ozi

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A na-achịkwa ihe ndọta nke SrFe12O19 (SFO) hexaferrite siri ike site na mmekọrịta dị mgbagwoju anya nke microstructure ya, nke na-ekpebi mkpa ha na ngwa ndọta na-adịgide adịgide. Họrọ otu SFO nanoparticles nwetara site na sol-gel spontaneous combustion synthesis, ma mee n'ụzọ miri emi structural X-ray powder diffraction (XRPD) characterization site G (L) akara profaịlụ analysis. Nkesa nha kristal enwetara na-ekpughe ndabere doro anya nke nha n'akụkụ ntụzịaka [001] na usoro njikọ, na-eduga n'ichebe kristal flaky. Tụkwasị na nke ahụ, a na-ekpebi nha nke SFO nanoparticles site na nyocha microscopy eletrọnịkị (TEM), na ọnụ ọgụgụ nke kristal dị na ihe ndị ahụ na-eme atụmatụ. A tụlere nsonaazụ ndị a iji gosi nguzobe nke otu ngalaba steeti dị n'okpuru uru dị oke mkpa, yana olu mmeghe sitere na nha ndọta na-adabere na oge, nke ezubere iji kpughee usoro ndọta azụ nke ihe ndọta siri ike.
Ihe ndọta nke Nano nwere nnukwu mkpa sayensị na teknụzụ, n'ihi na ihe ndọta ha na-egosipụta omume dị iche iche nke ukwuu ma e jiri ya tụnyere oke olu ha, nke na-eweta echiche na ngwa ọhụrụ1,2,3,4. N'ime nanostructured ihe, M-ụdị hexaferrite SrFe12O19 (SFO) abụrụla onye na-adọrọ mmasị maka ngwa magnet na-adịgide adịgide5. N'ezie, n'ime afọ ndị na-adịbeghị anya, a na-eme ọtụtụ ọrụ nyocha na ịhazi ihe ndị dabeere na SFO na nanoscale site na nhazi dị iche iche na usoro nhazi iji kwalite nha, morphology, na ihe magnetik6,7,8. Tụkwasị na nke ahụ, ọ natawo nlezianya dị ukwuu na nyocha na mmepe nke usoro njikọta mgbanwe9,10. Nnukwu magnetocrystalline anisotropy dị elu (K = 0.35 MJ / m3) gbakwasara n'akụkụ c-axis nke hexagonal lattice 11,12 bụ nsonaazụ ozugbo nke njikọ dị mgbagwoju anya n'etiti magnetism na nhazi kristal, crystallites na nha ọka, morphology na udidi. Ya mere, ịchịkwa njirimara ndị dị n'elu bụ ihe ndabere maka imezu ihe ndị a chọrọ. Ọgụgụ 1 na-egosi ụdị oghere hexagonal P63 / mmc nke SFO13, yana ụgbọ elu kwekọrọ na nlebara anya nke ọmụmụ nyocha profaịlụ ahịrị.
N'etiti ndị metụtara e ji mara ferromagnetic urughuru size Mbelata, e guzobere otu ngalaba ala n'okpuru oké egwu uru na-eduga na-abawanye na magnetik anisotropy (n'ihi a elu elu ebe ka olu ruru), nke na-eduga na a mmanye field14,15. Mpaghara sara mbara n'okpuru akụkụ dị oke egwu (DC) na ihe ndị siri ike (ụkpụrụ a na-ahụkarị bụ ihe dịka 1 µm), ma kọwaa ya site na nke a na-akpọ coherent size (DCOH)16: nke a na-ezo aka na usoro olu kacha nta maka demagnetization na nha nha nha. (DCOH), Kwuru dị ka olu mmalite (VACT) 14. Otú ọ dị, dị ka egosiri na Figure 2, ọ bụ ezie na nha kristal dị ntakịrị karịa DC, usoro ntụgharị ahụ nwere ike ọ gaghị ekwekọ. Na nanoparticle (NP), olu dị oke egwu nke ngbanwe na-adabere na viscosity magnetik (S), na ndabere ndọta ya na-enye ozi dị mkpa gbasara usoro ngbanwe nke NP magnetization17,18.
