
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 Abaqumi: 
 
 
 
 
 
 
 
 
 
 
 
 
 
 UMeho Lee UMe-Hee Han UMin-Ho Park UDae Yool Jung UJeongmin Seo UHong-Kyu Seo UHyunsu Cho UEunhye Kim UJin Chung USung-Yool Choi UTaek-Soo Kim UTae-Woo Lee USeunghyup Yoo Isishwankathelo I-Graphene-based organic light-emitting diodes (OLEDs) sele ive kamsasa njengento ephambili efunekayo kwizikrini ezizukulwana ezizayo kunye nezibane, ikakhulu ngenxa yesithembiso sayo seemithombo zokukhanya eziguquguqukayo. Nangona kunjalo, ukusebenza kwayo kube, kungcono kakhulu, kufana nokwezo ziqhelekileyo, ezenziwe nge-indium tin oxide. Sicebisa isicwangciso se-electrode esiphambili esenziwe ngokusekelwe kudlala oludibanayo lwezikhondo ze-TiO2 eziphezulu kunye nezikhondo zokujova iihole ezisezantsi ezijinga ii-electrode zegraphene, nto leyo evelisa imeko efanelekileyo apho ukuphucuka ngenxa yerhombus ye-cavity kuphakame kakhulu kodwa ilahleko kwi-surface plasmon polariton ihla. Indlela enikeziweyo ikhokelela kwi-OLEDs ezibonisa ukusebenza okuphezulu kakhulu kwangaphandle kwe-quantum efficiency ye-40.8 kunye ne-62.1% (i-64.7 kunye ne-103% kunye nelensi ye-half-ball) kwizixhobo eziphindwe kabini nezininzi, ngokulandelelanayo. I-OLEDs eyenziwe kwiipolima kunye nezi-electrode zinokubuyiselwa umva kwakhona kwi-radius ye-2.3 mm, ngokuyinxenye ngenxa ye-TiO2 ezimelana nokudandatheka okufika kuma-4% ngokuphulukisa uqhekeko lwesikhuni. Intshayelelo Iingenelo zesimo njengokuguquguquka kunye nokunwebeka ziye zagxininisa ii-organic light-emitting diodes (OLEDs) umdla omkhulu ekusetyenzisweni kwizixhobo ezivelayo ezifana nezikrini ezinokunxitywa, ezingatywiniweyo okanye ezingatyumayo ezifuna ukuhamba, ukuguquguquka kunye/okanye ukwanda , . Ukuzaliseka ngokupheleleyo kwesi sakhono, nangona kunjalo, akulula kwaye kufuna umzamo omkhulu kwiinkalo ezahlukeneyo njengokwakhiwa kweetecknoloji ze-thin-film transistor ezisemgangathweni kunye/okanye ukugquma okuguquguqukayo . Enye inkalo ebalulekileyo ekufuneka iqwalaselwe kwezi zibonisi zigquguqukayo kukufumana ii-electrode ezibonakalayo (TEs) ezingathatha indawo ii-electrode ze-indium tin oxide (ITO), eziqhele ukuba neengxaki zokuguquguquka okulinganiselweyo kunye neengxaki zeendleko ezinokubakho ezinxulumene nemfuno ephezulu kunye/okanye ukubonelela okungazinzanga . Ngeli cala, iintlobo ezininzi ii-electrode eziguquguqukayo ezibonakalayo ezifana ne-metal nanowires, izinto eziyigraphene (umzekelo, i-carbon nanotubes okanye igraphene) kunye ne-metal grids edityaniswe nezinye iintlobo ze-TEs ziye zazanywa kwi-OLEDs , , , , , . Phakathi kwazo, igraphene—iqweqwe elincinci eliyi-atom eli-sp2-hybridized carbon atoms—iye yajongwa njengeyona ithembisayo kuba ukudibanisa kwayo okukhethekileyo kobuncinci bayo kunye nemisebenzi yayo yombane ephucukileyo kulindeleke ukuba ivumele ii-electrode ezibonakalayo eziye zine-haze encinci okanye engabonakaliyo, indawo enee-smooth ezithintela ukugqabhuka kombane okubangelwa kukugruzuka kunye nokubola, ukudluliselwa okuphezulu, ukumelana nomgca ophantsi kunye nobuninzi bokuguquguquka bonke ngaxeshanye , . Ukulungiswa ngokulula kwegraphene esemgangathweni kumacandelo eepolima omkhulu asebenza njengama-electrode abona kude uye waboniswa ngeendlela ezithintelayo