Tau qhov twg los: news.northwestern.edu
Cov kev tshawb pom, luam tawm hnub no (Kaum Ib Hlis 17) hauv phau ntawv Journal Science, piav qhia txog kev daws teeb meem dual-molecule kom kov yeej kev poob hauv kev ua haujlwm zoo li lub hnub ci hloov mus rau lub zog. Los ntawm kev sib koom ua ntej, ib lub molecule los hais txog ib yam dab tsi hu ua nto recombination, nyob rau hauv uas electrons ploj thaum lawv raug daig los ntawm qhov tsis xws luag - uas ploj lawm atoms ntawm qhov chaw, thiab ib tug thib ob molecule los cuam tshuam recombination ntawm lub interface ntawm cov khaubncaws sab nraud povtseg, pab neeg no ua tiav lub National Renewable. Energy Lab (NREL) tau lees paub qhov ua tau zoo ntawm 25.1% qhov kev ua ntej dhau los mus txog qhov ua tau zoo ntawm 24.09%.
"Perovskite hnub ci thev naus laus zis tau txav ceev ceev, thiab qhov tseem ceeb ntawm kev tshawb fawb thiab kev txhim kho yog hloov pauv los ntawm cov khoom nqus nqus mus rau qhov sib cuam tshuam," said Northwestern xibfwb Ted Sargent. "Qhov no yog lub ntsiab lus tseem ceeb los txhim kho kev ua tau zoo thiab kev ruaj ntseg thiab coj peb los ze zog rau txoj kev cog lus no kom muaj txiaj ntsig zoo dua hnub ci."
Sargent yog tus thawj coj ua haujlwm ntawm Paula M. Trienens lub koom haum rau Sustainability thiab Zog (yav tas los ISEN) thiab tus kws tshawb fawb ntau yam hauv cov ntaub ntawv chemistry thiab lub zog, nrog rau kev teem sijhawm hauv chav haujlwm ntawm chemistry hauv Weinberg College of Arts thiab Sciences thiab department ntawm hluav taws xob thiab computer engineering hauv McCormick School of Engineering.
Cov pa hluav taws xob hnub ci yog ua los ntawm cov khoom siv siab dawb huv silicon wafers uas muaj lub zog siv los tsim thiab tsuas tuaj yeem nqus tau ntau yam ntawm lub hnub ci spectrum.
Perovskite cov ntaub ntawv uas nws qhov loj thiab muaj pes tsawg leeg tuaj yeem hloov kho rau "tune" lub wavelengths ntawm lub teeb uas lawv nqus tau, ua rau lawv muaj txiaj ntsig zoo thiab muaj peev xwm qis dua, kev ua haujlwm siab tawm tandem thev naus laus zis.
Keeb kwm perovskite hnub ci hlwb tau plagued los ntawm cov kev cov nyom los txhim kho efficiency vim lawv cov txheeb ze instability. Ob peb xyoos dhau los, kev nce qib los ntawm Sargent's lab thiab lwm tus tau coj qhov ua tau zoo ntawm perovskite hnub ci hlwb mus rau hauv tib thaj tsam li qhov ua tiav nrog silicon.
Hauv kev tshawb fawb tam sim no, tsis yog sim pab lub cell nqus hnub ci ntau dua, pab pawg tau tsom mus rau qhov teeb meem ntawm kev tswj hwm thiab khaws cov khoom tsim hluav taws xob kom ua tau zoo. Thaum lub perovskite txheej hu rau electron thauj txheej ntawm tes, electrons txav ntawm ib qho mus rau lwm qhov. Tab sis cov hluav taws xob tuaj yeem txav mus rau sab nraud thiab sau, lossis "recombine" nrog cov qhov uas muaj nyob rau ntawm txheej perovskite.