N'elu: Eserese eserese nke evolushọn nke ubi mmanye nwere nha urughuru, na-egosi usoro ngbanwe magnetization kwekọrọ (nke sitere na 15). SPS, SD, na MD guzo maka steeti superparamagnetic, otu ngalaba na multidomain, n'otu n'otu; A na-eji DCOH na DC maka dayameta nkwekọ na dayameta dị oke egwu, n'otu n'otu. N'okpuru: Ihe osise nke irighiri ihe dị iche iche, na-egosi uto nke kristal site na otu kristal ruo polycrystalline. na gosi kristal na urughuru nha, n'otu n'otu.
Otú ọ dị, na nanoscale, a na-ewebatakwa akụkụ ọhụrụ mgbagwoju anya, dị ka mmekọrịta magnetik siri ike n'etiti ụmụ irighiri ihe, nkesa nha, ọdịdị ahụ, nsogbu elu, na ntụziaka nke axis dị mfe nke magnetization, nke niile na-eme ka nyocha ahụ sie ike19. 20 . Ihe ndị a na-emetụta nkesa ihe mgbochi ike nke ukwuu ma kwesị ka e lebara ya anya nke ọma, si otú ahụ na-emetụta ọnọdụ ntụgharị magnetization. Na ndabere nke a, ọ dị mkpa karịsịa ịghọta njikọ dị n'etiti ụda magnetik na ụdị nanostructured M-ụdị hexaferrite SrFe12O19. Ya mere, dị ka usoro ihe atụ, anyị na-eji usoro SFO nke a kwadebere site na usoro sol-gel nke ala, na-eme nchọpụta n'oge na-adịbeghị anya. Nsonaazụ gara aga na-egosi na nha nke kristal dị na nsonazụ nanometer, ya na ya na ọdịdị nke crystallites, dabere na ọgwụgwọ okpomọkụ a na-eji. Tụkwasị na nke ahụ, kristal nke ihe atụ ndị dị otú ahụ na-adabere na usoro njikọ, na nyocha zuru ezu ka achọrọ iji dokwuo anya mmekọrịta dị n'etiti crystallites na nha nha. Iji kpughee mmekọrịta a, site na nnyefe eletrọnịkị microscopy (TEM) nyocha jikọtara ya na usoro Rietveld na nyocha profaịlụ ahịrị nke nnukwu ọnụọgụ X-ray powder diffraction, kristal microstructure parameters (ie, crystallites and particle size, shape) jiri nlezianya nyochaa ya. . XRPD) ọnọdụ. Nhazi njirimara na-achọ ịchọpụta njirimara anisotropic nke nanocrystallites enwetara na iji gosi na ọ ga-ekwe omume nyocha profaịlụ ahịrị dị ka usoro siri ike maka ịkọwa ọnụ ọgụgụ kachasị elu na-agbasawanye na nanoscale nso nke (ferrite). Achọpụtara na nkesa nha kristal dị arọ G(L) dabere na ntụzịaka kristal. N'ime ọrụ a, anyị na-egosi na usoro mgbakwunye dị mkpa n'ezie iji wepụta oke metụtara nha iji kọwaa nke ọma nhazi na njirimara magnetik nke ụdị ntụ ntụ dị otú ahụ. A mụọkwara usoro nke ntụgharị magnetik iji dokwuo anya mmekọrịta dị n'etiti njirimara nhazi ọdịdị na omume magnetik.