ukuba zenziwe kwishishini, zibonisa ukusebenza kwazo , . Zombini i-single-layer graphene (SLG) kunye ne-multi-layer graphene (MLG) ziye zabonakaliswa njengefanelekileyo kwi-TEs kwi-OLEDs , . Ngokukodwa, i-OLEDs ezisebenza kakuhle ezisekelwe kwigraphene ziye zafunyanwa ngoncedo lwezikhondo zokujova iihola (HILs) ezisetyenziselwa ukugqitha umsebenzi wazo ophume kancinci, owaziwa ngokuba malunga nama-4.5 eV. Ezi zikhondo zokujova zibandakanya ii-polymers eziqhuba ngokudlala iimpawu zombane ezinje nge-self-organized gradient HIL (GraHIL) , kunye nezikhondo ezincinci ze-buffer ze-MoO3 ezidibene ne-polymers eziqhuba ngokubizwa ngokuba yi-poly(3,4-ethylenedioxythiophene): polystyrene sulfonate (PEDOT:PSS) . Nangona kunjalo, ukusebenza kwamandla kunye nokusebenza okuphezulu kwe-quantum efficiency (EQE) kwezi-OLEDs zangoku ezenziwe ngegraphene zazisenje ngezo ze-OLEDs ezisekelwe kwi-ITO, ngaphandle kokuba kusetyenziswe ilensi enkulu ye-hemispherical ukunyusela ukuphuma . Ukufumana ukusebenza okuphezulu kangangoko kubaluleke kakhulu kwiimboniso eziphumelelayo ezisetyenziswa kwizicelo eziphathwayo okanye ezinokunxitywa, njengoko zihlala zixhomekeke kubatshaji bamanqanaba amandla alinganiselweyo ngenxa yezithintelo kubungakanani, ubunzima okanye iifom zemveli. Oku kufuna ukwakhiwa kwesicwangciso sesixhobo esinokukhulisa ukusebenza kwe-OLEDs ezisekelwe kwigraphene. Ingxaki ephambili kukwakha isakhiwo okanye indlela yokukhupha amandla ayo apheleleyo okubonisa ngelixa kugcinwa iingenelo zegraphene kwiifom zemveli kangangoko kunokwenzeka. 1 2 3 4 4 5 6 7 8 9 10 11 11 12 13 14 13 14 14 Ngoku, sihlola isicwangciso se-electrode esilula esisekelwe kwizikhondo ze-TiO2 eziphezulu kunye ne-HILs ezisezantsi ezijinga ii-electrode zegraphene. Ngokuyilwa okubonisa ukuxhamla ngokupheleleyo kubudlelane obudibeneyo phakathi kwezikhondo eziphezulu nezisezantsi ezilawula kokubini ukuphakanyiswa kwe-cavity resonance kunye nelahleko kwi-surface plasmon polariton (SPP), ii-OLEDs ezisekelwe kwigraphene ezicetyiswayo zibonisa i-EQE ephezulu kakhulu engazange ibonwe kwabo basebenzisa igraphene njenge-electrode ebonakalayo. Ngaphezu koko, ukumelana okuphezulu okungaqhelekanga kwe-TiO2 ekudandathekeni okuguquguqukayo kuyavezwa okuvumela i-OLEDs eziye zingagcini nje ngokusebenza kodwa zikwagquguquka kakhulu. Iziphumo Uyilo olubonakalayo lwee-OLEDs ezisebenza kakhulu ezisekelwe kwigraphene Ukusebenza kwe-OLEDs kulinganiselwa ngokupheleleyo kukwandiswa kokukhutshwa okungaphandle okungaqhelekanga okungama-20% kungcono kwizixhobo ezine-isotropic emitters. Phakathi kwezicwangciso ezahlukeneyo zokuphuculwa kokukhutshwa okuye zazanywa ukuza kuthi ga ngoku , indlela esekelwe kwi-microcavity resonance inezinzuzo njengoko igcina uyilo oluyicaba ngaphandle kokusebenzisa naluphi na uqeqesho lwe-micro/nano okanye isicwangciso se-lenticular ukuze ii-OLEDs ezenziwe ngayo zingabonakali kuzo izinto ezimfutshane zombane kunye nezinto zokubonisa ezingafunekiyo kwisicelo sesibonisi (umzekelo, ukudikiza, i-diffraction nokunye) kodwa zinokubonisa imibala eyamkelekileyo, egcwele kakhulu ebomvu (R), eluhlaza (G), eluhlaza okwesibhakabhaka (B) kunye nokusebenza okuphezulu , . Ngomphumo omncinci kodwa osondele ngakumbi we-microcavity, ii-OLEDs