
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 Ababhali: 
 
 
 
 
 
 
 
 
 
 
 
 
 In Hyuk Son Jong Hwan Park Soonchul Kwon Seongyong Park Mark H. Rümmeli Alicja Bachmatiuk Hyun Jae Song Junhwan Ku Jang Wook Choi Jae-man Choi Seok-Gwang Doo Hyuk Chang Isishwankathelo I-Silicon iyanconywa kakhulu njengento esebenzayo yeebhetri ze-lithium-ion zesizukulwana esilandelayo ngenxa yamandla ayo angafaniyo ngokobunzima. Nangona kunjalo, utshintsho olukhulu lwevolumu ye-silicon ngexesha lemijikelezo yokutshaja-ukukhupha yenza kube nzima ukuba ijongwe kumandla egolide avolumethric kunye nobomi bomjikelo. Apha sixela ukukhula okuthe ngqo kwe-graphene phezu kwe-silicon nanoparticles ngaphandle kokwakheka kwe-silicon carbide. Imilandelwana ye-graphene ehlanganiswe ngonxibelelwano nobuso be-silicon ijongana nokwanda kwevolumu ye-silicon ngokusebenzisa inkqubo yokushelela phakathi kwemigqabathi ye-graphene elandelanayo. Xa ibhangiswe ne-cathode ye-lithium cobalt oxide esetyenziswa rhoqo, i-graphene coating engenayo i-silicon carbide ivumela iseli epheleleyo ukuba ifikelele kumandla egolide avolumethric ye-972 kunye ne-700 Wh l−1 kwijikelo lokuqala kunye neye-200, ngokulandelanayo, i-1.8 kunye ne-1.5 amaxesha aphezulu kunee-bhetri ze-lithium-ion ezithandwayo ezisebenzisa kwilizwe lonke. Oku kubonisa ukuba indlela ye-graphene elihlalutya kwaye idityaniswe ne-silicon ngaphandle kwe-silicon carbide ingasebenza njengeprothotype ekuphuculeni ii-anode ze-silicon kuteknoloji esebenza ngezorhwebo. Intshayelelo Isakhono sobunzima esithathwa yi-silicon (Si) sifikelela malunga ne-4,000 mAh g−1. Eli xabiso alifaniyo lenze ukuba uluntu lweebhetri lutshale imali eninzi kwiingcinga zophando kuba isakhono sobunzima esiphezulu sivumela ukuphakama kwamandla eebhetri ze-lithium-ion (LIBs) kakhulu, kwaye ke ngoko lungenise izicelo ze-LIB zexesha elizayo, ezinjengeemoto zombane, ekubeni zenzeke , , , , . Kwiminyaka elishumi edlulileyo, iindlela ezahlukeneyo zesakhiwo sezixhobo , , , , , , , , , ,  kunye neenkqubo zokubopha , ,  zenziwa ukulungisa imiba yokulahleka kwesakhono ebalelwa ekutshintsheni okukhulu kwevolumu ye-Si, okukhokelele ekuphuculeni okubonakalayo kwintsebenzo yomjikelo nokuba kudala kwiinkulungwane zemijikelo . Ngaphandle kwexabiso elinokwethenjwa lobunzima kunye nenkqubela phambili ebalulekileyo kubomi bomjikelo, uninzi lwe-anode ye-Si eyenziwe kude kube ngoku luye lwagxila ikakhulu kwisakhono sobunzima kodwa aluzange lunikezele ngesithembiso esifanayo kwisakhono salo samandla egolide kuba iikhethithi zesixhobo ezikhoyo ziyasebenza ngokusekelwe kwindawo evulekileyo echaziweyo ukwamkela ukwanda kwevolumu ye-Si. Kwiinkqubo ezininzi ze-LIB kubandakanya izixhobo eziphathwayo, nangona kunjalo, amandla egolide avolumethric yinto ebalulekileyo ekumiseni intsebenzo yebhetri. Kunye nobomi bomjikelo obungekho kakuhle, amandla egolide aphantsi avolumethric ngoku yingxaki enkulu ekusebenziseni ii-anode ze-Si kwiiseli zorhwebo. Ukuhlangabezana nale mfuno ebalulekileyo, iteknoloji ye-anode ye-Si kufuneka ihlolwe ngokutsha ngeekhethithi zesixhobo ezahlukeneyo ezibonelela ngentsebenzo yokujikeleza ezinzileyo ngelixa ivolumu yesixhobo incitshiswa. