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A cikin wannan aikin, rGO / nZVI composites an haɗa su a karon farko ta amfani da hanya mai sauƙi da yanayin muhalli ta amfani da Sophora yellowish leaf tsantsa azaman wakili mai ragewa da kuma daidaitawa don biyan ka'idodin sunadarai na "kore", kamar ƙananan ƙwayoyin cuta masu cutarwa. An yi amfani da kayan aiki da yawa don tabbatar da nasarar haɗin haɗin gwiwar, kamar SEM, EDX, XPS, XRD, FTIR, da kuma yuwuwar zeta, waɗanda ke nuna nasarar ƙirƙira ƙira. Ƙarfin cirewar abubuwan da aka haɗa na labari da nZVI mai tsabta a wurare daban-daban na farawa na maganin rigakafi doxycycline an kwatanta shi don bincika tasirin haɗin gwiwa tsakanin rGO da nZVI. A ƙarƙashin yanayin cire 25mg L-1, 25 ° C da 0.05g, ƙimar cirewar adsorptive na nZVI mai tsabta shine 90%, yayin da adadin cirewar doxycycline ta rGO/nZVI composite ya kai 94.6%, yana mai tabbatar da cewa nZVI da rGO . Tsarin tallan ya dace da tsari na biyu na pseudo-na biyu kuma yana da kyakkyawar yarjejeniya tare da samfurin Freundlich tare da matsakaicin ƙarfin adsorption na 31.61 mg g-1 a 25 ° C da pH 7. An tsara tsarin da ya dace don cire DC. Bugu da ƙari, sake yin amfani da kayan aikin rGO/nZVI ya kasance 60% bayan sake sake haɓakawa guda shida a jere.
Karancin ruwa da gurbatar yanayi yanzu sun zama babbar barazana ga dukkan kasashe. A cikin 'yan shekarun nan, gurɓataccen ruwa, musamman gurɓataccen ƙwayoyin cuta, ya ƙaru saboda karuwar samarwa da amfani yayin bala'in COVID-191,2,3. Saboda haka, haɓaka fasahar fasaha mai mahimmanci don kawar da maganin rigakafi a cikin ruwa mai tsabta aiki ne na gaggawa.
Ɗaya daga cikin maganin rigakafi na Semi-synthetic na ƙungiyar tetracycline shine doxycycline (DC) 4,5. An ba da rahoton cewa ragowar DC da ke cikin ruwa na ƙasa da na sama ba za a iya daidaita su ba, kawai 20-50% ne kawai ke daidaitawa kuma sauran an sake su a cikin muhalli, yana haifar da matsalolin muhalli da lafiya.
Bayyanawa ga DC a ƙananan matakan zai iya kashe ƙwayoyin cuta na photosynthesis na ruwa, yana barazanar yaduwar ƙwayoyin cuta, da kuma ƙara juriya na ƙwayoyin cuta, don haka dole ne a cire wannan gurɓataccen abu daga ruwa mai tsabta. Lalacewar yanayi na DC a cikin ruwa wani tsari ne mai saurin gaske. Physico-chemical tafiyar matakai kamar photolysis, biodegradation da adsorption iya kawai ragewa a low yawa da kuma a sosai low rates7,8. Koyaya, mafi kyawun tattalin arziki, mai sauƙi, abokantaka na muhalli, sauƙin sarrafawa da ingantaccen hanyar shine adsorption9,10.
Nano zero valent iron (nZVI) abu ne mai ƙarfi sosai wanda zai iya cire maganin rigakafi da yawa daga ruwa, gami da metronidazole, diazepam, ciprofloxacin, chloramphenicol, da tetracycline. Wannan ikon ya samo asali ne saboda kyawawan kaddarorin da nZVI ke da su, kamar babban aiki, babban yanki, da wuraren ɗaurin waje da yawa11. Duk da haka, nZVI yana da wuyar haɗuwa a cikin kafofin watsa labaru na ruwa saboda dakarun van der Wells da manyan kaddarorin magnetic, wanda ya rage tasirinsa wajen kawar da gurɓataccen abu saboda samuwar nau'in oxide wanda ke hana reactivity na nZVI10,12. Za'a iya rage haɓakar ƙwayoyin nZVI ta hanyar gyaggyara saman su tare da surfactants da polymers ko ta hanyar haɗa su tare da sauran nanomaterials a cikin nau'i na nau'i, wanda ya tabbatar da kasancewa mai dacewa don inganta zaman lafiyar su a cikin yanayi13,14.
Graphene nau'in nau'in carbon nanomaterial ne mai girma biyu wanda ya ƙunshi sp2-hybridized carbon atom wanda aka shirya a cikin lattice ɗin saƙar zuma. Yana da babban yanki mai girma, ƙarfin injiniya mai mahimmanci, kyakkyawan aiki na electrocatalytic, high thermal conductivity, azumi electron motsi, da kuma dace m abu don tallafawa inorganic nanoparticles a kan ta surface. Haɗuwa da nanoparticles na ƙarfe da graphene na iya ƙetare fa'idodin kowane mutum na kowane abu kuma, saboda fifikon halayensa na zahiri da sinadarai, suna ba da mafi kyawun rarraba nanoparticles don ingantaccen maganin ruwa15.
Cire tsire-tsire sune mafi kyawun madadin abubuwan rage cutar sinadarai waɗanda aka saba amfani da su a cikin haɗin rage graphene oxide (rGO) da nZVI saboda suna samuwa, marasa tsada, mataki ɗaya, lafiyayyen muhalli, kuma ana iya amfani da su azaman wakilai masu ragewa. kamar flavonoids da phenolic mahadi suma suna aiki azaman stabilizer. Saboda haka, Atriplex halimus L. leaf tsantsa da aka yi amfani da matsayin gyara da kuma rufe wakili don kira na rGO / nZVI composites a cikin wannan binciken. Halimus Atriplex daga dangin Amaranthaceae shine tsire-tsire na shekara-shekara mai son nitrogen tare da kewayon yanki16.
Bisa ga wallafe-wallafen da ake da su, Atriplex halimus (A. halimus) an fara amfani da shi don yin rGO/nZVI composites a matsayin hanyar haɗakar tattalin arziki da muhalli. Don haka, makasudin wannan aikin ya ƙunshi sassa huɗu: (1) phytosynthesis na rGO/nZVI da na mahaifa nZVI composites ta amfani da A. halimus ruwa leaf tsantsa, (2). ) nazarin tasirin synergistic na rGO da nZVI a cikin adsorption da kuma kawar da kwayoyin halitta na maganin rigakafi na doxycycline a ƙarƙashin nau'o'in amsawa daban-daban, inganta yanayin tsarin talla, (3) bincikar kayan da aka haɗa a cikin daban-daban ci gaba da jiyya bayan tsarin aiki.