"Kev sib koom ua ke ntawm kev sib txuas yog qhov nyuaj," said thawj tus sau Cheng Liu, tus tub ntxhais kawm ntawv qib siab hauv Sargent lab, uas yog tus saib xyuas los ntawm Charles E. thiab Emma H. Morrison xibfwb ntawm Chemistry Mercouri Kanatzidis. "Nws yog ib qho nyuaj heev los siv ib hom molecule los daws qhov nyuaj recombination thiab khaws cov electrons, yog li peb tau txiav txim siab seb qhov sib xyaw ntawm cov molecules peb tuaj yeem siv los daws qhov teeb meem ntau dua."
Cov kev tshawb fawb yav dhau los los ntawm Sargent pab pawg tau pom cov pov thawj tias ib qho molecule, PDAI2, ua haujlwm zoo ntawm kev daws teeb meem kev sib txuas. Tom ntej no lawv yuav tsum nrhiav ib lub molecule uas yuav ua hauj lwm los kho qhov tsis xws luag thiab tiv thaiv electrons los ntawm recombining nrog lawv.
Los ntawm kev nrhiav cov txheej txheem uas yuav tso cai rau PDAI2 ua haujlwm nrog cov molecule thib ob, pab pawg tau nqaim nyob rau hauv cov leej faj, uas tuaj yeem hloov cov pa roj carbon pawg - feem ntau tsis zoo ntawm kev tiv thaiv electrons los ntawm kev txav mus los - los npog cov atoms uas ploj lawm thiab suppress recombination.
"Nyob rau hauv hais txog qhov tseem ceeb inefficiencies pom nyob rau hauv inverted perovskite solar cells, uas yog feem ntau vim nonradiative recombination poob, tus qauv tshiab nyob rau hauv lub hnub ci cell efficiency yog teem," said Northwestern professor Mercouri Kanatzidis. "Qhov no yog ib qho piv txwv tseem ceeb ntawm yuav ua li cas lub teb ntawm cov ntaub ntawv qib siab chemistry tuaj yeem txhim kho lub zog hloov dua siab tshiab thiab ua kom ntev ntawm cov thev naus laus zis perovskite photovoltaic."
Kanatzidis yog ib tug thawj coj nyob rau hauv lub teb ntawm cov ntaub ntawv chemistry thiab sustainable zog kev daws teeb meem, nrog rau ob lub sij hawm nyob rau hauv Weinberg lub department ntawm chemistry thiab McCormick lub department ntawm cov ntaub ntawv science thiab engineering.
"Peb zoo siab tias peb lub tswv yim bimolecular qhia tau hais tias muaj feem xyuam rau ntau yam perovskite compositions, nrog rau cov uas tau cog lus rau tandem hnub ci hlwb," said Bin Chen, kws tshawb fawb pab xibfwb ntawm chemistry thiab tus kws sau ntawv rau ntawm daim ntawv.
Ib daim ntawv tsis ntev los no los ntawm tib pab pawg tau luam tawm hauv Nature tau tsim cov txheej txheem rau lub substrate hauv qab txheej perovskite los pab cov cell ua haujlwm ntawm qhov kub siab dua rau lub sijhawm ntev. Qhov kev daws teeb meem no, raws li Liu, tuaj yeem ua haujlwm nrog cov kev tshawb pom hauv daim ntawv Science.
Txawm hais tias pab pawg vam tias lawv qhov kev tshawb pom yuav txhawb nqa lub zej zog kev tshawb fawb loj dua kom txuas ntxiv mus ua haujlwm rau yav tom ntej, lawv kuj tseem yuav ua haujlwm rau kev taug qab.
"Peb yuav tsum siv lub tswv yim hloov tau yooj yim dua los daws qhov teeb meem cuam tshuam nyuaj," Cheng hais. "Peb tsis tuaj yeem siv ib hom molecule nkaus xwb, ib yam li tib neeg yav dhau los tau ua. Peb siv ob lub molecules los daws ob hom kev rov ua dua tshiab, tab sis peb paub tseeb tias muaj ntau hom kev cuam tshuam cuam tshuam txog kev sib txuas ntawm lub interface. Peb yuav tsum sim siv. ntau molecules los ua ke thiab xyuas kom meej tias tag nrho cov molecules ua haujlwm ua ke yam tsis muaj kev puas tsuaj rau ib leeg lub luag haujlwm. "