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 11 Nangona iimorphologies ezahlukeneyo ze-Si kunye nezikhompawundi zazo kunye nezinye izinto eziqhuba uombane ziyafumaneka ngoku, esisombululo esikhawulezileyo kwimveliso yokwenyani efuna ulawulo lomgangatho ophezulu, imveliso elula kunye ne-scalable yezinto ze-Si ezisebenzayo ibalulekile. Ukusuka kwindawo yokubona usetyenziso, phakathi kwenani elikhulu labagqatswa abanokwenzeka, ukusetyenziswa kwe-silicon nanoparticles (NPs) zorhwebo kunye ne-coating enganyelayo yokukhusela ubuso iya kuba yinto efanelekileyo kakhulu. Izinto ezahlukeneyo eziqhuba uombane kubandakanya i-carbon emileyo (AC) ziye zavavanywa njengezinto zokugubungela ii-anode ze-Si NP , , . Nangona kunjalo, uninzi lwazo luyasilela ukubonelela ngentsebenzo yokujikeleza ixesha elide elizinzileyo kuba izinto zokugubungela ezisetyenzisiweyo azikwazi ukwamkela ukwanda kwevolumu ye-Si kwaye ke ziphuke ngexesha lemijikelezo ephindaphindayo. 8 20 21 Ngomzamo wokujongana nomda wezinto zokugubungela eziqhuba uombane zangaphambili kunye nokufezekisa intsebenzo egqwesileyo yomjikelo kunye namandla egolide aphezulu avolumethric, kwesi sifundo, samkela i-graphene enemigqabathi emininzi ekhule ngokuthe ngqo kumphezulu we-Si njengento yokugubungela. Uhlobo oluhlalutya lwe-graphene lwe-graphene lubonelela ngomsebenzi oyingqayizivele kunye nosebenzayo we-anode ye-Si njengoko i-graphene enemigqabathi emininzi ingakwazi ukwamkela ukwanda kwevolumu ye-Si ngenkqubo yokushelela phakathi kwemigqabathi elandelanayo ngaphandle kwesidingo sokubonelela ngendawo evulekileyo   kwisixhobo esenziweyo. Kwakhona, i-pellet ye-Si NP egqunywe yi-graphene ibonisa i-12.8 S cm−1 kwi-graphene content y-1 wt% ngothungelwano oluqhelekileyo lwe-percolation. Ngale njongo, sijongana nomceli mngeni wokukhulisa i-graphene ngokuthe ngqo kumphezulu we-Si ngaphandle kokwenzeka kwe-Si carbide (SiC) ngokusebenzisa inkqubo ye-chemical vapour deposition (CVD) ebandakanya i-oxidant ekhanyayo. Ukwenziwa kwe-SiC kuyingozi kwiinkqubo ze-anode ze-Si kuba i-SiC iyinto enganyeliyo uombane eneziphene ezimbalwa. Ngaphezu koko, i-SiC ayisebenzi ekuphenduleni kunye nee-ion ze-Li kwaye ke ilithintela ukungena kwe-ion ze-Li kwi-Si phase. Ngoncedo lwenkqubo yokushelela ye-interlayer ye-graphene kunye nokuphuculwa kokuqhuba, i-Si NPs egqunywe yi-graphene ifikelela kumandla egolide avolumethric e-2,500 mAh cm−3 (vegra i-550 mAh cm−3 ye-graphite esetyenziswa rhoqo), ixabiso liphezulu phakathi kwalawoxelelwe kude kube ngoku kwi-LIB anodes ngelixa ibonisa intsebenzo egqwesileyo yokujikeleza kunye nesantya. ngaphambili Iziphumo Ukukhula kwe-graphene enganyeliyo i-SiC kwi-Si Ukukhula okuthe ngqo kwe-graphene esemgangathweni kwi-Si nge-CVD process kube nzima   kuba imeko yokuveliswa kwe-graphene eqhelekileyo ifuna imeko yokunciphisa efunekayo