Doxycycline hydrochloride (DC, MM = 480.90, sinadaran dabara C22H24N2O · HCl, 98%), iron chloride hexahydrate (FeCl3.6H2O, 97%), graphite foda saya daga Sigma-Aldrich, Amurka. Sodium hydroxide (NaOH, 97%), ethanol (C2H5OH, 99.9%) da hydrochloric acid (HCl, 37%) an saya daga Merck, Amurka. NaCl, KCl, CaCl2, MnCl2 da MgCl2 an siyi su daga Tianjin Comio Chemical Reagent Co., Ltd. Duk reagents na babban tsaftar nazari ne. An yi amfani da ruwa mai tsafta sau biyu don shirya duk mafita na ruwa.
An tattara samfuran wakilai na A. halimus daga mazauninsu na halitta a cikin Kogin Nilu da ƙasashen da ke bakin tekun Bahar Rum na Masar. An tattara kayan shuka daidai da ƙa'idodin ƙasa da na duniya17. Farfesa Manal Fawzi ta gano nau'ikan tsirrai a cewar Boulos18, kuma Sashen Kimiyyar Muhalli na Jami'ar Alexandria ta ba da izinin tattara nau'ikan tsire-tsire da aka yi nazari don dalilai na kimiyya. Ana gudanar da takaddun shaida a Jami'ar Tanta Herbarium (TANE), bauchi nos. 14 122-14 127, herbarium na jama'a wanda ke ba da damar samun kayan ajiya. Bugu da ƙari, don cire ƙura ko datti, yanke ganyen shuka zuwa ƙananan ƙananan, kurkura sau 3 tare da famfo da ruwa mai tsabta, sa'an nan kuma bushe a 50 ° C. An murƙushe shuka, 5 g na foda mai kyau an nutsar da shi a cikin 100 ml na ruwa mai narkewa kuma an motsa shi a 70 ° C na minti 20 don samun tsantsa. An tace abin da aka samu na Bacillus nicotianae ta takarda tace Whatman kuma an adana shi a cikin bututu masu tsabta da bakararre a 4°C don ƙarin amfani.
Kamar yadda aka nuna a cikin Hoto 1, GO an yi shi ne daga graphite foda ta hanyar Hummers da aka gyara. An tarwatsa 10 MG na GO foda a cikin 50 ml na ruwa mai tsabta don 30 min a karkashin sonication, sa'an nan kuma 0.9 g na FeCl3 da 2.9 g na NaAc an hade don 60 min. 20 ml na atriplex leaf tsantsa an ƙara a cikin bayani mai motsawa tare da motsawa kuma a bar shi a 80 ° C na 8 hours. Sakamakon dakatarwar baƙar fata an tace. An wanke nanocomposites da aka shirya tare da ethanol da ruwa mai bidistilled sannan a bushe a cikin tanda a 50 ° C na 12 hours.
Hotunan tsari da na dijital na haɗin kore na rGO/nZVI da nZVI complexes da kuma cire maganin rigakafi na DC daga gurɓataccen ruwa ta amfani da tsantsa Atriplex halimus.
A taƙaice, kamar yadda aka nuna a cikin siffa 1, 10 ml na maganin chloride baƙin ƙarfe mai ɗauke da 0.05 M Fe3+ ions an ƙara dropwise zuwa 20 ml na maganin tsantsa leaf mai ɗaci na minti 60 tare da matsakaicin dumama da motsawa, sa'an nan kuma an sanya maganin a tsakiya. 14,000 rpm (Hermle, 15,000 rpm) na 15 min don ba da barbashi baƙar fata, wanda aka wanke sau 3 tare da ethanol da ruwa mai tsabta sannan a bushe a cikin tanda mai zafi a 60 ° C. na dare.
Abubuwan da aka haɗar rGO/nZVI da nZVI da aka haɗa su an haɗa su ta UV-bayyana spectroscopy (T70/T80 jerin UV/Vis spectrophotometers, PG Instruments Ltd, UK) a cikin kewayon dubawa na 200-800 nm. Don nazarin yanayin hoto da girman rarraba rGO / nZVI da nZVI composites, an yi amfani da TEM spectroscopy (JOEL, JEM-2100F, Japan, haɓaka ƙarfin lantarki 200 kV). Don kimanta ƙungiyoyi masu aiki waɗanda za su iya shiga cikin tsararren tsire-tsire da ke da alhakin dawo da tsari da daidaitawa, an gudanar da spectroscopy na FT-IR (JASCO spectrometer a cikin kewayon 4000-600 cm-1). Bugu da ƙari, an yi amfani da na'urar nazari mai yuwuwar zeta (Zetasizer Nano ZS Malvern) don nazarin cajin saman nanomaterials da aka haɗa. Don ma'aunin rarrabuwar X-ray na nanomaterials foda, an yi amfani da diffractometer X-ray (X'PERT PRO, Netherlands), yana aiki a halin yanzu (40 mA), ƙarfin lantarki (45 kV) a cikin kewayon 2θ daga 20 ° zuwa 80 ° da CuKa1 radiation (\ (\lambda = \ ) 1.54056 Ao). Na'urar watsawa ta X-ray spectrometer (EDX) (samfurin JEOL JSM-IT100) shine ke da alhakin yin nazarin abun da ke ciki yayin tattara haskoki na Al K-a monochromatic X-ray daga -10 zuwa 1350 eV akan XPS, girman tabo 400 μm K-ALPHA (Thermo Fisher Scientific, Amurka) ƙarfin watsawa na cikakken bakan shine 200 eV kuma kunkuntar bakan shine 50 eV. Ana danna samfurin foda a kan ma'auni, wanda aka sanya shi a cikin ɗakin da ba a so. An yi amfani da bakan C 1 a matsayin tunani a 284.58 eV don ƙayyade ƙarfin ɗauri.
