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ʻO ka wikiwiki o ka hoʻomohala ʻana o ka nanotechnology a me kona hoʻohui ʻana i nā noi o kēlā me kēia lā hiki ke hoʻoweliweli i ke kaiapuni. ʻOiai ua hoʻokumu maikaʻi ʻia nā ʻano ʻōmaʻomaʻo no ka hoʻohaʻahaʻa ʻana i nā mea haumia organik, ʻo ka hoʻōla ʻana o nā mea haumia crystalline inorganic he mea hopohopo nui ia ma muli o ko lākou ʻike haʻahaʻa i ka biotransformation a me ka nele o ka hoʻomaopopo ʻana i nā pilina ʻili o nā mea me nā mea olaola. Maanei, hoʻohana mākou i kahi kumu hoʻohālike 2D MXenes inorganic Nb i hui pū ʻia me kahi ʻano loiloi parameter maʻalahi e hahai i ke ʻano bioremediation o nā nanomaterials ceramic 2D e ka microalgae ʻōmaʻomaʻo ʻo Raphidocelis subcapitata. Ua ʻike mākou ua hoʻohaʻahaʻa ka microalgae i nā MXenes Nb ma muli o nā pilina physico-chemical e pili ana i ka ʻili. I ka wā mua, ua hoʻopili ʻia nā nanoflakes MXene papa hoʻokahi a me nā multilayer i ka ʻili o ka microalgae, kahi i hoʻemi iki i ka ulu ʻana o ka algae. Eia naʻe, ma hope o ka launa pū ʻana me ka ʻili, ua hoʻopau ka microalgae i nā nanoflakes MXene a hoʻokaʻawale hou iā lākou i NbO a me Nb2O5. No ka mea, ʻaʻohe ʻawahia o kēia mau oxides i nā cell microalgae, hoʻopau lākou i nā nanoparticles Nb oxide ma o kahi ʻano absorption e hoʻihoʻi hou i ka microalgae ma hope o 72 mau hola o ka mālama ʻana i ka wai. Hōʻike pū ʻia nā hopena o nā meaʻai e pili ana i ka absorption i ka hoʻonui ʻia ʻana o ka nui o ke kelepona, ko lākou ʻano laumania a me ka loli ʻana o ka ulu ʻana. Ma muli o kēia mau ʻike, hoʻoholo mākou ʻo ka manawa pōkole a lōʻihi o nā MXenes e pili ana iā Nb i loko o nā kaiaola wai maʻemaʻe e hiki ke hana i nā hopena liʻiliʻi wale nō o ke kaiapuni. He mea kūpono ia, me ka hoʻohana ʻana i nā nanomaterials ʻelua-dimensional e like me nā ʻōnaehana hoʻohālike, hōʻike mākou i ka hiki ke hahai i ka hoʻololi ʻana o ke ʻano ʻoiai i nā mea i hoʻopili maikaʻi ʻia. Ma keʻano holoʻokoʻa, pane kēia haʻawina i kahi nīnau koʻikoʻi koʻikoʻi e pili ana i nā kaʻina hana e pili ana i ka pilina o luna e hoʻokele ana i ka ʻano bioremediation o nā nanomaterials 2D a hāʻawi i kahi kumu no nā haʻawina pōkole a lōʻihi o ka hopena o ke kaiapuni o nā nanomaterials crystalline inorganic.
Ua nui ka hoihoi i loaʻa mai nā Nanomaterials mai ko lākou ʻike ʻia ʻana, a ua komo koke nā ʻenehana nano like ʻole i kahi pae hoʻomaikaʻi1. ʻO ka mea pōʻino, ʻo ka hoʻohui ʻana o nā nanomaterials i nā noi o kēlā me kēia lā hiki ke alakaʻi i nā hoʻokuʻu ulia pōpilikia ma muli o ka hoʻolei pono ʻole ʻana, ka mālama pono ʻole ʻana, a i ʻole nā ​​​​​​kahua palekana kūpono ʻole. No laila, he mea kūpono ke manaʻo e hiki ke hoʻokuʻu ʻia nā nanomaterials, me nā nanomaterials ʻelua-dimensional (2D), i loko o ke kaiapuni kūlohelohe, ʻaʻole i maopopo piha ke ʻano a me ka hana olaola. No laila, ʻaʻole ia he mea kupanaha ua kālele nā ​​​​hopohopo ecotoxicity i ka hiki o nā nanomaterials 2D ke komo i loko o nā ʻōnaehana wai2,3,4,5,6. I loko o kēia mau kaiaolaola, hiki i kekahi mau nanomaterials 2D ke launa pū me nā meaola like ʻole ma nā pae trophic like ʻole, me ka microalgae.
ʻO nā Microalgae he mau meaola mua i loaʻa maoli i loko o nā kaiaola wai maʻemaʻe a me ke kai e hana ana i nā ʻano huahana kemika like ʻole ma o ka photosynthesis7. No laila, he mea koʻikoʻi lākou i nā kaiaola wai8,9,10,11,12 akā he mau hōʻailona koʻikoʻi hoʻi, ʻaʻole pipiʻi a hoʻohana nui ʻia o ka ecotoxicity13,14. ʻOiai ʻo nā cell microalgae e hoʻonui koke a pane koke i ke alo o nā hui like ʻole, ke hoʻohiki nei lākou no ka hoʻomohala ʻana i nā ʻano hana aloha kaiapuni no ka mālama ʻana i ka wai i haumia me nā mea organik15,16.
