changes, surface energy, reactivity and solubility of the reaction products, along with the temperature and pressure, we can tune conditions to produce nanowires of the dimensions we want."

One of the attractive applications may be separator membranes for lithium-ion batteries, whose high power density has made them attractive for powering everything from consumer electronics to aircraft and motor vehicles. However, the polymer separation membranes used in these batteries cannot withstand the high temperatures generated by certain failure scenarios. As result, commercial batteries may induce fires and explosions, if not designed very carefully and it's extremely hard to avoid defects and errors consistently in tens of millions of devices.

Using low-cost paper-like membranes made of ceramic nanowires could help address those concerns because the structures are strong and thermally stable, while also being flexible - unlike many bulk ceramics. The material is also polar, meaning it would more thoroughly wetted by various battery electrolyte solutions.

"Overall, this is a better technology for batteries, but until now, ceramic nanowires have been too expensive to consider seriously," Yushin said. "In the future, we can improve mechanical properties further and scale up synthesis, making the low-cost ceramic separator technology very attractive to battery designers."

Fabrication of the nanowires begins with formation of alloys composed of one reactive and one non-reactive metal, such as lithium and aluminum (or magnesium and lithium). The alloy is then placed in a suitable solvent, which could include a range of alcohols, such as ethanol. The reactive metal (lithium) dissolves from the surface into the solvent, initially producing nuclei (nanoparticles) comprising aluminum.

Though bulk aluminum is not reactive with alcohol due to the formation of the passivation layer, the continuous dissolution of lithium prevents the passivation and allows gradual formation of aluminum alkoxide nanowires, which grow perpendicular to the surface of the particles starting from the nuclei until the particles are completely converted. The alkoxide nanowires can then be heated in open air to form aluminum oxide nanowires and may be formed into paper-like sheets.


The dissolved lithium can be recovered and reused. The dissolution process generates hydrogen gas, which could be captured and used to help fuel the heating step.

Though the process was studied first to make magnesium and aluminum oxide nanowires, Yushin believes it has a broad potential for making other materials. Future work will explore synthesis of new materials and their applications, and develop improved fundamental understanding of the process and predictive models to streamline experimental work.

The researchers have so far produced laboratory amounts of the nanowires, but Yushin believes that the process could be scaled up to produce industrial quantities. Though the ultimate cost will depend on many variables, he expects to see fabrication costs cut by several orders of magnitude over existing techniques.

"With this technique, you could potentially produce nanowires for a cost not much more than that of the raw materials," he said. Beyond battery membranes, the nanowires could be useful in energy harvesting, catalyst supports, sensors, flexible electronic devices, lightweight structural composites, building materials, electrical and thermal insulation and cutting tools.

The new technique was discovered accidentally while Yushin's students were attempting to create a new porous membrane material. Instead of the membrane they had hoped to fabricate, the process generated powders composed of elongated particles.

"Though the experiment didn't produce what we were looking for, I wanted to see if we could learn something from it anyway," said Yushin. Efforts to understand what had happened ultimately led to the new synthesis technique.

In addition to those already named, the research included Alexandre Magaskinski of Georgia Tech and Gene Berdichevsky of Sila Nanotechnologies.

>>101565
>The new technique was discovered accidentally
classic

>>102418
All the best discoveries are accidental anon

>>102454
>All the best discoveries are accidental anon
Especially when I accidentally humped my bed when I was a teen and accidentally came for the first time.

>>102519
Personally I was thinking of nylon, but that works too.

This kind of shit is lowkey infuriating.
Scientist fucking around leads to so much cool shit. Why don't we just load them up on addaral and LSD and lock them in a room with a simple task.

Three months we'd have those fuckers would be sending mice into the internet or getting ships pattialy fazed into walls.

I wonder how many buckets out there are filled with the answers.

>>102647
Not a terrible idea tbh

>>102418
>>102454

So much for the scientific method and making programs that plot out all the possible chemical reactions and all that crazy shit.

Or thinking that because we know science, that we know how physics actually works beyond just observing cause and effect.


>>102647

Its only pissing you off because its not happening as a result of people applying their intelligence.

Lets face it, we're not masters of the universe and there's a fuckton of shit left for us to find out... all that shit about living in space like its star trek is probably still possible even though
>duuuuhhhh laws of physics say otherwise

We dont know shit and things like this prove it.

>mfw we make a compound someday that people say is harder than Duke Nukem's dick and otherwise indestructible... made from some 5 alloy metal that was heated just right or in some funky combination of stages

> and people are like "that dont fucking make sense" but yet it still saws through tungsten carbide all day long without getting dull and they cant etch it with a laser

they're called discoveries for a reason


>>102519
Yes most disconcerting.

Funny thing was, I was trying to jack-o-lantern for almost a year and couldnt figure out how.

Then this asshole in my 6th grade class did a hurr-dee-durr hand shaking motion and later on I figured id try that.

boy that was a surprise, im just glad I had a dirty towel nearby from taking a shower before I went to bed

> mfw the leading edge in self pleasuring techniques at the time was discovered accidentally by observation, not even by trial and error