An gudanar da gwaje-gwajen adsorption don gwada tasirin rGO / nZVI nanocomposites da aka haɗa a cikin cire doxycycline (DC) daga mafita mai ruwa. An gudanar da gwaje-gwajen adsorption a cikin 25 ml Erlenmeyer flasks a gudun girgizawa na 200 rpm a kan shaker orbital (Stuart, Orbital Shaker / SSL1) a 298 K. Ta hanyar diluting da DC stock bayani (1000 ppm) tare da bidistilled ruwa. Don tantance tasirin ƙwayar rGO / nSVI akan ƙimar talla, nanocomposites na ma'auni daban-daban (0.01-0.07 g) an ƙara su zuwa 20 ml na bayani na DC. Don nazarin kinetics da adsorption isotherms, 0.05 g na adsorbent an nutsar da shi a cikin wani bayani mai ruwa na CD tare da ƙaddamarwa na farko (25-100 mg L-1). An yi nazarin tasirin pH akan cirewar DC a pH (3-11) da ƙaddamarwar farko na 50 MG L-1 a 25 ° C. Daidaita pH na tsarin ta ƙara ƙaramin adadin HCl ko NaOH bayani (Mitar pH Crison, pH mita, pH 25). Bugu da ƙari, an bincika tasirin yanayin zafin jiki akan gwaje-gwajen adsorption a cikin kewayon 25-55 ° C. An yi nazarin tasirin ƙarfin ionic akan tsarin adsorption ta hanyar ƙara nau'i daban-daban na NaCl (0.01-4 mol L-1) a farkon maida hankali na DC na 50 MG L-1, pH 3 da 7), 25 ° C, da kuma wani nau'in adsorbent na 0.05 g. An auna tallan da ba adsorbed DC ta amfani da dual biam UV-Vis spectrophotometer (T70/T80 jerin, PG Instruments Ltd, UK) sanye take da 1.0 cm tsawon ma'adini cuvettes hanya a matsakaicin raƙuman ruwa (λmax) na 270 da 350 nm. Kashi kashi cire maganin rigakafi na DC (R%; Eq. 1) da adadin adsorption na DC, qt, Eq. 2 (mg/g) an auna ta amfani da ma'auni mai zuwa.
inda% R shine ƙarfin cirewar DC (%), Co shine farkon maida hankali na DC a lokaci 0, kuma C shine maida hankali na DC a lokaci t, bi da bi (mg L-1).
inda qe shine adadin DC adsorbed a kowace naúrar adadin adsorbent (mg g-1), Co da Ce sune ma'auni a lokacin sifili kuma a ma'auni, bi da bi (mg l-1), V shine ƙarar bayani (l) , kuma m shine reagent taro na adsorption (g).
Hotunan SEM (Figs. 2A-C) suna nuna alamar lamellar rGO/nZVI hade tare da nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'i-nau'i) ya tarwatsa a samansa, yana nuna nasarar haɗin nZVI NPs zuwa saman rGO. Bugu da kari, akwai wasu wrinkles a cikin ganyen rGO, suna tabbatar da kawar da ƙungiyoyi masu ɗauke da iskar oxygen lokaci guda tare da maido da A. halimus GO. Waɗannan manyan wrinkles suna aiki azaman rukunin yanar gizo don ɗaukar nauyin baƙin ƙarfe NPs. Hotunan nZVI (Fig. 2D-F) sun nuna cewa NPs na ƙarfe mai siffar zobe sun warwatse sosai kuma ba su haɗu ba, wanda ya faru ne saboda yanayin suturar abubuwan da aka samo asali na tsire-tsire na tsire-tsire. Girman barbashi ya bambanta tsakanin 15-26 nm. Duk da haka, wasu yankuna suna da ilimin halittar jiki mai mahimmanci tare da tsarin bulges da cavities, wanda zai iya samar da babban tasiri mai tasiri na nZVI, tun da za su iya ƙara yiwuwar tarko kwayoyin DC a saman nZVI. Lokacin da aka yi amfani da tsattsauran ra'ayi na Rosa Damascus don haɗakar nZVI, NPs da aka samu sun kasance marasa daidaituwa, tare da ɓarna da siffofi daban-daban, wanda ya rage tasirin su a cikin Cr (VI) adsorption kuma ya karu lokacin amsawa 23. Sakamakon ya yi daidai da nZVI da aka haɗa daga itacen oak da ganyen Mulberry, waɗanda galibinsu nanoparticles ne masu siffar zobe tare da nau'ikan nanometer daban-daban ba tare da ƙaranci ba.
Hotunan SEM na rGO/nZVI (AC), nZVI (D, E) composites da EDX alamu na nZVI/rGO (G) da nZVI (H).
An yi nazarin abubuwan da aka tsara na rGO/nZVI da nZVI da aka haɗa ta hanyar amfani da EDX (Fig. 2G, H). Bincike ya nuna cewa nZVI yana kunshe da carbon (38.29% by mass), oxygen (47.41% by mass) da kuma baƙin ƙarfe (11.84% by mass), amma wasu abubuwa irin su phosphorus24 kuma suna samuwa, wanda za'a iya samuwa daga tsire-tsire. Bugu da ƙari, yawan adadin carbon da oxygen shine saboda kasancewar phytochemicals daga tsire-tsire masu tsire-tsire a cikin samfurori na nZVI na ƙasa. Ana rarraba waɗannan abubuwa daidai gwargwado akan rGO amma a cikin ma'auni daban-daban: C (39.16 wt %), O (46.98 wt%) da Fe (10.99 wt %), EDX rGO/nZVI kuma yana nuna kasancewar wasu abubuwa kamar S, wanda za a iya hade da tsire-tsire masu tsire-tsire, ana amfani da su. Halin C: O na yanzu da abun ciki na baƙin ƙarfe a cikin rGO / nZVI composite ta amfani da A. halimus yana da kyau fiye da yin amfani da tsantsa leaf eucalyptus, kamar yadda ya kwatanta abun da ke ciki na C (23.44 wt.%), O (68.29 wt.%). da Fe (8.27 wt.%). wt %) 25. Nataša et al., 2022 sun ruwaito irin nau'in nau'i na nZVI da aka haɗa daga itacen oak da ganyen Mulberry kuma sun tabbatar da cewa ƙungiyoyin polyphenol da sauran kwayoyin da ke cikin ƙwayar ganye suna da alhakin tsarin ragewa.
Halin ilimin halittar jiki na nZVI da aka haɗa a cikin tsire-tsire (Fig. S2A, B) ya kasance mai siffar siffar siffar siffar siffar siffar siffar siffar siffar siffar siffar siffar siffar siffar siffar siffar siffar siffar siffar siffar siffar siffar siffar siffar siffar siffar siffar siffar siffar siffar siffar siffar siffar siffar siffar siffar siffar siffar da girman girman 23.09 ± 3.54 nm. Wannan mafi rinjayen granular da siffar barbashi yana cikin kyakkyawar yarjejeniya tare da sakamakon SEM. Abdelfatah et al ya sami irin wannan kallo. a cikin 2021 lokacin da aka yi amfani da tsantsa leaf leaf castor a cikin haɗin nZVI11. Ruelas tuberosa leaf tsantsa NPs da aka yi amfani da su azaman wakili mai ragewa a cikin nZVI kuma suna da siffa mai siffar zobe tare da diamita na 20 zuwa 40 nm26.
