1. Basic Chemistry ndi Crystallographic Design ya Taxi SIX
1.1 Boron-Rich Framework ndi Electronic Band Framework
(Calcium Hexaboride)
Calcium hexaboride (TAXI ₆) ndi stoichiometric metal boride yochokera kumayendedwe achilendo-earth ndi alkaline-earth hexaborides., amasiyanitsidwa ndi kusakaniza kwake kwamtundu umodzi wa ionic, covalent, ndi zitsulo kugwirizana makhalidwe.
Mapangidwe ake a kristalo amatengera latisi yamtundu wa CsCl (danga gulu Pm-3m), komwe maatomu a kashiamu amakhala m'mphepete mwa cube ndi mawonekedwe owoneka bwino atatu a boron octahedra (B ₆ zipangizo) amakhala pa body body.
Boron octahedron iliyonse imapangidwa ndi ma atomu asanu ndi limodzi a boron omwe amamatira molumikizana bwino kwambiri., kupanga chinsinsi, Netiweki yopanda ma elekitironi yothandizidwa ndi kusamutsa mtengo kuchokera ku atomu ya electropositive calcium.
Kusintha mtengo uku kumabweretsa bandi yodzaza pang'ono, kupatsa taxi sikisi yokhala ndi magetsi okwera modabwitsa pazinthu za ceramic– pa dongosolo la 10 ⁵ S/m pa kutentha kwa chipinda– ngakhale pali kusiyana kwakukulu kwa pafupifupi 1.0– 1.3 eV monga idakhazikitsidwa ndi kafukufuku wa optical absorption ndi photoemission.
Chiyambi cha chinsinsi ichi– high conductivity yomwe ilipo mbali ndi mbali yokhala ndi bandgap yayikulu– yakhala nkhani yophunzira kwambiri, ndi malingaliro owonetsa kuwonekera kwa zolakwika zamkati, pamwamba conductivity, kapena njira zoyendetsera polaronic kuphatikiza kuphatikiza ma electron-phonon.
Kuwerengera kwaposachedwa kwa zikhulupiriro zoyambira kumachirikiza kapangidwe kamene kagawo kakang'ono ka ma transmission kumapeza makamaka kuchokera ku Ca 5d orbitals., pomwe gulu la valence limayang'aniridwa ndi mayiko a B 2p, kupanga slim, dispersive gulu lomwe limalimbikitsa kuyenda kwa ma elekitironi.
1.2 Chitetezo cha Thermal ndi Mechanical mu Nkhani Zazambiri
Monga ceramic refractory, TAXICAB ₆ ikuwonetsa kukhazikika kwamafuta modabwitsa, ndi malo osungunuka kwambiri 2200 ° C ndi kuchepa kwapang'onopang'ono kwapang'onopang'ono m'makonzedwe a inert kapena vacuum cleaner mpaka 1800 °C.
Kutentha kwake kwakukulu komanso kuchepetsedwa kwa nthunzi kumapangitsa kukhala koyenera kumangidwe kwapamwamba komanso kothandiza komwe kukhulupirika kwazinthu pansi pa nkhawa yamafuta ndikofunikira..
Mwamakani, CaB ₆ ili ndi kulimba kwa Vickers pafupifupi 25– 30 GPA, kuyiyika pakati pa zovuta zodziwika bwino ndikuwonetsa mphamvu za B– B covalent bond mkati mwa octahedral framework.
Nkhaniyi ikuwonetsanso kutsika kwa coefficient ya kuwonjezereka kwa kutentha (~ 6.5 × 10 ⁻⁶/ K), zimathandizira kuti pakhale kutentha kwamphamvu kwambiri– Chofunika kwambiri pazigawo zozikidwa pa kutentha kwachangu ndi kuzizira.
Nyumba zogona izi, kuphatikizidwa ndi kusakhazikika kwamankhwala kuzitsulo zosungunuka ndi slags, kulimbikitsa kugwiritsidwa ntchito kwake mu crucibles, masamba a thermocouple, ndi mayunitsi ozindikira kutentha kwambiri m'malo opangira zitsulo ndi mafakitale.