Nyocha Rietveld nke X-ray powder diffraction (XRPD) data na-egosi na nha crystallite tinyere c-axis nwere ike gbanwee site na ọgwụgwọ okpomọkụ kwesịrị ekwesị. Ọ na-egosi kpọmkwem na mmụba kachasị elu a na-ahụ na nlele anyị nwere ike ịbụ n'ihi ọdịdị anisotropic crystallite. Na mgbakwunye, nkwekọ n'etiti nkezi dayameta nke Rietveld nyochara na eserese Williamson-Hall ( na na Tebụl S1) na-egosi na kristal dị ihe fọrọ nke nta ka ọ bụrụ enweghị nsogbu na enweghị nrụrụ nhazi. The evolushọn nke crystallite size nkesa n'akụkụ dị iche iche ntụziaka na-elekwasị anya anyị na nwetara urughuru size. Nyocha adịghị mfe, n'ihi na sample enwetara site sol-gel spontaneous combustion mejupụtara agglomerates nke ahụ nwere porous Ọdịdị6,9, iri abụọ na otu. A na-eji TEM mụọ usoro ime nke ihe nlele ule n'ụzọ zuru ezu karị. A na-akọpụta ihe onyonyo na-egbuke egbuke na eserese 3a-c (maka nkọwa zuru ezu nke nyocha, biko rụtụ aka na ngalaba 2 nke ihe mgbakwunye). Ihe nlele ahụ na-agụnye ihe ndị nwere ọdịdị nke obere iberibe. platelet ndị ahụ na-ejikọta ọnụ iji mepụta mkpokọta porous nke nha na ọdịdị dị iche iche. Iji chọpụta nha nkesa nke platelet, ejiri aka jiri ngwa ImageJ tụọ mpaghara nke irighiri ihe 100 nke nlele ọ bụla. The dayameta nke Ẹkot okirikiri na otu urughuru ebe dị ka uru na-kwuru na nnọchiteanya size nke ọ bụla tụrụ ibe. A na-achịkọta nsonaazụ nke ihe nlele SFOA, SFOB na SFOC na eserese 3d-f, a na-akọkwa ọnụ ahịa dayameta nkezi. Ịbawanye okpomọkụ nhazi na-abawanye nha nke ihe ndị ahụ na obosara nkesa ha. Site na ntụnyere n'etiti VTEM na VXRD (Table 1), enwere ike ịhụ na n'ihe gbasara SFOA na SFOB samples, ọnụ ọgụgụ nke kristal dị n'otu akụkụ na-egosi ọdịdị polycrystalline nke lamellae ndị a. N'ụzọ dị iche, urughuru olu nke SFOC dị ka nkezi kristal olu, na-egosi na ọtụtụ n'ime lamellae bụ otu kristal. Anyị na-arụtụ aka na nha anya nke TEM na X-ray diffraction dị iche, n'ihi na na nke ikpeazụ, anyị na-atụle ngọngọ mgbasa ozi na-ejikọta ọnụ (ọ nwere ike ịbụ obere karịa flake nkịtị): Tụkwasị na nke ahụ, obere ntụgharị njehie nke mgbasa ozi ndị a. a ga-agbakọ ngalaba site na diffraction.
Ihe oyiyi TEM na-egbuke egbuke nke (a) SFOA, (b) SFOB na (c) SFOC na-egosi na ha bụ ihe mejupụtara nke nwere ụdị efere. Egosiri nkesa nha nha nha na histogram nke panel (df).
Dị ka anyị hụkwara na nyocha gara aga, kristal ndị dị na ezigbo ntụ ntụ na-etolite usoro polydispers. Ebe ọ bụ na usoro X-ray na-enwe mmetụta dị ukwuu na ngọngọ mgbasa ozi na-ejikọta ọnụ, a chọrọ nyocha nke ọma nke data diffraction ntụ ntụ iji kọwaa ezigbo nanostructures. N'ebe a, a na-atụle nha nke crystallites site na njirimara nke ọrụ nkesa kristal dị arọ G (L) 23, nke a pụrụ ịkọwa dị ka njupụta nke puru omume nke ịchọta crystallites nke ọdịdị na nha, na ịdị arọ ya bụ nha nhata. ya. Mpịakọta, n'ihe atụ a tụlere. Site n'ụdị kristal prismatic, enwere ike gbakọọ nkezi nha kristal dị arọ (nkezi ogologo akụkụ na ntụzịaka [100], [110] na [001]). Ya mere, anyị na-ahọrọ niile atọ SFO samples dị iche iche urughuru nha n'ụdị anisotropic flakes (lee ntụaka 6) iji nyochaa irè nke usoro a iji nweta ezi crystallite size nkesa nke nano-ọnụ ọgụgụ ihe. Iji nyochaa ntụgharị