Hybrid rGO / nZVI hade da hotuna na TEM (Fig. S2C-D) ya nuna cewa rGO wani jirgin sama ne na basal tare da ɓangarorin gefe da wrinkles suna samar da wuraren saukewa da yawa don nZVI NPs; wannan lamellar morphology kuma yana tabbatar da nasarar ƙirƙira na rGO. Bugu da kari, nZVI NPs suna da siffar mai siffar zobe tare da girman barbashi daga 5.32 zuwa 27 nm kuma an saka su a cikin rGO Layer tare da watsawa kusan iri ɗaya. An yi amfani da tsantsa leaf Eucalyptus don haɗa Fe NPs/rGO; Sakamakon TEM ya kuma tabbatar da cewa wrinkles a cikin rGO Layer sun inganta tarwatsawar Fe NPs fiye da Fe NPs masu tsabta kuma sun kara yawan aiki na abubuwan da aka haɗa. An samu irin wannan sakamako ta Bagheri et al. 28 lokacin da aka ƙirƙira abubuwan da aka haɗa ta amfani da fasahar ultrasonic tare da matsakaicin girman nanoparticle na ƙarfe na kusan 17.70 nm.
Ana nuna sifofin FTIR na A. halimus, nZVI, GO, rGO, da rGO/nZVI a cikin figs. 3A. Kasancewar ƙungiyoyi masu aiki na saman a cikin ganyen A. halimus ya bayyana a 3336 cm-1, wanda ya dace da polyphenols, da 1244 cm-1, wanda ya dace da ƙungiyoyin carbonyl da furotin ke samarwa. Sauran kungiyoyi irin su alkanes a 2918 cm-1, alkenes a 1647 cm-1 da kuma CO-O-CO kari a 1030 cm-1 an kuma lura da su, suna nuna kasancewar kayan aikin shuka wanda ke aiki a matsayin masu rufewa kuma suna da alhakin farfadowa. daga Fe2+ zuwa Fe0 kuma tafi zuwa rGO29. Gabaɗaya, sifofin nZVI suna nuna kololuwar shaye-shaye iri ɗaya kamar sukari masu ɗaci, amma tare da ɗan ƙaramin matsayi. Ƙaƙƙarfan band ya bayyana a 3244 cm-1 hade da OH mikewa vibrations (phenols), kololuwa a 1615 yayi daidai da C = C, da kuma makada a 1546 da 1011 cm-1 tasowa saboda mikewa na C = O (polyphenols da flavonoids) , CN - ƙungiyoyin amines aromatic da amines aliphatic an kuma lura da su a 1310 cm-1 da 1190 cm-1, bi da bi13. Bakan FTIR na GO yana nuna kasancewar yawancin ƙungiyoyi masu ɗauke da iskar oxygen, ciki har da alkoxy (CO) mai shimfiɗa band a 1041 cm-1, epoxy (CO) mai shimfiɗa band a 1291 cm-1, C = O shimfiɗa. wani band na C = C mikewa vibrations a 1619 cm-1, band a 1708 cm-1 da kuma wani m band na OH kungiyar mikewa vibrations a 3384 cm-1 bayyana, wanda aka tabbatar da inganta Hummers Hanyar, wanda ya samu nasarar oxidizes da graphite tsari. Lokacin kwatanta rGO da rGO/nZVI hadawa tare da GO spectra, ƙarfin wasu ƙungiyoyi masu dauke da iskar oxygen, irin su OH a 3270 cm-1, sun ragu sosai, yayin da wasu, kamar C = O a 1729 cm-1, sun kasance gaba daya. rage. bace, yana nuna nasarar kawar da ƙungiyoyin aiki masu ɗauke da iskar oxygen a cikin GO ta hanyar cirewar A. halimus. An lura da sabbin halayen halayen rGO a C=C tashin hankali a kusa da 1560 da 1405 cm-1, wanda ke tabbatar da raguwar GO zuwa rGO. An lura da bambance-bambance daga 1043 zuwa 1015 cm-1 kuma daga 982 zuwa 918 cm-1, mai yiwuwa saboda hada kayan shuka31,32. Weng et al., 2018 kuma ya lura da wani gagarumin attenuation na oxygenated kungiyoyin ayyuka a cikin GO, yana tabbatar da nasarar samuwar rGO ta hanyar bioreduction, tun da eucalyptus leaf tsantsa, wanda aka yi amfani da su hada da rage baƙin ƙarfe graphene oxide composites, ya nuna kusa FTIR bakan na shuka bangaren. ƙungiyoyin aiki. 33 .
A. FTIR bakan gallium, nZVI, rGO, GO, hada rGO/nZVI (A). Roentgenogrammy hada rGO, GO, nZVI da rGO/nZVI (B).
Samuwar rGO/nZVI da nZVI composites an tabbatar da su da yawa ta hanyar rarrabuwar X-ray (Fig. 3B). An lura da ƙimar Fe0 mai girma a 2Ɵ 44.5 °, daidai da index (110) (JCPDS no. 06-0696)11. Wani kololuwa a 35.1 ° na jirgin (311) an danganta shi da magnetite Fe3O4, 63.2 ° na iya haɗawa da alamar Miller na jirgin (440) saboda kasancewar ϒ-FeOOH (JCPDS no. 17-0536) 34. Tsarin X-ray na GO yana nuna ƙaƙƙarfan kololuwa a 2Ɵ 10.3° da wani kololuwa a 21.1°, yana nuna cikakkiyar ɓarkewar graphite kuma yana nuna kasancewar ƙungiyoyi masu ɗauke da iskar oxygen a saman GO35. Haɗaɗɗen tsarin rGO da rGO/nZVI sun rubuta bacewar halayen GO da kuma samuwar manyan kololuwar rGO a 2Ɵ 22.17 da 24.7 ° don abubuwan rGO da rGO/nZVI, bi da bi, wanda ya tabbatar da nasarar dawo da GO ta hanyar tsiro. Koyaya, a cikin tsarin rGO/nZVI mai haɗawa, ƙarin kololuwar da ke hade da jirgin saman lattice na Fe0 (110) da bcc Fe0 (200) an lura da su a 44.9 \ (^\circ \) da 65.22 \ (^\circ \), bi da bi. .