( Calcium Hexaboride)
Komanso, TAXICAB ₆ imasonyeza kukana kwapadera kwa okosijeni zomwe zalembedwa pansipa 1000 °C; komabe, pamwamba pa malire awa, Kuchuluka kwa okosijeni ku calcium borate ndi boric oxide kumatha kuchitika, kumafuna zomaliza zodzitchinjiriza kapena kuwongolera magwiridwe antchito mumalo obwera ndi okosijeni.
2. Synthesis Pathways ndi Microstructural Design
2.1 Njira Zachikale komanso Zapamwamba Zopangira
Kaphatikizidwe ka taxi yoyera kwambiri sikisi nthawi zambiri imaphatikizapo mayankho olimba pakati pa calcium ndi boron precursors pa kutentha kokwera..
Njira zodziwika bwino zimaphatikizapo kuchepa kwa calcium oxide (CaO) ndi boron carbide (B ₄ C) kapena boron yofunika pansi pa inert kapena vacuum milingo pa kutentha pakati 1200 °C ndi 1600 °C. ^
. Yankho liyenera kuyendetsedwa bwino kuti apewe kupanga magawo owonjezera monga taxicab four kapena taxicab TWO., zomwe zimatha kusokoneza magwiridwe antchito amagetsi ndi makina.
Njira zina zimakhala ndi kuchepa kwa carbothermal, kusungunuka kwa arc, ndi mechanochemical synthesis pogwiritsa ntchito mphero yamphamvu kwambiri, zomwe zingachepetse kutentha kwakuya komanso kukulitsa homogeneity ya ufa.
Kwa zigawo za ceramic zowuma, sintering njira monga kutentha kukanikiza (HP) kapena kuyambitsa plasma sintering (SPS) amagwiritsidwa ntchito kukwaniritsa kachulukidwe kakang'ono pomwe akuchepetsa kukula kwa tirigu ndikusunga ma microstructures akulu.
SPS, makamaka, zimapangitsa kuti zitheke kuphatikizika mwachangu pazitentha zotsika komanso nthawi zazifupi zokhala, kuchepetsa chiopsezo cha calcium volatilization ndikusunga stoichiometry.
2.2 Doping and Issue Chemistry for Home Kusintha
Chimodzi mwazinthu zopambana kwambiri mu kafukufuku wa CaB ₆ ndi kuthekera kosintha malo okhalamo a digito ndi thermoelectric kapena malonda ndi doping mwadala komanso uinjiniya wopanda cholakwika..
Kusintha kwa calcium ndi lanthanum (The), cerium (Ce), kapena zinthu zina zosowa zapadziko lapansi zimabweretsa omwe amapereka ndalama zowonjezera, kumapangitsa kuti magetsi aziyenda bwino ndikupangitsa kuti zitheke kuchitapo kanthu pamtundu wa n-thermoelectric.
Mofananamo, Kusintha pang'ono kwa boron ndi kaboni kapena nayitrogeni kumatha kusintha makulidwe a mayiko pafupi ndi mulingo wa Fermi, kukulitsa mtengo wa Seebeck ndi chiwerengero chonse cha thermoelectric (ZT).
Mavuto achilengedwe, makamaka ntchito za calcium, zimagwiranso ntchito yofunikira pakuzindikira madulidwe.
Kafukufuku wofufuza akuwonetsa kuti ma taxi asanu ndi limodzi nthawi zambiri amawonetsa kuchepa kwa calcium chifukwa cha kusinthasintha nthawi yonse yotentha kwambiri, kumabweretsa kuwongolera kwa dzenje ndi zochita za mtundu wa p mu zitsanzo zina.
Kuwongolera stoichiometry kudzera pakuwongolera koyenera komanso kutsekeka panthawi ya kaphatikizidwe ndichifukwa chake ndikofunikira kuti muzitha kubwezanso bwino pakugwiritsa ntchito digito ndikusintha mphamvu..
