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Gold Nanoparticles Turn Trees Into Streetlights
An anonymous reader writes "Street lights are an important part of our urban infrastructure — they light our way home and make the roads safe at night. But what if we could create natural street lights that don't need electricity to power them? A group of scientists in Taiwan recently discovered that placing gold nanoparticles within the leaves of trees causes them to give off a luminous reddish glow. The idea of using trees to replace street lights is an ingenious one — not only would it save on electricity costs and cut CO2 emissions, but it could also greatly reduce light pollution in major cities."
I welcome our reddish glowing leafy overlords.
The world's burning. Moped Jesus spotted on I50. Details at 11.
Make it occur naturally.
Or rather - aren't there some kinds of mushrooms and other flora that glow in the dark? Why not just splice that plant with a tree. I know, I use the term splice like its an easy task.
Yeah because mining gold and refining it and the turning it into nano-particles takes zero energy....
There are 4 boxes to use in the defense of liberty: soap, ballot, jury, ammo. Use in that order. Starting now.
I'd be chopping down trees everywhere!!!!
Nah, I know the particles are so small it would make the effort a waste of time. That aside, on a serious note, what happens to the "streetlights" when the Fall comes each year?
StarTrekPhase2 - The Five Year Mission Continues!
The nice thing about street lights, though, is that they don't fall off every autumn.
A group of scientists in Taiwan recently discovered that placing gold nanoparticles within the leaves of trees, causes them to give off a luminous reddish glow.
Even better, a group of US capitalists has discovered that setting fire to the trees produces an even more luminous glow, at no cost to the company, keeping the gold available for executive bonuses.
To summarise the summary of the summary: people are a problem. ~ h2g2
When I was a kid, sprinkling heavy metals around was considered a bad thing.
My, how times change.
-Peter
I can see at least one problem with this idea...
Necron69
So it appears as though the effect requires an outside energy source to be useful. Nothing to see here, move on.
Dog is my co-pilot.
I am speaking strictly out of self-interest here when I say this would be incredibly awesome.
As someone who's family has been in the tree business for a few generations, I would love our products to have a new utility that people actually see as practical. Currently, not many consumers understand that trees are not just for aesthetics, but can provide many practical benefits. Make 'em light up and people (municipalities, really) will be all over 'em.
Someone flopped a steamer in the gene pool.
The article says:
...A lot of light emitting diode, especially white light emitting diode, uses phosphor powder to stimulate light of different wavelengths. However, phosphor powder is highly toxic and its price is expensive. As a result, Dr. Yen-Hsun Wu had the idea to discover a method that is less toxic to replace phosphor powder. ...
By implanting the gold nanoparticles into the leaves of the Bacopa caroliniana plants, the scientists were able to induce the chlorophyll in the leaves to produce a red emission. Under a high wavelength of ultraviolet light, the gold nanoparticles were able to produce a blue-violet fluorescence to trigger a red emission in the surrounding chlorophyll.
So it sounds like the trees need a "high wavelength of ultraviolet light" to get them to glow. Seems like they are just replacing the phosphor that makes a white LED glow with these gold implanted leaves. But you'd still need a UV light source (which could be an array of UV LED's?).
I'm not sure that this is really an environmental win -- replacing an array of white LED's that last 10 years with an array of UV LED's that point to trees that need their leaves to be impregnated with gold (and replaced annually?) doesn't sound all that environmentally friendly. How bad is the LED phosphor for the environment?
Once again, proof that journalists should just stick to describing the research rather than coming up with groundbreaking applications which, as you'd almost certainly expect, don't work. The nanoparticles don't make the leaves glow "naturally", you have to shine UV light on them. Then they fluoresce red. But if you want to light streets using this technology, can I recommend just coating the UV light with leaves and doing away with the tree (we don't want to waste UV light after all)? In fact, ignore the leaves - just use a fluorophore. Actually, better yet, why not use a fluorophore that doesn't emit red light? How about something more akin to natural light, like yellow? And make it sensitive to blue light rather than UV (because generating UV is harder). And finally, while we're at it, make the light source solid-state.
Congratulations, you've just invented the white LED.
Valar call prior art!
Ezekiel 23:20
"...not only would it save on electricity costs and cut CO2 emissions, but it could also greatly reduce light pollution in major cities."
What a stupid thing to say. If they provide enough light to replace street lights, then they contribute just as much to light pollution as the street lights do.
Unless and until we switch over to electric cars en masse, street lights are NOT wasting electricity.
One of the two primary purposes of street lights is to consume the power generated by base-load powerplants that mu$t spin 24/7. Without our vast numbers of street lights, night-time voltages would rise above 130 and start frying your appliances.
Ever wondered why the electric company does not charge money, if you ask them to add a street light to the pole near your house? That's the reason.
FATMOUSE + YOU = FATMOUSE