ezisekelwe kwi-ITO zinokulungiswa ngokupheleleyo ukuze zisebenze kakhulu, ngaphandle kokuba kube kukhona naluphi na uhlobo lokudikiza okanye ukudikiza, ngokulungisa nje ubukhulu bezikhondo ze-ITO; kwesi sicwangciso, isicwangciso se-cavity se-first-order, i-3 /4, apho i-  imele ubude bolwandle, sifumaneka kunye nesiphelo esivulekileyo semowudi ye-cavity esekwe kubudlelwane be-ITO/substrate , . Kwimeko ye-OLEDs ezisekelwe kwigraphene, nangona kunjalo, ii-electrode zegraphene azikwazi ukwenziwa zibe zinzima ngokwaneleyo ukulawula ubude be-cavity, nto leyo eyenza kube nzima ukuphucula ukusebenza ngomphumo we-resonance . 15 16 17 λ λ 18 19 20 Njengenye indlela, umntu unokubeka isikhondo esine-refractive index ephezulu ( H) phantsi kwee-electrode zegraphene njengoko kuboniswe ku   ngendlela efana nezikhondo zethayile ezinyibilikisiweyo ezenziwe nge-metal , , , . Ngokuba ukukhanya kunokudlula kwigraphene ngohluko oluncinci lwe-phase ngenxa yobuncinci bayo besikhondo segraphene, isicwangciso se-3 /4 cavity sinokufumaneka ngokulula, umzekelo, kunye nobude bolwandle obubonakalayo besikhondo se-organic kunye nesokujova kunye nesikhondo esine-refractive index ephezulu esibekwe malunga ne-2 /4 kunye ne- /4, ngokulandelelana ( ). Ngokukodwa, isikhondo esine-index ephezulu esiyi-‘ /4-thick’ sikwanjenge-metal-free, i-dielectric mirror evumela ukubonisa okubalulekileyo ukusuka kwindibano ye-electrode engezantsi ( bot) kukhanyiso olungena ukusuka kwizikhondo zangaphakathi, njengoko kunokuthi kuqinisekiswe kumagrafu abonisiweyo ezantsi kwe  . Oku kunika ii-OLEDs ezisekelwe kwigraphene amathuba okuphucula ukusebenza kwazo ngokusebenzisa umphumo we-resonance, nto leyo ebengayi kwenzeka ngolunye uhlobo. Kubonisiwe ukuba i- bot kunye nokuphakama kwe-resonance okuphumelelayo kuyanda kunye ne- H ( ). I-index ephezulu ikwanemveliso ngokubhekiselele ekuguquguqukeni njengoko ubukhulu bolwandle obujolisiweyo ( H H) bungafunyanwa kunye nobukhulu obuncinci obubalulekileyo  H, kwaye kuba uqhekeko olubangelwa kukuqhekeka kwefilimu ethile ludla ngokubakho kwinqanaba eliphantsi kokuqhekeka kunye nobukhulu obubalulekileyo . Isikhondo esiphumeleleyo esine-index ephezulu kwesi sicwangciso kufanele sibe ne- H enkulu kangangoko kunokwenzeka. Ngaphezu koko, kufanele ibe yeyona, kwaye ngaphezu kwako konke, akufanele yonakaliswe yindlela yokudlulisa i-graphene. Phakathi kwezinto ezahlukeneyo ezingafunyenwayo, isikhondo se-TiO2 esidonsweyo sibonakalisa uluhlu olubonakalayo kwaye sine-refractive index ephezulu ( =2.5). Ngokungafani nezinye izikhondo eziphezulu esiye sazama, isikhondo se-TiO2 sigqiba ukuba sinokumelana nekhemikhali okunamandla ngokuchasene neendlela zokudlulisa i-graphene ezisebenzisa isinyibilikisi, njenge-acetone okanye i-isopropyl alcohol (IPA), okuvumela ukubunjwa kwe-electrode ye-graphene esemgangathweni phezu kwayo ( ). n Umz. 1a 17 20 21 22 λ λ λ Umz. 1b λ R Umz. 1c,d R n Supplementary Fig. 1 n d d 23 n n Supplementary Fig. 2   ( ) Isakhiwo sesixhobo sesicwangciso see-OLEDs ezicetyiswayo. ( ) Ukusasazeka kobukhulu be-electromagnetic field (imigca etyibilayo) ye-OLEDs ezichongiweyo kucwangciso lwazo lwe-cavity lokuqala. Ukusasazeka kobukhulu be-field ye-OLEDs ezisekelwe kwigraphene ngaphandle kwe-TiO2 kuboniswe