3. Katundu Wothandiza ndi Phantasm Yathupi mu Taxi ₆
3.1 Ma Electron Discharge and Field Discharge Application
CaB ₆ imadziwika chifukwa cha ntchito zake zochepa– pafupifupi 2.5 eV– m'gulu la zinthu zotsika mtengo kwambiri za ceramic zokhazikika– kuzipanga kukhala phungu wapadera kwa thermionic ndi dera electron emitters.
Malo okhalamo kapena malondawa amapezeka kuchokera pakusakanikirana kwa ma elekitironi apamwamba kwambiri komanso makonzedwe opindulitsa a dipole, kupangitsa kuti ma elekitironi atuluke bwino pamiyezo yocheperako yotentha poyerekeza ndi zinthu wamba monga tungsten (ntchito ntchito ~ 4.5 eV).
Chifukwa cha izi, TAXICAB SIX-based cathodes amagwiritsidwa ntchito pazida zama elekitironi, kuphatikiza magalasi a electron microscopic (CHITI), zowotcherera ma electron, ndi machubu a microwave, kumene amapereka moyo wautali, kuchepetsa kutentha kwa ntchito, ndi kuwala kwambiri kuposa emitters ochiritsira.
Nanostructured taxi yamakanema asanu ndi limodzi ndi tsitsi zimakulitsanso magwiridwe antchito pokweza kulimba kwa dera lamagetsi pamalingaliro akuthwa., kupangitsa kuti zitheke kugwira ntchito koziziritsa kwa cathode mu ma microelectronics otsuka vacuum ndi zowonetsera zowonekera.
3.2 Mayamwidwe a Neutron ndi Kuteteza Ma radiation
Kuthekera kowonjezereka kwa CaB ₆ kwagona pakuyamwa kwake kwa neutron., makamaka chifukwa cha kuchuluka kwa matenthedwe a neutroni kuphatikizika kwa ¹⁰ B isotopu (3837 nkhokwe).
Natural boron imakhala ndi zokhudzana 20% ¹⁰ B, ndi zowonjezera za CaB zisanu ndi chimodzi zokhala ndi ¹⁰ B zokulirapo zitha kupangidwira kuti zitetezedwe bwino ndi neutroni.
Pamene neutroni imajambulidwa ndi ¹⁰ B nyukiliyasi, imayambitsa nyukiliya ¹⁰ B(n, a)⁷ Li, kutulutsa ma alpha particles ndi ma lithiamu ion omwe amayimitsidwa mosavuta mkati mwazinthuzo, kusintha ma radiation ya nyutroni kukhala tizidutswa topanda vuto lililonse.
Izi zimapangitsa taxi ₆ kukhala chinthu chowoneka bwino chazinthu zomwe zimayamwa ma neutroni muzomera zamagetsi zamagetsi., Invested gasi yosungirako, ndi machitidwe ozindikira ma radiation.
Mosiyana ndi boron carbide (B ₄ C), zomwe zimatha kutupa ndi kuwala kwa neutroni chifukwa cha kuchuluka kwa helium, CaB ₆ ikuwonetsa chitetezo chapamwamba komanso kukana kuwonongeka kwa ma radiation, makamaka pa kutentha kokwera.
Kusungunuka kwake kwakukulu komanso kukhazikika kwa mankhwala kumawonjezeranso kuthekera kwake kuti athe kutumizidwa kwa nthawi yayitali m'malo a nyukiliya..
4. Ma Arising and Industrial Applications mu Advanced Technologies
4.1 Kutembenuka kwa Mphamvu ya Thermoelectric ndi Kubwezeretsa Kutentha kwa Zinyalala
Kuphatikiza kwapamwamba kwamagetsi amagetsi, Mtengo wapakati wa Seebeck, ndi kuchepetsa matenthedwe madutsidwe (chifukwa cha kufalikira kwa phonon ndi maziko a boron) zoikamo CaB ₆ ngati chida cholonjeza cha thermoelectric chida- kukolola mphamvu zotentha kwambiri.
