Thaum Lub Kaum Ob Hlis 23, ib pab pawg tshawb fawb los ntawm Lub Tsev Haujlwm Saib Xyuas Cov Khoom Siv Tshiab ntawm Pohang University of Technology tau tshaj tawm tias lawv tau tsim ib hom tshiab ntawm LED lub teeb uas tawm lub teeb sib sib zog nqus ultraviolet raws li cov txheej txheem sandwich ntawm graphene txheej thiab hexagonal boron nitride (hBN) txheej. . Pab neeg tshawb fawb tau piav qhia tias txog tam sim no, cov khoom siv uas tso tawm cov duab sib sib zog nqus ultraviolet feem ntau yog siv cov khoom ua los ntawm mercury lossis aluminium gallium nitride, tab sis cov khoom siv ib txwm muaj teeb meem nrog kev ua qias tuaj lossis luminous efficiency. Cov txiaj ntsig kev tshawb fawb tsis ntev los no tau tshaj tawm hauv ntiaj teb-ntaub ntawv xov xwm kev kawm nto moo Nature Communications.
▲ h-BN deep ultraviolet LED. Schematic showing strong deep ultraviolet emission using graphene, h-BN, and van der Waals heteronanomaterials with graphene structures (C)
Raws li Pohang University of Technology, cov khoom tseem ceeb tam sim no siv hauv kev tshawb fawb tob ultraviolet LED yog aluminium gallium nitride (tom qab no hu ua AlxGa1-xN). Txawm li cas los xij, cov khoom siv no muaj qhov kev txwv tseem ceeb uas nws cov khoom luminescent deteriorate sai sai thaum lub wavelength tau luv.
In order to break through this limitation, POSTECH uses h-BN as a device material, whose single-atom layer structure is similar to graphene and its appearance is transparent, so it is also called "white graphene".
Nws tau tshaj tawm tias, tsis zoo li AlxGa1-xN, nws tawm lub teeb ci ntsa iab hauv thaj av ultraviolet tob thiab suav tias yog cov khoom siv tshiab uas tuaj yeem siv los tsim cov LED sib sib zog nqus ultraviolet. Txawm li cas los xij, vim qhov sib txawv ntawm qhov loj, nws nyuaj rau txhaj tshuaj electrons thiab qhov, yog li LEDs tsis tuaj yeem ua. Tab sis yog tias qhov hluav taws xob muaj zog siv rau h-BN nanofilm, cov hluav taws xob thiab qhov tuaj yeem raug txhaj los ntawm qhov cuam tshuam. Yog li ntawd, cov khoom siv LED raws li kev sib tw ntawm van der Waals heterogeneous nanomaterials nrog graphene, h-BN, thiab graphene tau tsim, thiab nws tau lees paub los ntawm kev sib sib zog nqus UV spectroscopy tias cov khoom siv tiag tiag tawm lub teeb muaj zog UV.
Professor Jin Zhonghuan from the Department of Materials Science and Engineering of the university said: "The development of new high-efficiency LED materials in a new wavelength range can be a starting point for the application of optical devices. The significance of this research on h-BN lies in the realization of deep ultraviolet LED manufacturing. .
In addition, compared with the existing AlxGa1-xN material, it has significantly higher luminous efficiency, and the device can be miniaturized. "