ukususa umlilo wendalo we-oxide we-Si kumphezulu we-Si, kwaye emva koko iqhube impendulo phakathi kwe-Si kunye neziqwenga zekhabhoni ezidiliziweyo ukwenza i-SiC . Umbhekiselo wethu wokuqala wokusebenzisa i-methane (CH4) njengento eqalayo yekhabhoni edityaniswe ne-H2 ngokuqinisekileyo ayikwazanga ukufumana ukukhula kwe-graphene kwi-Si NPs ( ), ngaloo ndlela ikwenza kuphela i-β-SiC ( ). Ukujongana nale nto, sibandakanyile i-carbon dioxide (CO2), i-oxidant ekhanyayo, kwi-CVD process kunye ne-CH4  (iiref.  ,  ). Ukubandakanywa kwe-CO2 kuyavumela ukuba kuthintelwe ukwenziwa kwe-SiC kwaye kunciphise iqondo lobushushu lokukhula xa kuthelekiswa nokukhula kwe-graphene okwaziwayo kumphezulu . Kulingo lwethu, kwi-900 °C, ukukhula kwe-graphene kwakungaphelelanga okanye kungafani ( ), ngelixa ukukhula kwe-graphene kwi-1,100 °C kwavelisa imililo ye-oxide kumphezulu we-Si ebizinyanisileyo kakhulu kwi-diffusion ye-ion ze-Li ( ). Kwiqondo lobushushu eliphakathi kwe-1,000 °C, i-2–10 imigqabathi ye-graphene yenziwa njengoko iboniswe kwimifanekiso ye-electron microscope (TEM) ( ) ibonisa ngokucacileyo isakhiwo esinemigqabathi kunye nomgama wokubambisanayo osondeleyo kwi-3.4 Å ( , i-inset). Ukujonga ngakumbi kubonisa ukuba imigqabathi yodwa ixhunyiwe ngqo kumphezulu wesithuthi se-Si ezicandeni zayo (iintolo ezibomvu kwi  ) kwaye ihamba kunye nomphezulu we-Si. Le migqabathi ye-graphene egcinwe kakuhle ingagcina isakhiwo sayo sokubeka imigqabathi nokuba ngexesha le-lithiation ngokusebenzisa inkqubo yokushelela ( ), ngaloo ndlela ibonelela ngendlela ehlakaniphile yokwamkela ukwanda kwevolumu ye-Si. Ukukhula kwe-graphene kuye kwazanywa kumphezulu we-Si dioxide (SiO2) kusetyenziswa i-CH4 kunye ne-H2 (iiref.  ,  ). Nangona kunjalo, ukukhula kwe-graphene kwezo nkqubo kwakungasebenzi kakhulu okanye akuzange kuthintelwe ukwenziwa kwe-SiC. Ukukhula okungasebenzi kubekwa ityala kwiindawo zokutshala zecatalytic ezingafaniyo kumphezulu we-SiO2. Ngokuchaseneyo, kwinkqubo yethu, ukongezwa kwe-CO2 kwenza iindawo ezininzi zokutshala i-catalytic ngohlobo lwe-SiO  ezineminye imingcipheko. 22 23 Supplementary Fig. 1 Supplementary Fig. 2 24 25 23 Supplementary Fig. 3 Supplementary Fig. 4 Fig. 1a,b Fig. 1b Fig. 1c Fig. 1d 26 27 x   ( ) Umfanekiso we-TEM obonisa ubukhulu obuncinci be-Gr–Si NP. ( ) Umfanekiso we-TEM obonisa ubukhulu obukhulu kwi-Gr–Si NP efanayo ukusuka kwibhokisi emhlophe kwi  . (I-insets) Imigca yemifanekiso ukusuka kwiibhokisi ezimbini ezibomvu zibonisa ukuba umgama wokubambisanayo phakathi kwemigqabathi ye-graphene yi ~3.4 Å, evumelana kakuhle naleyo yemigqabathi ye-graphene eqhelekileyo esekelwe kumandla edonsayo ka-van der Waals. ( ) Umfanekiso we-TEM obonisa ubukhulu obukhulu obubonisa imvelaphi (iintolo ezibomvu) apho imigqabathi ye-graphene nganye ikhula. ( ) Umzobo wesimemulo obonisa inkqubo yokushelela yemigqabathi yokugubungela i-graphene enokubhabha ukwanda kwevolumu ye-Si. a b a c d Ukukhula kwe-graphene okunganyeliyo i-SiC kuqinisekiswe kuzo zombini izihlomelo ezinkulu