anisotropic nke kristal ferrite, a na-eme nyocha profaịlụ ahịrị na data XRPD nke ọnụ ọgụgụ ndị ahọpụtara. Ihe nlele SFO a nwalere enweghị nghọta dị mma (dị ọcha) dị elu site na otu ụgbọ elu kristal, yabụ na ọ gaghị ekwe omume ikewapụta onyinye na-agbasawanye ahịrị na nha na mgbagha. N'otu oge ahụ, a na-ahụ anya mgbasawanye nke ahịrị diffraction nwere ike ịbụ n'ihi nha nha, na nkezi kristal na-egosipụta site na nyocha nke ọtụtụ ahịrị. Ọgụgụ 4 na-atụnyere ọrụ nkesa nha kristal dị oke nha G(L) n'akụkụ ntụzịaka crystallographic akọwapụtara. Ụdị ụdị nkesa nha kristal bụ nkesa lognormal. Otu njirimara nke nkesa nha niile enwetara bụ ịdị n'otu. N'ọtụtụ oge, nkesa a nwere ike ịsị na ọ bụ usoro nhazi akụkụ ahụ akọwapụtara. Ọdịiche dị n'etiti nkezi gbakọọ nha nke ọnụ ọgụgụ kacha elu ahọpụtara na uru ewepụtara na ndozi Rietveld dị n'ime oke a na-anabata (na-atụle na usoro nhazi ngwa ọrụ dị iche n'etiti ụzọ ndị a) ma bụrụ otu ihe ahụ site na nhazi ụgbọ elu kwekọrọ. Debye Nkezi nha enwetara kwekọrọ na nha nha Scherrer, dị ka egosiri na Tebụl 2. Usoro nke nha nha nha nha kristal dị elu nke usoro ihe ngosi abụọ dị iche iche yiri nke ahụ, na ntụgharị nke nha zuru oke dị obere. Ọ bụ ezie na enwere ike inwe esemokwu na Rietveld, dịka ọmụmaatụ, n'ihe banyere (110) ntụgharị uche nke SFOB, ọ nwere ike jikọta ya na mkpebi ziri ezi nke ndabere n'akụkụ abụọ nke ntụgharị uche ahọpụtara n'ebe dị anya nke 1 degrees 2θ na nke ọ bụla. uzo. Ka o sina dị, nkwekọrịta magburu onwe ya n'etiti teknụzụ abụọ ahụ na-akwado mkpa nke usoro ahụ. Site na nyocha nke mgbasawanye elu, o doro anya na nha ya na [001] nwere ịdabere kpọmkwem na usoro nhazi ahụ, na-eme ka e guzobe crystallites flaky na SFO6,21 nke sol-gel mebere. Njirimara a na-emeghe ụzọ maka iji usoro a chepụta nanocrystals nwere ụdị mmasị. Dị ka anyị niile maara, mgbagwoju kristal Ọdịdị nke SFO (dị ka e gosiri na Figure 1) bụ isi nke ferromagnetic omume nke SFO12, otú ahụ udi na size àgwà nwere ike gbanwee na-ebuli imewe nke sample maka ngwa (dị ka na-adịgide adịgide). magnetik). Anyị na-arụtụ aka na nyocha nke kristal bụ ụzọ dị ike isi kọwaa anisotropy nke ọdịdị crystallite, ma na-ewusi nsonaazụ enwetara na mbụ.
(a) SFOA, (b) SFOB, (c) SFOC ahọpụtara echiche (100), (110), (004) nkesa nha kristal dị arọ G (L).
Iji nyochaa ịdị irè nke usoro ahụ iji nweta nkesa kristal ziri ezi nke ihe nano-powder ma tinye ya na nanostructures mgbagwoju anya, dị ka e gosiri na 5, anyị ekwenyela na usoro a dị irè na ihe nanocomposite (ụkpụrụ ọnụ ọgụgụ). Ihe mejupụtara izi ezi nke ikpe ahụ bụ SrFe12O19/CoFe2O4 40/60 w/w%). Nsonaazụ ndị a dabara nke ọma na nyocha Rietveld (lee isiokwu nke eserese 5 maka ntụnyere), ma e jiri ya tụnyere usoro nke otu oge, SFO nanocrystals nwere ike ime ka ọdịdị nke efere dị ka morphology pụta ìhè. A na-atụ anya na nsonaazụ ndị a ga-etinye nyocha profaịlụ ahịrị a na sistemu dị mgbagwoju anya nke ọtụtụ usoro kristal dị iche iche nwere ike ịgbakọ na-enweghị atụfu ozi gbasara ihe owuwu ha.
Nkesa nha kristal nke olu dị arọ G (L) nke ntụgharị ahọpụtara nke SFO ((100), (004)) na CFO (111) na nanocomposites; Maka ntụnyere, ụkpụrụ nyocha Rietveld kwekọrọ bụ 70 (7), 45 (6) na 67 (5) nm6.