Ƙarfin zeta shine yuwuwar tsakanin Layer ionic da aka haɗe zuwa saman ɓangarorin da kuma maganin ruwa wanda ke ƙayyade kaddarorin electrostatic na abu kuma yana auna kwanciyar hankali37. Zata yuwuwar bincike na kayan aikin nZVI, GO, da rGO / nZVI da aka haɗa su sun nuna kwanciyar hankali saboda kasancewar caji mara kyau na -20.8, -22, da -27.4 mV, bi da bi, a saman su, kamar yadda aka nuna a Hoto S1A- C. . Irin waɗannan sakamakon sun yi daidai da rahotanni da yawa waɗanda ke ambaton cewa mafita da ke ɗauke da barbashi tare da yuwuwar ƙimar zeta ƙasa da -25 mV gabaɗaya suna nuna babban matakin kwanciyar hankali saboda ƙin electrostatic tsakanin waɗannan barbashi. Haɗin rGO da nZVI suna ba da damar haɗakarwa don samun ƙarin caji mara kyau kuma don haka yana da kwanciyar hankali fiye da ko dai GO ko nZVI kadai. Saboda haka, abin da ya faru na electrostatic repulsion zai haifar da samuwar barga rGO / nZVI39 composites. Ƙarƙashin ƙwayar GO yana ba da damar tarwatsawa a ko'ina a cikin matsakaici mai ruwa ba tare da haɓaka ba, wanda ke haifar da yanayi mai kyau don hulɗa tare da nZVI. Ana iya danganta cajin mara kyau tare da kasancewar ƙungiyoyin aiki daban-daban a cikin tsantsar kankana mai ɗaci, wanda kuma ya tabbatar da hulɗar tsakanin GO da precursors na ƙarfe da kuma cirewar shuka don samar da rGO da nZVI, bi da bi, da hadaddun rGO / nZVI. Wadannan mahadi na shuka kuma na iya yin aiki azaman masu ɗaukar hoto, yayin da suke hana haɗuwar nanoparticles da ke haifar da haka kuma suna haɓaka kwanciyar hankali40.
Ƙididdigar farko da jihohin valence na nZVI da rGO/nZVI composites an ƙaddara ta XPS (Fig. 4). Nazarin XPS gabaɗaya ya nuna cewa rGO/nZVI haɗaɗɗen galibi sun ƙunshi abubuwan C, O, da Fe, daidai da taswirar EDS (Fig. 4F-H). Bakan C1s ya ƙunshi kololuwa uku a 284.59 eV, 286.21 eV da 288.21 eV wakiltar CC, CO da C = O, bi da bi. An raba bakan O1s zuwa kololuwa uku, gami da 531.17 eV, 532.97 eV, da 535.45 eV, waɗanda aka sanya wa ƙungiyoyin O=CO, CO, da NO, bi da bi. Koyaya, kololuwa a 710.43, 714.57 da 724.79 eV suna nufin Fe 2p3/2, Fe+3 da Fe p1/2, bi da bi. Halin XPS na nZVI (Fig. 4C-E) ya nuna kololuwa ga abubuwan C, O, da Fe. Kololuwa a 284.77, 286.25, da 287.62 eV sun tabbatar da kasancewar ƙarfe-carbon gami, kamar yadda suke nuni ga CC, C-OH, da CO, bi da bi. Bakan O1s yayi daidai da kololuwa uku C-O/iron carbonate (531.19 eV), hydroxyl radical (532.4 eV) da O-C = O (533.47 eV). Mafi girma a 719.6 ana danganta shi zuwa Fe0, yayin da FeOOH ya nuna kololuwa a 717.3 da 723.7 eV, ƙari, mafi girma a 725.8 eV yana nuna kasancewar Fe2O342.43.
Nazarin XPS na nZVI da rGO/nZVI composites (A, B). Cikakken bakan nZVI C1s (C), Fe2p (D), da O1s (E) da rGO/nZVI C1s (F), Fe2p (G), O1s (H) hade.
N2 adsorption / desorption isotherm (Fig. 5A, B) ya nuna cewa nZVI da rGO / nZVI composites suna cikin nau'in II. Bugu da ƙari, takamaiman yanki (SBET) na nZVI ya karu daga 47.4549 zuwa 152.52 m2 / g bayan makanta tare da rGO. Ana iya bayyana wannan sakamakon ta hanyar raguwa a cikin abubuwan magnetic na nZVI bayan makanta rGO, ta haka ne rage haɓakar ƙwayoyin cuta da haɓaka sararin samaniya na abubuwan haɗin gwiwa. Bugu da ƙari, kamar yadda aka nuna a cikin Fig. 5C, ƙarar pore (8.94 nm) na rGO / nZVI composite ya fi na asali nZVI (2.873 nm). Wannan sakamakon yana cikin yarjejeniya da El-Monaem et al. 45 .
Don kimanta ƙarfin haɓakawa don cire DC tsakanin rGO / nZVI composites da asali nZVI dangane da karuwa a cikin ƙaddamarwa na farko, an kwatanta kwatanta ta ƙara yawan adadin kowane adsorbent (0.05 g) zuwa DC a daban-daban na farko. Maganin bincike [25]. -100 MG l-1] a 25 ° C. Sakamakon ya nuna cewa haɓakar cirewa (94.6%) na haɗin rGO / nZVI ya fi na ainihin nZVI (90%) a ƙananan ƙananan (25 mg L-1). Koyaya, lokacin da aka haɓaka maida hankali zuwa 100 MG L-1, haɓakar cirewar rGO/nZVI da nZVI na iyaye sun ragu zuwa 70% da 65%, bi da bi (Hoto 6A), wanda zai iya zama saboda ƙarancin wuraren aiki da lalatawar nZVI abubuwa. Akasin haka, rGO / nZVI ya nuna mafi girman inganci na cirewar DC, wanda zai iya kasancewa saboda tasirin haɗin gwiwa tsakanin rGO da nZVI, wanda wuraren da ke aiki masu ƙarfi don tallatawa sun fi girma, kuma a cikin yanayin rGO / nZVI, ƙari. DC za a iya adsorbed fiye da m nZVI. Bugu da kari, a cikin fig. 6B yana nuna cewa ƙarfin adsorption na rGO / nZVI da nZVI composites sun karu daga 9.4 mg / g zuwa 30 mg / g da 9 mg / g, bi da bi, tare da karuwa a cikin ƙaddamarwa na farko daga 25-100 mg / L. -1.1 zuwa 28.73 mg g-1. Sabili da haka, ƙimar cirewar DC ta kasance da alaƙa mara kyau tare da ƙaddamarwar DC ta farko, wanda ya kasance saboda ƙarancin adadin cibiyoyin amsawa wanda kowane mai talla ya goyi bayan tallan da cire DC a cikin bayani. Don haka, ana iya kammalawa daga waɗannan sakamakon cewa rGO / nZVI composites suna da tasiri mafi girma na adsorption da raguwa, kuma rGO a cikin abun da ke ciki na rGO / nZVI za a iya amfani da su duka a matsayin adsorbent kuma a matsayin kayan aiki.