kwakhona ukuze kuqhathaniswe kwiimeko apho ubukhulu bezikhondo ze-organic zifana neze-OLEDs kunye ne-TiO2 kodwa ngaphandle kwe-HILs ezisezantsi. ( , ) I-external quantum efficiency ebalelweyo ( EQE) ye-OLEDs ezisekelwe kwigraphene kunye nesikhondo se-TiO2 njengomsebenzi wobukhulu be-TiO2 kunye nesikhondo se-organic ( TiO2 kunye  org, ngokulandelelanayo). Imigca etyibilayo imele imigca ye-contour ye- EQE ye-10, 20, 30 okanye 40% njengoko ibonisiwe kumzobo. ( ) Ngaphandle kwe-HIL ephantsi; ( ) kunye neGraHIL njenge-HIL ephantsi. Ezantsi kwityala ngalinye, ukubonisa ( bot) ukusuka kwindibano ye-electrode engezantsi (TiO2/graphene/(HIL)) ngokubanzi kuboniswe njengomsebenzi we- TiO2 kukhanyiso olungena kwi-organic layers. a b c d η d d η c d R d Kubalulekile ukuthi isicwangciso se-micro-cavity esiphezulu (umzekelo, i-order yesibini, i-5 /4 cavity) esisekelwe kwisikhondo esinzima se-organic kunokwenzeka. Kulo msebenzi, nangona kunjalo, isicwangciso se-cavity sokuqala sikhethwa kuqala kuba sibangela i-Purcell effect enamandla kwaye sincinci i-waveguide modes kune-design ye-order ephezulu, ekugqibeleni ikhokelela ekwandisweni kokukhutshwa kunye ne-EQE , . Iingxaki zisabakho kwisicwangciso se-cavity sokuqala kuba indawo efanelekileyo yendawo yokukhutshwa ilingiselwe kwi-antinode yokuqala ukusuka kwindawo ye-organic/metal, yenze kube nzima ukunciphisa i-SPP modes ngokwandisa umgama womthumisi ukuya kwii-metal , . Indlela enye esetyenziswa rhoqo ukunciphisa i-SPP kukufaka uyilo olungaphakathi olugudluzelayo okanye i-corrugations , kodwa ukuthwala ukufutshwa kombane kunokuba ngumngeni ngezi ndlela. Indlela esiyisebenzisayo apha kukufaka isikhondo esine-index ephantsi, esiye sabonakaliswa njengesinciphisa ngokufanelekileyo i-SPP modes , . Ngokuthamsanqelayo, i-GraHIL okanye i-self-organized gradient hole-injection layer equkethe i-PEDOT:PSS kunye ne-tetra-fluoroethylene-perfluoro-3, 6-dioxa-4-methyl-7-octenesulphonic acid copolymer (PFI), eyayicetyiswe ngaphambili ngababhali kwaye yabonisa ukuba iyasebenza kakhulu ekuphuculeni ukujova ihola kwi-OLEDs ezisekelwe kwigraphene , inee-refractive index ezimalunga ne-1.42 kwi-  ye-550 nm ( ), nto leyo ephantsi kakhulu kunezo zezikhondo eziqhelekileyo zangaphakathi ( =1.8). Ngobudlelwane obudibeneyo bezikhondo eziphezulu neziphantsi ezijinga izikhondo zegraphene, ukuphakanyiswa komphumo we-cavity-resonant kunye nokuncitshiswa kwe-SPP modes kunokwenziwa ngaxeshanye ukuze i-EQE iphakame kakhulu nangaphandle kwezicwangciso zokukhutshwa. λ 24 25 25 26 27 28 29 13 λ Supplementary Fig. 3 n  ubeka iziphumo zokulawulwa kwe-optical ngokusekelwe kumgangatho ophuculweyo weteyori ye-electromagnetic ebekwe nguFurno  .  kulo lonke uluhlu lwamaza okubonisa, kwaye kwi-  ye-550 nm. Ifomulo iqwalasela i-Purcell factor, umphumo wokuhlangana kwe-dipole, kunye nokukhuthazwa kwi-SPP kunye nemowudi ye-waveguide. Ukubandakanywa okupheleleyo kwezi mpawu zonke kubalulekile kuhlalutyo oluchanekileyo kunye nolwakhiwo olulinganiselayo njengoko ukutshona okungaphezulu okanye okungaphantsi kunokwenzeka xa kusetyenziswa indlela elula engaziyo okanye engabandakanyi enye okanye ngaphezulu kwezi mpawu (bona  ;   kunye   ngeemizekelo). Iziphumo zibonisa ukuba ukusetyenziswa kweGraHIL kuhlengahlula