kunye nezikwizinga elifanayo. Iipriferensi ze-X-ray photoelectron spectroscopy kwingingqi ye-Si 2   kwaye nemidlalwana ye-X-ray diffraction (XRD) ( ) azibonisi naziphi na iiponti ezihambelana ne-SiC kwi-graphene-coated Si (Gr–Si), AC-coated Si (AC–Si) kunye ne-Si ecocekileyo, ngokuchaseneyo nesampuli yolawulo (SiC–Si) eyenziwe ngeendlela ezingena-CO2 kusetyenziswa i-CH4 kunye ne-H2. Ngakolunye uhlangothi, umfanekiso we-TEM wokuskena usebenzisa i-angle yokuhlola emnyama kakhulu ububonise ukuba i-Si NP inesakhiwo senqamu-shell kunye nenqamu eligqamayo kunye nenqamu elimnyama elihambelana nenqamu ye-Si kunye ne-oxide coating ( ). I-Electron energy loss spectroscopy (EELS) yemidlalwana ( ) efunyenwe kwiindawo ezininzi kulo lonke i-NP ayizange ibonise naziphi na iziqhwala  ezibonisa ukwenziwa kwe-SiC, ziqinisekisa ukukhula okunganyeliyo i-SiC kwinkqubo yokukhula yangoku. Kwakhona, i-SiO2 isiqhwala kwi-108 eV zafunyanwa kwiindawo 1 kunye ne-2 ngokuphawulekayo kunezinye iindawo embindini, okubonisa ukuba ubuso be-SiO2 bulungiselela iindawo zokutshala i-graphene. Ubukho obuqhubekayo bemililo ye-SiO2 kuqinisekiswe kwakhona yi-XRD ( ) kunye ne-EELS ( ) uhlalutyo. p Supplementary Fig. 2 Fig. 2b Fig. 2c 28 Supplementary Fig. 2 Fig. 2b,c   ( ) Iipriferensi ze-X-ray photoelectron spectroscopy kwingingqi ye-Si 2  kwi-Gr–Si, i-SiC–Si, i-AC–Si kunye ne-Si ecocekileyo. ( ) Umfanekiso we-TEM wokuskena we-Gr–Si NP. ( ) I-EELS yemidlalwana yeendawo eziboniswe kwi  . a p b c b Uhlalutyo lwe-TEM olusebenzayo Ngoku sijonga ukusetyenziswa kwe-Gr–Si njengento ye-anode kwi-LIBs. I-lithiation ye-Gr–Si NPs (i-1 wt% graphene) yajongwa ngexesha lokwenyani ngexesha lokwanda kwevolumu yayo kusetyenziswa i-  uhlalutyo lwe-TEM , , , . Kwingqiniso yomsebenzi, ezinye ii-Gr–Si particles zabekwa kwi-electrode edityaniswe negolide (Au). Enye, kodwa ihambayo, i-electrode kunye ne-Li/LiO2 ekupheleni kwayo yabekwa ukuba ichukumise ii-Gr–Si NPs ukuze ziqhube i-lithiation ( ). Nje ukuba uqhagamshelwano ne-electrode yesibini lwenziwa, ii-particles zaqala ukudumba ( ). Iinkcukacha ezithe xelelweyo ngale nkqubo zinokubonwa kwi   kunye ne  . Zimbini iintlobo zezakhiwo ezandayo zafunyanwa, oko kukuthi ii-particles ezingena-defects kunye nee-particles ezinemiphene njengoko zikhanyisiwe kwi  . Kwiimeko apho i-graphene igubungela ngokupheleleyo i-particle kwaye ayinazo iziphene ezicacileyo ( ), ububanzi bandiswa yi ~30% (i-220% yokwanda kwevolumu). Ekupheleni kwe-lithiation, umgama wokubambisanayo wemigqabathi ye-graphene yanda ukuya kwi-3.8 Å efana nokufakwe kwi-Li , kwaye uphawu olulungisiweyo lokugubungela i-graphitic lwagcinwa kuyo yonke i-NP ( ), okubonisa inkqubo yokushelela phakathi kwemigqabathi njengoko kuchaziwe kwi  . Kwiimeko apho kukho indawo enemiphene (bona isekheji eluhlaza kwi  ), ngexesha lokudumba, i-particle yangaphakathi iphukeka kwaye iphukeka ngendawo enemiphene ( ). Iinkqubo zokwaphuka ezifunyenweyo akunakwenzeka ukuba zivela kubukhulu be-particle, kuba i-particle egutyiweyo