Ƙarfafawar cirewa da ƙarfin adsorption na DC don rGO / nZVI da nZVI composite sun kasance (A, B) [Co = 25 mg l-1-100 mg l-1, T = 25 ° C, kashi = 0.05 g], pH. akan iyawar adsorption da ingancin cirewar DC akan rGO / nZVI composites (C) [Co = 50 mg L-1, pH = 3-11, T = 25 ° C, kashi = 0.05 g].
Magani pH shine mahimmanci mai mahimmanci a cikin nazarin hanyoyin haɓakawa, tun da yake yana rinjayar matakin ionization, ƙayyadaddun bayanai, da ionization na adsorbent. An gudanar da gwajin a 25 ° C tare da adadin adsorbent akai-akai (0.05 g) da ƙaddamarwar farko na 50 MG L-1 a cikin kewayon pH (3-11). Dangane da bita na wallafe-wallafe46, DC kwayar amphiphilic ce tare da ƙungiyoyin ayyuka masu ionizable da yawa (phenols, ƙungiyoyin amino, alcohols) a matakan pH daban-daban. A sakamakon haka, ayyuka daban-daban na DC da kuma tsarin da ke da alaƙa a kan farfajiyar rGO / nZVI composite na iya yin hulɗar electrostatically kuma suna iya zama kamar cations, zwitterions, da anions, kwayoyin DC sun kasance a matsayin cationic (DCH3 +) a pH <3.3, zwitterionic (DCH20) 3.3 <pH <7.7 da anionic (DCH- ko DC2-) a PH 7.7. A sakamakon haka, ayyuka daban-daban na DC da kuma tsarin da ke da alaƙa a kan farfajiyar rGO / nZVI composite na iya yin hulɗar electrostatically kuma suna iya zama kamar cations, zwitterions, da anions, kwayoyin DC sun kasance a matsayin cationic (DCH3 +) a pH <3.3, zwitterionic (DCH20) 3.3 <pH <7.7 da anionic (DCH- ko DC2-) a PH 7.7. В реannaульые разли Сте и свя Стрнимта Rgo / Nzvi Мпости Вомподейса Мовать Врмовыь электь электь электь электь электь АКы остати и могтавать в Мнитть ввнуовывыратионавв иттиоветьла Н <3,3, цвтттер- ko (DCH20) 3,3 <pH <7,7 da анионный (DCH- ko DC2-) da pH 7,7. A sakamakon haka, ayyuka daban-daban na DC da sifofi masu alaƙa a saman rGO / nZVI composite na iya yin hulɗar lantarki kuma suna iya kasancewa a cikin nau'i na cations, zwitterions, da anions; kwayoyin DC suna kasancewa azaman cation (DCH3+) a pH <3.3; ionic (DCH20) 3.3 <pH <7.7 da anionic (DCH- ko DC2-) a pH 7.7.因此，DC 的各种功能和rGO/nZVI 、两性离子和阴离子的形式存在， DC 分子在pH < 3.3 时以阳离子(DCH3+) 的形式存在，两性离子(DCH20) 3.3 < pH < 7.7 和阴离子(DCH- 或DC2-) 在PH 7.7.因此, DC 的 的种 的 和 和和 可能 材料 的 相关 可能 会 的和, 并并 在 阳离子阳离子 ,, DC 分子分子 在在 阳离子阳离子, DCH3 + +) 形式存在，两性离子(DCH20) 3.3 < pH < 7.7 和阴离子(DCH- 或DC2-) 在PH 7.7. Словательно, различно еские взаиме взтия в ивдвовать ввИдерратионноватионноватионнуатьиатионнуатьиатионнуатьинатионнуатьинатионнать ( рн <3,3. Sabili da haka, ayyuka daban-daban na DC da sifofi masu alaƙa a saman rGO / nZVI composite na iya shiga cikin hulɗar electrostatic kuma sun kasance a cikin nau'i na cations, zwitterions, da anions, yayin da kwayoyin DC sune cationic (DCH3 +) a pH <3.3. Он существует в виде цвитер-иона (DCH20) da 3,3 <pH <7,7 da kuma аниона (DCH- или DC2-) pH 7,7. Ya wanzu azaman zwitterion (DCH20) a 3.3 <pH <7.7 da anion (DCH- ko DC2-) a pH 7.7.Tare da karuwa a pH daga 3 zuwa 7, ƙarfin adsorption da inganci na cirewar DC ya karu daga 11.2 mg / g (56%) zuwa 17 mg / g (85%) (Fig. 6C). Duk da haka, yayin da pH ya karu zuwa 9 da 11, ƙarfin adsorption da ƙwarewar cirewa ya ragu kaɗan, daga 10.6 mg / g (53%) zuwa 6 mg / g (30%), bi da bi. Tare da karuwa a pH daga 3 zuwa 7, DCs sun kasance sun kasance a cikin nau'i na zwitterions, wanda ya sa su kusan ba su da sha'awar lantarki ko ƙin yarda da rGO/nZVI composites, yawanci ta hanyar hulɗar electrostatic. Yayin da pH ya karu a sama da 8.2, an yi cajin saman adsorbent mara kyau, don haka ƙarfin tallan ya ragu kuma ya ragu saboda ƙaddamarwar electrostatic tsakanin doxycycline da aka caji mara kyau da kuma saman adsorbent. Wannan yanayin yana nuna cewa adsorption na DC akan rGO / nZVI composites ya dogara da pH sosai, kuma sakamakon ya nuna cewa rGO / nZVI composites sun dace a matsayin adsorbents a ƙarƙashin yanayin acidic da tsaka tsaki.
An gudanar da tasirin zafin jiki akan adsorption na maganin ruwa na DC a (25-55 ° C). Hoto 7A yana nuna tasirin karuwar zafin jiki akan kawar da tasirin maganin rigakafi na DC akan rGO / nZVI, a bayyane yake cewa ƙarfin cirewa da ƙarfin talla ya karu daga 83.44% da 13.9 mg / g zuwa 47% da 7.83 mg / g. , bi da bi. Wannan gagarumin raguwa na iya kasancewa saboda karuwa a cikin makamashin thermal na DC ions, wanda ke haifar da desorption47.
Tasirin Zazzabi akan Ƙarfin Cirewa da Ƙarfin Adsorption na CD akan rGO/nZVI Composites (A) [Co = 50 mg L-1, pH = 7, Dose = 0.05 g], Adsorbent Dose on Exmoval Efficiency and The Cire Ingarfin CD Tasirin CD Ƙaddamarwa ta farko akan ƙarfin talla da ingancin cirewar DC akan rGO/nSVI composite (B) [Co = 50 mg L-1, pH = 7, T = 25 ° C] (C, D) [Co = 25-100 mg L-1, pH = 7, T = 25 ° C, kashi = 0.05 g.
