Thawj thawj zaug, cov kws tshawb fawb tau tsim lub teeb -emitting diodes (LEDs) ntawm lub teeb yuag hloov tau yooj yim hlau ntawv.
Cov kws tshaj lij ntawm Ohio State University tab tom tsim cov ntawv ci raws li LEDs rau lub teeb ci ultraviolet (UV) uas cov tub rog thiab lwm tus tuaj yeem siv los ntxuav cov dej haus thiab ua kom tsis muaj menyuam cov khoom siv kho mob.
In the journal Applied Physics Letters, the researchers describe how they designed the LEDs to shine in the high-energy "deep" end of the UV spectrum. The university will license the technology to industry for further development.
Lub teeb sib sib zog nqus UV twb tau siv los ntawm cov tub rog, cov koom haum pab tib neeg thiab kev lag luam rau kev siv xws li kev tshawb nrhiav cov tshuaj lom neeg mus rau kev kho cov yas, piav qhia Roberto Myers, tus kws tshaj lij ntawm cov ntaub ntawv tshawb fawb thiab engineering ntawm Ohio State.
Qhov teeb meem yog qhov sib sib zog nqus sib sib zog nqus- UV teeb hnyav dhau los yooj yim nqa mus.
"Right now, if you want to make deep ultraviolet light, you've got to use mercury lamps," said Myers, who is also an associate professor of electrical and computer engineering. "Mercury is toxic and the lamps are bulky and electrically inefficient. LEDs, on the other hand, are really efficient, so if we could make UV LEDs that are safe and portable and cheap, we could make safe drinking water wherever we need it."
He noted that other research groups have fabricated deep-UV LEDs at the laboratory scale, but only by using extremely pure, rigid single-crystal semiconductors as substrates—a strategy that imposes an enormous cost barrier for industry.
Cov ntawv ci-raws li nanotechnology tuaj yeem ua kom loj- nplai ntau lawm ntawm lub teeb, pheej yig dua thiab ntau tus phooj ywg ib puag ncig sib sib zog nqus-UV LED. Tab sis Myers thiab cov kws tshawb fawb cov kws kho mob cov tub ntxhais kawm Brelon J. Tej zaum vam tias lawv cov thev naus laus zis yuav ua qee yam ntxiv: tig ib qho kev tshawb fawb niche hu ua nanophotonics rau hauv kev lag luam siv tau.
"People always said that nanophotonics will never be commercially important, because you can't scale them up. Well, now we can. We can make a sheet of them if we want," Myers said. "That means we can consider nanophotonics for large-scale manufacturing."
Ib feem, qhov kev txhim kho tshiab no tso siab rau qhov zoo- tsim cov txheej txheem kev loj hlob semiconductor hu ua molecular beam epitaxy, uas cov ntaub ntawv vaporized elemental nyob rau saum npoo thiab tus kheej- teeb tsa rau hauv cov txheej txheem lossis nanostructures. Cov kws tshawb fawb hauv Ohio State tau siv cov txheej txheem no los cog cov ntaub pua plag ntawm cov ntaub pua plag ntawm cov ntaub nplaum uas ntim cov txhuas gallium nitride ntawm cov ntawv hlau xws li titanium thiab tantalum.
The individual wires measure about 200 nanometers tall and about 20-50 nanometers in diameter—thousands of times narrower than a human hair and invisible to the naked eye.
Hauv kev sim kuaj, cov nanowires loj hlob ntawm cov ntawv hlau ci ci ze li qhov ci ntsa iab zoo li cov khoom tsim los ntawm cov khoom kim dua thiab tsis yooj yim dua ib zaug - siv lead ua silicon.
Cov kws tshawb fawb tab tom ua haujlwm los ua kom cov nanowire LEDs txawm ci dua, thiab tom ntej no yuav sim ua kom cov xaim ntawm cov ntawv ci ua los ntawm cov hlau ntau dua, suav nrog hlau thiab txhuas.