imibandela yamandla phakathi kweemowudi ezahlukeneyo ukuya kwi-wave vectors ezincinci ezidibanayo ukuze amandla ahambelana ne-SPP modes ancitshiswe kwaye amacandelo akhutshiweyo aphakanyiswe ngakumbi ( ). Kunokubonwa kwakhona kwi   ukuba ukusetyenziswa kwesikhondo se-TiO2 phantsi kwegraphene kunciphisa ngokufanelekileyo inqanaba lamandla ahambelana ne-waveguided kunye ne-substrate modes ngokuphakanyiswa kwe-resonance. Oku kukhokelela ekwandeni okubalulekileyo kokusebenza kokukhutshwa, nangona ilahleko kwimowudi ye-evanescent ikwaye ibonisiwe ukwanda ngenxa yokutshintsha kweemowudi ze-transverse-electric waveguide ukuya kwi-wave vectors ephezulu yeenqwelomoya ezingaphezulu ( ). Ukudibanisa ukusetyenziswa kwe-index ephezulu (H) i-TiO2 kunye ne-index ephansi (L) i-GraHIL, kuvelisa imeko efanelekileyo apho ukuphakanyiswa kwe-resonance kukukhulu, kodwa ilahleko kwi-SPP/evanescent modes ihla. Ukongeza, ukudibanisa ukusetyenziswa kudala imeko efana ne-HL-stacks, esetyenziselwa ukugquma kwefilimu ezininzi ezibonisa , kwaye uphakamise ngakumbi i- bot ( ), kuvumela ukuphakanyiswa okongeziweyo kumphumo we-Fabry–Perot resonance. Oko kwenza ubuchwepheshe obucetyisiweyo bube yingqayizivele kwaye buphuculwe ngokubhekiselele kubuchwepheshe obuqhelekileyo yiyo kanye ubudlelwane obudibeneyo bezi zikhondo eziphezulu nezisezantsi ezivumela ulawulo olubonakalayo kunye ne-SPP loss ukuze kuxhamle ukukhutshwa okuphezulu; kunye nokuphakanyiswa kwe-resonance okongeziweyo ngokusebenzisa ukudibanisa kwe-HL. Ngokudibanisa kunye neempawu zabo zombane ezifunekayo (umzekelo, ukujova ihola okusebenzayo), zonke ezi zinzuzo zokubonisa zivumela umntu ukuba avule ngokupheleleyo nangempela amandla afihliweyo ee-OLEDs eziyicaba ezinokubonelela ngazo. Iigrafu zomgca ezifunyenweyo zokusebenza okuphezulu kwe-EQE ( EQE (max)) njengomsebenzi wobukhulu be-organic ( org) kunye nobukhulu be-TiO2 ( TiO2) eziboniswe ku   zibonisa ukuba i- EQE (max) ingafikelela kuma-44% kwizixhobo kunye neGraHIL kunye nezikhondo ze-TiO2 ngelixa kungayikulinganiselwa kuma-38% ngaphandle kweGraHIL okanye kuma-31% ngaphandle kwe-TiO2. Iimeko eziphumeleleyo zijongana nemeko apho i- H (kunye no-H ebengu-TiO2) ilingana ne- /(4 H) (55 nm kwi- =550 nm). Kunokuthi kuqatshelwe kwakhona ukuba i- EQE (max) ye-44% iphakame kunezo kulindelekileyo kwi-optimized, ii-OLEDs ezisekelwe kwi-metal esele ikho kunye nomthumisi ofanayo. Oku kunokubangelwa yinyani yokuba ubume obucetyisiweyo buphantsi kokulahleka ngenxa yokufunxwa kwe-photon kunye/okanye ukukhuthazwa kwemowudi ye-SPP phakathi kwii-electrode ezibonakalayo (bona   kunye   ukuze kuqhathaniswa nezo ze-OLEDs ezisekelwe kwi-metal esele ikho). Umzobo 2a,b et al 19 λ Supplementary Fig. 4 Supplementary Table 1 Supplementary Note 1 Supplementary Fig. 5a Supplementary Table 2 Supplementary Fig. 5b 30 R Umz. 1d η d d Umz. 1c,d η d λ n λ η Supplementary Fig. 6 Supplementary Table 3   ( , ) Imiboniso yokusasazeka kwamandla okuchithwa kwamandla enobunzima kwisithonyama somthumisi ngamunye ngamunye (iboniswe njengombala ochazwe kwibarth ye-colour) ngokuchasene ne-in-plane wave vector: ( ) kunye ne-TiO2 kodwa ngaphandle kweGraHIL; ( ) kunye ne-TiO2 kunye neGra a b a b

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