Tasirin ƙara yawan ƙwayar ƙwayar ƙwayar cuta ta rGO / nZVI daga 0.01 g zuwa 0.07 g akan yadda ake cirewa da kuma iyawar adsorption an nuna a cikin Fig. 7B. Ƙara yawan kashi na adsorbent ya haifar da raguwa a cikin ƙarfin talla daga 33.43 mg / g zuwa 6.74 mg / g. Duk da haka, tare da karuwa a cikin adadin adsorbent daga 0.01 g zuwa 0.07 g, haɓakar cirewa ya karu daga 66.8% zuwa 96%, wanda, saboda haka, ana iya danganta shi da karuwa a yawan cibiyoyin aiki a kan nanocomposite surface.
An yi nazarin tasirin maida hankali na farko akan iyawar adsorption da haɓakar cirewa [25-100 MG L-1, 25 ° C, pH 7, kashi 0.05 g]. Lokacin da aka ƙaddamar da ƙaddamarwa na farko daga 25 MG L-1 zuwa 100 MG L-1, adadin cirewa na rGO / nZVI composite ya ragu daga 94.6% zuwa 65% (Fig. 7C), mai yiwuwa saboda rashin aikin da ake so. shafuka. . Adsorbs babban taro na DC49. A gefe guda, yayin da ƙaddamarwa na farko ya karu, ƙarfin adsorption kuma ya karu daga 9.4 mg / g zuwa 30 mg / g har sai an kai ma'auni (Fig. 7D). Wannan amsawar da ba makawa ta kasance saboda haɓakar ƙarfin tuƙi tare da ƙaddamarwar DC ta farko mafi girma fiye da juriyar juriya na ion na DC don isa saman 50 na rGO/nZVI composite.
Lokacin tuntuɓar juna da nazarin motsa jiki suna nufin fahimtar lokacin ma'auni na adsorption. Na farko, adadin DC da aka tallata a cikin mintuna 40 na farko na lokacin tuntuɓar ya kusan rabin adadin adadin da aka tallata a tsawon lokaci (minti 100). Yayin da kwayoyin DC da ke cikin bayani suna karo da juna yana sa su yin ƙaura da sauri zuwa saman rGO/nZVI composite wanda ke haifar da gagarumin talla. Bayan 40 min, DC adsorption ya karu a hankali kuma a hankali har sai an kai ma'auni bayan 60 min (Fig. 7D). Tun da an bazu adadin da ya dace a cikin mintuna 40 na farko, za a sami ƙarancin karo da kwayoyin DC kuma kaɗan za a sami wuraren aiki don ƙwayoyin da ba a haɗa su ba. Saboda haka, ana iya rage yawan adadin adsorption51.
Don ƙarin fahimtar kinetics na adsorption, an yi amfani da ƙirar layi na pseudo first order (Fig. 8A), pseudo second order (Fig. 8B), da Elovich (Fig. 8C) tsarin motsi. Daga sigogin da aka samu daga nazarin motsa jiki (Table S1), ya bayyana a fili cewa samfurin pseudosecond shine mafi kyawun samfurin don kwatanta kinetics na adsorption, inda aka saita darajar R2 fiye da sauran nau'i biyu. Hakanan akwai kamance tsakanin iyawar adsorption da aka ƙididdige (qe, cal). Oda na biyu-na biyu da ƙimar gwaji (qe, exp.) ƙarin shaida ne cewa oda-na biyu shine mafi kyawun samfuri fiye da sauran samfuran. Kamar yadda aka nuna a cikin Tebu 1, ƙimar α (ƙididdigar ƙaddamarwa na farko) da β (ƙaddamarwa akai-akai) sun tabbatar da cewa adadin tallan ya fi girma fiye da raguwa, yana nuna cewa DC yana kula da adsorb da kyau a kan rGO / nZVI52 composite. .
Shirye-shiryen kinetic na layi na layi na tsari na biyu (A), tsari na farko (B) da Elovich (C) [Co = 25-100 mg l-1, pH = 7, T = 25 ° C, kashi = 0.05 g ].
Nazarin adsorption isotherms yana taimakawa wajen ƙayyade ƙarfin adsorption na adsorbent (RGO / nRVI composite) a wasu nau'o'in adsorbate (DC) da yanayin yanayin tsarin. An ƙididdige madaidaicin ƙarfin adsorption ta amfani da isotherm na Langmuir, wanda ke nuna cewa tallan ya yi kama da juna kuma ya haɗa da samar da nau'in adsorbate monolayer a saman adsorbent ba tare da hulɗar tsakanin su53 ba. Sauran samfuran isotherm guda biyu da ake amfani da su sosai sune samfuran Freundlich da Temkin. Kodayake ba a yi amfani da samfurin Freundlich don ƙididdige ƙarfin talla ba, yana taimakawa wajen fahimtar tsarin ƙaddamarwa daban-daban da kuma cewa guraben da ke kan adsorbent suna da kuzari daban-daban, yayin da samfurin Temkin yana taimakawa wajen fahimtar abubuwan jiki da sinadaran adsorption54.
Figures 9A-C suna nuna makircin layin Langmuir, Freindlich, da Temkin, bi da bi. Ƙimar R2 da aka lissafta daga Freundlich (Fig. 9A) da Langmuir (Fig. 9B) makircin layi da aka gabatar a cikin Table 2 sun nuna cewa adsorption na DC akan rGO / nZVI composite ya bi Freundlich (0.996) da Langmuir (0.988) isotherm. Samfura da Temkin (0.985). Matsakaicin ƙarfin adsorption (qmax), ƙididdiga ta amfani da ƙirar isotherm na Langmuir, shine 31.61 mg g-1. Bugu da kari, ƙididdige ƙimar ma'aunin rabuwa mara ƙima (RL) yana tsakanin 0 da 1 (0.097), yana nuna ingantaccen tsarin talla. In ba haka ba, ƙididdige Freundlich akai-akai (n = 2.756) yana nuna fifiko ga wannan tsarin sha. Bisa ga tsarin layi na Temkin isotherm (Fig. 9C), ƙaddamar da DC a kan rGO / nZVI composite shine tsarin tallan jiki, tun da b shine ˂ 82 kJ mol-1 (0.408) 55. Kodayake adsorption na jiki yawanci ana yin sulhu ta hanyar raunin van der Waals, tallan kai tsaye na yanzu akan abubuwan rGO / nZVI yana buƙatar ƙarancin ƙarfin talla [56, 57].