Dị ka egosiri na eserese 2, mkpebi nke nha nke ngalaba magnetik na nhụta ziri ezi nke ụda anụ ahụ bụ ihe ndabere maka ịkọwa usoro mgbagwoju anya dị otú ahụ na maka nghọta doro anya nke mmekọrịta na usoro nhazi n'etiti ihe ndọta. N'oge na-adịbeghị anya, a mụọla omume magnetik nke ihe atụ SFO n'ụzọ zuru ezu, na-eleba anya n'ụzọ pụrụ iche na usoro ntụgharị nke magnetization, iji mụọ akụkụ a na-apụghị ịgbagha agbagha nke ike ndọta (χirr) (Ọnọdụ S3 bụ ihe atụ nke SFOC)6. Iji nweta nghọta miri emi nke usoro ntụgharị ndọta n'ime nanosystem dabere na ferrite, anyị mere nha ntụrụndụ magnetik na mpaghara azụ (HREV) ka saturation na ntụzịaka enyere. Tụlee \(M\ekpe(t\ aka nri)\proptoSln'ekpe(t'right)\) (lee foto 6 na ihe mgbakwunye maka nkọwa ndị ọzọ) wee nweta olu mmalite (VACT). Ebe enwere ike kọwapụta ya dị ka olu kacha nta nke enwere ike ịtụgharị ọnụ na mmemme, oke a na-anọchi anya olu “magnetic” nke etinyere na usoro ngbanwe. Uru VACT anyị (lee Tebụl S3) dabara na okirikiri nwere dayameta nke ihe dịka 30 nm, nke akọwara dị ka dayameta na-arụkọ ọrụ ọnụ (DCOH), nke na-akọwa oke elu nke ngbanwe magnetization nke sistemu site na ntughari na-agbanwe agbanwe. Ọ bụ ezie na enwere nnukwu ọdịiche dị na ụda anụ ahụ (SFOA bụ ugboro 10 karịa SFOC), ụkpụrụ ndị a na-adịgide adịgide na obere, na-egosi na usoro ntụgharị magnetization nke sistemụ niile ka bụ otu (kwekọrọ na ihe anyị na-ekwu). bụ otu ngalaba ngalaba) 24 . N'ikpeazụ, VACT nwere oke anụ ahụ pere mpe karịa nyocha XRPD na TEM (VXRD na VTEM na tebụl S3). Ya mere, anyị nwere ike ikwubi na usoro ngbanwe ahụ abụghị nanị na-eme site na ntụgharị dị iche iche. Rịba ama na nsonaazụ enwetara site na iji magnetometer dị iche iche (ọgụgụ S4) na-enye ụkpụrụ DCOH yiri ya. N'akụkụ a, ọ dị ezigbo mkpa ịkọwa dayameta dị oke egwu nke otu akụkụ ngalaba (DC) iji chọpụta usoro ngbanwe nke ezi uche dị na ya. Dịka nyocha anyị siri dị (lee ihe mgbakwunye), anyị nwere ike ịpụta na VACT enwetara gụnyere usoro ntụgharị na-adịghị agbanwe agbanwe, n'ihi na DC (~ 0.8 µm) dị anya na DC (~ 0.8 µm) nke ụmụ irighiri anyị, ya bụ, e guzobere mgbidi ngalaba anaghị enweta nkwado siri ike wee nweta otu nhazi ngalaba. Enwere ike ịkọwa nsonaazụ a site na nhazi nke ngalaba mmekọrịta25, 26. Anyị na-eche na otu crystallite na-ekere òkè na ngalaba mmekọrịta, nke na-agbatị na ihe ndị jikọtara ọnụ n'ihi microstructure heterogeneous nke ihe ndị a27,28. Ọ bụ ezie na ụzọ X-ray na-enwe mmetụta naanị maka ọmarịcha microstructure nke ngalaba (microcrystals), nha ntụrụndụ magnetik na-enye ihe akaebe nke ihe mgbagwoju anya nwere ike ime na SFOs nanostructured. Ya mere, site n'ịkwalite nha nanometer nke ọka SFO, ọ ga-ekwe omume igbochi ịgbanwere usoro ntụgharị nke ọtụtụ ngalaba, si otú a na-ejigide nnukwu mmanye nke ihe ndị a.