enkulu kune-fractured kwi   ayizange iphuke (bona ii-particles eziboniswe kwi-0 kunye ne-40 s kwi  ). Kwakhona, ukubona kwangoku  ibonisa ukuba ukuba ayigqunywanga, nkqu ii-particles ezincinci ze-Si (<50 nm) zingaphuka ngenxa yenkqubo yokugqama kwe-Li ngaphakathi kwii-particles ezingakha uxinzelelo olukhulu. Ngapha, ubukhulu obubalulekileyo bokophuka kwe-Si particle buxhomekeke kwimeko, kwaye buhambelana nendlela ukwanda kwevolumu okukwazi ngayo ukudluliselwa. Ubukhulu obubalulekileyo bungadlulela kwi-200 nm (ref.  ). in situ 29 30 31 32 Fig. 3a Fig. 3b Supplementary Fig. 5 Supplementary Movies 1–3 Fig. 3b,c Fig. 3d 33 Fig. 3d Fig. 3c Fig. 3a Fig. 3e Fig. 3 Supplementary Fig. 5 34 35   ( ) I-Gr–Si NPs enxunyekwe kumphezulu we-Au wire kunye ne-electrode yesibini ye-Li/LiO2. ( ) I-Gr–Si NPs efanayo emva kwe-lithiation. ( ) Isishwankathelo sesimemulo sama-Gr–Si NPs alithiyekileyo kubo baboneleleyo nabaneziphene ze-graphene encapsulation. ( , ) Izifanekiso ze-TEM ezisondeleyo kwi ( ) isithintelo esingenazo iziphene (esijikelezwe ngomgca obomvu kwi   kunye ne  ) kunye ne ( ) isithintelo esineziphene (esijikelezwe ngomgca oluhlaza kwi   kunye ne  ). I-EELS yemidlalulo kwezi meko zombini ziqinisekisa i-lithiation. Imigca yemifanekiso ukusuka kwiibhokisi ezibomvu kwezi meko zombini ibonisa imigama yokubambisanayo eyongeziweyo ye-ca. 3.8 Å, efana nokufakwa kwi-graphene interlayer space. a b c d e d a b e a b Uhlalutyo lwe-EELS lwengingqi ngexesha le-lithiation luqinisekisa i-lithiation ye-Si kwiimeko zombini ngokusebenzisa i-Li  -edge engabonakaliyo kufuphi ne-55 eV kunye ne-Si  -edge kwi-100 eV ( ; ref.  ). Umgqabathi oboniswe kumphezulu we-graphene kwi   bubuyekezo kwi-Li/Li2O esalwelweyo. Ngokwesiseko, imigqabathi ye-graphene igcina ukudityaniswa ne-Si ngenxa yeengcambu zayo ezibopheleleneyo ngokhemically kumphezulu we-Si, kwaye ngaxeshanye, inkqubo yokushelela ivumela ukugubungela okuneemigqabathi ezininzi ukuba kube lula ukwanda kwevolumu ye-Si. Kwisifundo esahlukileyo se-  TEM kunye ne-Gr–Si LIB electrode, kwaboniswa ukuba inani eliphakathi leemigqabathi ze-graphene ezilinganiswe kwiindawo ezahlukeneyo lehla ukusuka kwi-9.4 ukuya kwi-5.6 imigqabathi ( ) emva kwe-lithiation yokuqala, iqinisekisa kwakhona inkqubo yokushelela yemigqabathi. K L Fig. 3d,e 36 Fig. 3d ex situ Supplementary Fig. 6 Ukugubungela kwe-graphene kunye nenkqubo yokushelela yemigqabathi yenza amandla okubamba anceda ukugcina ingqibelelo ye-Si particle ngexesha lokwanda kwevolumu. Nangona kunjalo, le nkqubo yokubamba ayibonakali ichaphazela i-Li diffusion, njengoko iz

Part of HackerNoon's growing list of open-source research papers, promoting free access to academic material.

Le audio iveliswe ngolwimi lokuqala lwebali!

Ukuphumelela Okukhulu Kwegraphene Kungenza Iibhetri ze-EV Zihlale Ixesha elide kwaye Zigcine Amandla ngaphezu

About Author

IZIMVO

ZIJONGE IIMPAWU

ELI NQAKU LINIKEZELWE KU

Related Stories

Light-Mode

Classic

Newspaper

Minty

Dark-Mode

Neon Noir

Minty

HN StartUps