Freundlich (A), Langmuir (B), da Temkin (C) isotherms adsorption na layi [Co = 25-100 mg L-1, pH = 7, T = 25 °C, kashi = 0.05 g]. Plot na van't Hoff equation for DC adsorption ta rGO/nZVI composites (D) [Co = 25-100 mg l-1, pH = 7, T = 25-55 °C da kashi = 0.05 g].
Don kimanta tasirin canjin zafin jiki akan cirewar DC daga abubuwan rGO / nZVI, sigogin thermodynamic kamar canjin entropy (ΔS), canjin enthalpy (ΔH), da canjin makamashi na kyauta (ΔG) an ƙididdige su daga ma'auni. 3 da 458.
inda \({K}_{e}\)=\(\frac{{C}_{Ae}}{{C}_{e}}\) – thermodynamic ma'auni akai-akai, Ce da CAe - rGO a cikin bayani, bi da bi /nZVI DC maida hankali a kan daidaici. R da RT sune madaidaicin iskar gas da zazzabin adsorption, bi da bi. Ƙididdigar ln Ke da 1 / T yana ba da madaidaiciyar layi (Fig. 9D) daga abin da za a iya ƙayyade ∆S da ∆H.
Ƙimar ΔH mara kyau tana nuna cewa tsarin yana da exothermic. A gefe guda, ƙimar ΔH yana cikin tsarin tallan jiki. Ƙimar ΔG mara kyau a cikin Table 3 suna nuna cewa tallan yana yiwuwa kuma ba tare da bata lokaci ba. Ƙididdiga marasa kyau na ΔS suna nuna babban oda na kwayoyin adsorbent a cikin ruwa (Table 3).
Teburin 4 yana kwatanta haɗin rGO / nZVI tare da wasu adsorbents da aka ruwaito a cikin binciken da suka gabata. A bayyane yake cewa haɗin gwiwar VGO/nCVI yana da babban ƙarfin talla kuma yana iya zama abu mai ban sha'awa don kawar da maganin rigakafi na DC daga ruwa. Bugu da ƙari, ƙaddamar da abubuwan haɗin rGO / nZVI tsari ne mai sauri tare da lokacin daidaitawa na 60 min. Ana iya bayyana kyawawan kaddarorin talla na rGO / nZVI ta hanyar tasirin haɗin gwiwar rGO da nZVI.
Figures 10A, B suna kwatanta tsarin ma'ana don kawar da maganin rigakafi na DC ta hanyar rGO/nZVI da nZVI. Bisa ga sakamakon gwaje-gwajen da aka yi a kan tasirin pH akan ingancin DC adsorption, tare da karuwa a pH daga 3 zuwa 7, DC adsorption a kan rGO / nZVI composite ba a sarrafa shi ta hanyar hulɗar electrostatic, tun lokacin da ya yi aiki a matsayin zwitterion; sabili da haka, canji a cikin ƙimar pH bai shafi tsarin talla ba. Bayan haka, ana iya sarrafa tsarin tallan ta hanyar hulɗar da ba ta da wutar lantarki kamar haɗin gwiwar hydrogen, tasirin hydrophobic, da π-π stacking hulɗar tsakanin rGO/nZVI composite da DC66. Sanannen abu ne cewa tsarin adsorbates na kamshi a saman shimfidar graphene an bayyana shi ta hanyar π–π stacking hulɗar a matsayin babban ƙarfin motsa jiki. Abun da aka haɗe shi ne kayan da aka shimfiɗa mai kama da graphene tare da matsakaicin ɗaukar nauyi a 233 nm saboda canjin π-π *. Dangane da kasancewar zoben kamshi huɗu a cikin tsarin kwayoyin halitta na DC adsorbate, mun yi hasashe cewa akwai tsarin hulɗar π-π-stacking tsakanin mai ƙanshin DC (π-electron acceptor) da yankin mai arziki a π-electrons akan. Farashin RGO. /nZVI composites. Bugu da kari, kamar yadda aka nuna a fig. 10B, an yi nazarin FTIR don nazarin hulɗar kwayoyin halitta na rGO / nZVI composites tare da DC, da kuma FTIR spectra na rGO / nZVI composites bayan DC adsorption an nuna a cikin Hoto 10B. 10 b. An lura da sabon tsayi a 2111 cm-1, wanda ya dace da tsarin rawar jiki na C = C bond, wanda ke nuna kasancewar ƙungiyoyi masu aiki na kwayoyin halitta a saman 67 rGO / nZVI. Sauran kololuwa suna canzawa daga 1561 zuwa 1548 cm-1 kuma daga 1399 zuwa 1360 cm-1, wanda kuma ya tabbatar da cewa hulɗar π-π tana taka muhimmiyar rawa wajen tallata graphene da gurɓataccen yanayi68,69. Bayan adsorption na DC, ƙarfin wasu ƙungiyoyi masu ɗauke da iskar oxygen, irin su OH, ya ragu zuwa 3270 cm-1, wanda ke nuna cewa haɗin gwiwar hydrogen yana ɗaya daga cikin hanyoyin talla. Don haka, dangane da sakamakon, adsorption na DC akan rGO/nZVI composite yana faruwa ne musamman saboda π-π stacking interactions da H-bonds.
Tsarin ma'ana na adsorption na maganin rigakafi na DC ta rGO/nZVI da nZVI complexes (A). FTIR adsorption spectra na DC akan rGO/nZVI da nZVI (B).
Ƙarfin ƙwaƙwalwar ƙwaƙwalwar ƙwaƙwalwar ƙwaƙwalwa na nZVI a 3244, 1615, 1546, da 1011 cm-1 ya karu bayan adsorption na DC akan nZVI (Fig. 10B) idan aka kwatanta da nZVI, wanda ya kamata ya kasance da alaka da hulɗar tare da yiwuwar ƙungiyoyin aiki na carboxylic acid. Ya kungiyoyi a DC. Duk da haka, wannan ƙananan yawan watsawa a cikin duk ƙungiyoyin da aka lura ba su nuna wani canji mai mahimmanci a cikin ingancin adsorption na phytosynthetic adsorbent (nZVI) idan aka kwatanta da nZVI kafin tsarin talla. Dangane da wasu binciken cirewar DC tare da nZVI71, lokacin da nZVI yayi amsa da H2O, ana fitar da electrons sannan kuma ana amfani da H+ don samar da hydrogen mai ƙarfi mai saurin raguwa. A ƙarshe, wasu mahadi na cationic suna karɓar electrons daga hydrogen mai aiki, wanda ya haifar da -C=N da -C=C-, wanda aka danganta ga tsagawar zoben benzene.
Lokacin aikawa: Nov-14-2022