(a) Ogologo magnetization nke na-adabere na oge nke SFOC tụrụ n'ọnọdụ dị iche iche HREV ụkpụrụ mgbe saturation na-5 T na 300 K (gosiri na-esote data nnwale) (magnetization bụ normalized dị ka arọ nke sample); maka idoanya, Inset na-egosi data nnwale nke ubi 0.65 T (oji ojii), nke nwere ihe kachasị mma (akara uhie) (magnetization bụ normalized na uru mbụ M0 = M (t0)); (b) viscosity magnetik kwekọrọ (S) bụ ntụgharị nke SFOC A ọrụ nke ubi (akara bụ ntuziaka maka anya); (c) atụmatụ usoro ịgbalite nwere nkọwa oke anụ ahụ / ndọta.
N'ikwu okwu n'ozuzu, ngbanwe magnetization nwere ike ime site na usoro nhazi mpaghara, dị ka mgbidi mgbidi ngalaba, mgbasa, na ntu na ịtọpụ. N'ihe banyere irighiri ferrite nke otu ngalaba, usoro ịgbalite bụ nucleation na-ebute ya site na mgbanwe ndọta dị ntakịrị karịa mkpokọta ngbanwe magnetik (dị ka egosiri na eserese 6c)29.
Ọdịiche dị n'etiti magnetism dị oke egwu na dayameta anụ ahụ na-egosi na ọnọdụ na-adịghị ahụkebe bụ ihe omume na-ejikọta ọnụ nke ntụgharị magnetik, nke nwere ike ịbụ n'ihi enweghị ihe na-adịghị mma na elu, nke na-ejikọta ya mgbe oke nha na-abawanye 25, na-ebute mgbanwe site na. edo magnetization steeti.
Ya mere, anyị nwere ike ikwubi na n'ime usoro a, usoro ntụgharị magnetization dị nnọọ mgbagwoju anya, na mgbalị iji belata nha na nha nanometer na-arụ ọrụ dị mkpa na mmekọrịta dị n'etiti microstructure nke ferrite na magnetism. .
Ịghọta mmekọrịta dị mgbagwoju anya n'etiti nhazi, ụdị na magnetism bụ ihe ndabere maka ịmepụta na ịmepụta ngwa n'ọdịnihu. Nyocha profaịlụ ahịrị nke usoro XRPD ahọpụtara nke SrFe12O19 kwadoro ọdịdị anisotropic nke nanocrystals nwetara site na usoro njikọ anyị. Ejikọtara ya na nyocha TEM, a gosipụtara ọdịdị polycrystalline nke ihe a, ma emesịa kwenye na nha nke SFO nyochara na ọrụ a dị ala karịa otu akụkụ dị oke egwu, n'agbanyeghị ihe akaebe nke uto crystallite. Na ndabere nke a, anyị na-atụ aro usoro ndọta na-enweghị mgbagha dabere na nhazi nke ngalaba mmekọrịta nke mejupụtara crystallites jikọtara ọnụ. Nsonaazụ anyị gosipụtara njikọ chiri anya n'etiti morphology urughuru, nhazi kristal na nha kristal dị na ọkwa nanometer. Ọmụmụ ihe a na-achọ ịkọwapụta usoro ndọta ngbanwe nke ihe ndọta siri ike nanostructured na ikpebi ọrụ nke njirimara microstructure na omume ndọta na-esi na ya pụta.
A na-ejikọta ihe atụ ndị ahụ site na iji citric acid dị ka onye na-emepụta ihe / mmanụ ọkụ dị ka usoro nchịkọta ọkụ ọkụ nke sol-gel si dị, nke a na-akọ na Reference 6. A na-eme ka ọnọdụ nhazi ahụ dịkwuo mma iji nweta nha atọ dị iche iche nke ihe nlele (SFOA, SFOB, SFOC), bụ ndị bụ isi. enwetara site na ọgwụgwọ annealing kwesịrị ekwesị na okpomọkụ dị iche iche (1000, 900, na 800 ° C, n'otu n'otu). Tebụlụ S1 na-achịkọta ihe ndọta ma chọpụta na ha yitere. A kwadokwara nanocomposite SrFe12O19/CoFe2O4 40/60 w/w% n'otu aka ahụ.