Mitundu yosiyanasiyana, makamaka La-doped taxi SIX, awonetsa mtengo wa ZT kuposa 0.5 ku 1000 K, ndi mphamvu zowonjezera zambiri kudzera mu nanostructuring ndi kapangidwe ka malire a tirigu.
Zogulitsazi zikupezeka kuti zigwiritsidwe ntchito m'majenereta a thermoelectric (Zithunzi za TEG) zomwe zimatenthetsa zinyalala zowopsa– kuchokera ku makina otenthetsera zitsulo, machitidwe otopa, kapena magetsi– mu mphamvu zamagetsi zothandiza.
Chitetezo chawo mumpweya komanso kukana okosijeni pamatenthedwe okwera amapereka mwayi wochulukirapo kuposa ma thermoelectrics achikhalidwe monga PbTe kapena SiGe., zomwe zimafuna mlengalenga woteteza.
4.2 Zopaka Zapamwamba, Zophatikiza, ndi Quantum Material Platforms
Mapulogalamu ambiri am'mbuyomu, TAXICAB ₆ ikuphatikizidwa muzinthu zophatikizika ndi zigawo zothandiza kuti zikhale zolimba, kuvala kukana, ndi mawonekedwe a electron kutulutsa.
Mwachitsanzo, TAXI SIX-yowonjezera kulemera kwa aluminiyamu kapena matrix amkuwa amawonetsa kulimba mtima komanso chitetezo chamatenthedwe pazamlengalenga ndi kugwiritsa ntchito magetsi..
Makanema owonda a taxi asanu ndi limodzi omwe amasamutsidwa kudzera pa sputtering kapena pulsed laser deposition amagwiritsidwa ntchito mu zokutira zolimba., zopinga zofalitsa, ndi zigawo zotulutsa mpweya mu vacuum digito zida.
Zowonjezera posachedwa, makhiristo amodzi ndi makanema opitilira muyeso a taxi zisanu ndi chimodzi adakopa chidwi ndi fizikisi yofupikitsidwa chifukwa cha mbiri yamakhalidwe osayembekezereka., opangidwa ndi zonena za kutentha kwachipinda ferromagnetism mu zitsanzo doped– ngakhale izi zikupitilira kukhala zokayikitsa ndipo mwina zimalumikizidwa ndi chilema choyambitsa maginito m'malo mwa dongosolo lakutali..
Osatengera, CaB ₆ imagwira ntchito ngati njira yowerengera zotsatira za kulumikizana kwa ma elekitironi, Topological digital states, ndi kayendedwe ka quantum mu zovuta za boride latticeworks.
Powombetsa mkota, calcium hexaboride ndi chitsanzo chophatikizika cha kulimba kwa zomangamanga komanso kuphweka kwazinthu zama ceramics apamwamba..
Kusakanikirana kwake kwapadera kwa madutsidwe apamwamba amagetsi, kukhazikika kwamafuta, kuyamwa kwa neutron, ndi ma elekitironi emission okhalamo kapena malonda katundu amalola ntchito kudutsa mphamvu, nyukiliya, zamagetsi, ndi mayina amadomeni asayansi yazinthu.
Pamene kaphatikizidwe ndi njira za doping zikupita patsogolo, CaB ₆ imayikidwa kuti igwire ntchito yofunika kwambiri muukadaulo wam'badwo wotsatira womwe ukufunika kugwira ntchito bwino pazovuta kwambiri..
5. Wopereka
TRUNNANO ndi ogulitsa Spherical Tungsten Powder yokhala ndi over 12 zaka zambiri zachitetezo cha nano-building energy komanso chitukuko cha nanotechnology. Imavomereza kulipira kudzera pa Kirediti kadi, T/T, West Union ndi Paypal. Trunnano idzatumiza katundu kwa makasitomala kunja kwa FedEx, DHL, ndi mpweya, kapena panyanja. Ngati mukufuna kudziwa zambiri za Spherical Tungsten Powder, chonde omasuka kulankhula nafe ndi kutumiza kufunsa([email protected]).
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