A tụlere ụkpụrụ nhụsianya ahụ site na iji radieshon CuKα (λ = 1.5418 Å) na Bruker D8 ntụ ntụ diffractometer, na obosara ihe nkedo slit ka edobere ka 0.2 mm. Jiri VANTEC counter nakọta data na 2θ nso nke 10-140°. A na-echekwa okpomọkụ n'oge ndekọ data na 23 ± 1 Celsius. A na-atụle ntụgharị site na teknụzụ nzọụkwụ-na-scan, na nzọụkwụ ogologo nke ihe nlele ule niile bụ 0.013 ° (2theta); Uru kacha elu nke nha nha bụ -2.5 na + 2.5° (2theta). Maka ọnụ ọgụgụ kasị elu nke ọ bụla, a na-agbakọ ngụkọta nke quanta 106, ebe maka ọdụ ahụ nwere ihe dịka 3000 quanta. Ahọpụtara ọtụtụ ọnụ ọgụgụ nnwale (kewapụrụ ma ọ bụ nke kpuchiri ekpuchi) maka nyocha ọzọ n'otu oge: (100), (110) na (004), nke mere na akụkụ Bragg dị nso n'akụkụ Bragg nke akara ndebanye aha SFO. Emeziri ike nnwale ahụ maka ihe kpatara Lorentz polarization, ma wepụrụ ndabere ya site na ngbanwe ahịrị chere. A na-eji ọkọlọtọ NIST LaB6 (NIST 660b) mee ka ngwa ọrụ na mgbasawanye spectral. Jiri LWL (Louer-Weigel-Louboutin) deconvolution method 30,31 nweta dị ọcha diffraction ahịrị. Emebere usoro a na mmemme nyocha profaịlụ PROFIT-software32. Site na ndaba nke data ike tụrụ nke ihe nlele na ọkọlọtọ nwere ọrụ pseudo Voigt, a na-ewepụta ahịrị ahịrị ziri ezi kwekọrọ na contour f(x). A na-ekpebi ọrụ nkesa G (L) site na f(x) site na ịgbaso usoro ewepụtara na ntụaka 23. Maka nkọwa ndị ọzọ, biko rụtụ aka na ihe mgbakwunye. Dịka mgbakwunye na nyocha profaịlụ ahịrị, a na-eji mmemme FULLPROF mee nyocha Rietveld na data XRPD (nkọwa nwere ike ịchọta na Maltoni et al. 6). Na nkenke, na ụdị Rietveld, a na-akọwa ọnụ ọgụgụ dị iche iche site na ọrụ Thompson-Cox-Hastings pseudo Voigt gbanwere. Emere nchacha data LeBail n'ụkpụrụ NIST LaB6 660b iji gosi ntinye aka nke ngwa na mgbasawanye elu. Dị ka FWHM gbakọrọ (obosara zuru oke na ọkara nke oke kacha elu), enwere ike iji akara Debye-Scherrer gbakọọ nha nha nha nha nke ngalaba kristal na-agbasasị ọnụ:
Ebe λ bụ ogologo oge radieshon X-ray, K bụ ihe kpatara ọdịdị ya (0.8-1.2, na-abụkarị 0.9), na θ bụ akụkụ Bragg. Nke a na-emetụta: ntụgharị ahọpụtara, nhazi ụgbọ elu kwekọrọ na ụkpụrụ dum (10-90 °).
Tụkwasị na nke ahụ, a na-eji microscope Philips CM200 na-arụ ọrụ na 200 kV ma kwadebere ya na LaB6 filament maka nyocha TEM iji nweta ozi gbasara morphology na nkesa nha.
A na-eji ngwa abụọ dị iche iche na-eme nha izu ike magnetik: Sistemụ Nleba Ngwongwo anụ ahụ (PPMS) sitere na Quantum Design-Vibrating Sample Magnetometer (VSM), nke nwere 9 T superconducting magnet, na MicroSense Model 10 VSM nwere electromagnet. Ubi ahụ bụ 2 T, ihe nlele ahụ jupụtara n'ọhịa (μ0HMAX: -5 T na 2 T, n'otu n'otu maka ngwá ọrụ ọ bụla), mgbe ahụ, a na-etinye mpaghara ntụgharị (HREV) iji weta ihe nlele ahụ na mpaghara mgbanwe (nso HC). ), wee dekọọ ire ere ndọta dịka ọrụ nke oge karịrị nkeji 60. A na-eme nha ahụ na 300 K. A na-enyocha olu mmalite nke kwekọrọ na ụkpụrụ ndị ahụ akọwapụtara na ihe mgbakwunye.
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