Hiki i nā pūnaewele algae ke wehe i nā ion inorganic mai ka wai ma o ka biosorption a me ka hōʻiliʻili ʻana17,18. ʻO kekahi mau ʻano algal e like me Chlorella, Anabaena invar, Westiellopsis prolifica, Stigeoclonium tenue a me Synechococcus sp. Ua ʻike ʻia e lawe a hānai i nā ion metala ʻawahia e like me Fe2+, Cu2+, Zn2+ a me Mn2+19. Ua hōʻike ʻia nā haʻawina ʻē aʻe e kaupalena ana nā ion Cu2+, Cd2+, Ni2+, Zn2+ a i ʻole Pb2+ i ka ulu ʻana o Scenedesmus ma ka hoʻololi ʻana i ke ʻano o ke kelepona a me ka luku ʻana i kā lākou chloroplasts20,21.
Ua huki nā ʻano hana ʻōmaʻomaʻo no ka hoʻoheheʻe ʻana i nā mea haumia organik a me ka wehe ʻana i nā ion metala kaumaha i ka manaʻo o nā kānaka ʻepekema a me nā ʻenekinia a puni ka honua. ʻO ke kumu nui o kēia, ʻo ia ka maʻalahi o ka hana ʻana i kēia mau mea haumia i loko o ka pae wai. Eia nō naʻe, ua ʻike ʻia nā mea haumia crystalline inorganic e ka haʻahaʻa o ka solubility wai a me ka haʻahaʻa o ka hiki ke hoʻololi i nā biotransformations like ʻole, kahi e pilikia nui ai i ka hoʻoponopono ʻana, a ua liʻiliʻi ka holomua i hana ʻia ma kēia wahi22,23,24,25,26. No laila, ʻo ka ʻimi ʻana i nā hopena pili i ke kaiapuni no ka hoʻoponopono ʻana i nā nanomaterials he wahi paʻakikī a ʻaʻole i ʻimi ʻia. Ma muli o ke kiʻekiʻe o ka maopopo ʻole e pili ana i nā hopena biotransformation o nā nanomaterials 2D, ʻaʻohe ala maʻalahi e ʻike ai i nā ala hiki o ko lākou hōʻino ʻana i ka wā o ka hōʻemi ʻana.
Ma kēia haʻawina, ua hoʻohana mākou i ka microalgae ʻōmaʻomaʻo ma ke ʻano he mea hana bioremediation wai ikaika no nā mea seramika inorganic, i hui pū ʻia me ka nānā ʻana i loko o ke kaʻina hana degradation o MXene ma ke ʻano he ʻelele o nā mea seramika inorganic. Hōʻike ka huaʻōlelo "MXene" i ka stoichiometry o ka mea Mn+1XnTx, kahi ʻo M kahi metala hoʻololi mua, ʻo X ke kalapona a/a i ʻole nitrogen, ʻo Tx kahi terminator ʻili (eg, -OH, -F, -Cl), a me n = 1, 2, 3 a i ʻole 427.28. Mai ka ʻike ʻia ʻana o MXenes e Naguib et al. Sensorics, cancer therapy and membrane filtration 27,29,30. Eia kekahi, hiki ke noʻonoʻo ʻia ʻo MXenes he mau ʻōnaehana hoʻohālike 2D ma muli o ko lākou kūpaʻa colloidal maikaʻi loa a me nā pilina biological hiki ke hana ʻia31,32,33,34,35,36.
No laila, ua hōʻike ʻia ke ʻano hana i hoʻomohala ʻia ma kēia ʻatikala a me kā mākou mau kuhiakau noiʻi ma ke Kiʻi 1. Wahi a kēia kuhiakau, hoʻohaʻahaʻa ka microalgae i nā MXenes Nb-based i nā hui ʻawaʻawa ʻole ma muli o nā pilina physico-chemical e pili ana i ka ʻili, kahi e hiki ai ke hoʻōla hou i ka algae. No ka hoʻāʻo ʻana i kēia kuhiakau, ua koho ʻia ʻelua mau lālā o ka ʻohana o nā carbides metala hoʻololi mua a me/a i ʻole nā ​​​​nitrides (MXenes), ʻo ia hoʻi ʻo Nb2CTx a me Nb4C3TX.
ʻAno noiʻi a me nā kuhiakau i hoʻokumu ʻia i nā hōʻike no ka hoʻōla ʻana o MXene e ka microalgae ʻōmaʻomaʻo ʻo Raphidocelis subcapitata. E ʻoluʻolu e hoʻomaopopo he hōʻike hoʻolālā wale nō kēia o nā kuhiakau i hoʻokumu ʻia i nā hōʻike. ʻOkoʻa ke kaiapuni o ka loko i ka medium nutrient i hoʻohana ʻia a me nā kūlana (e laʻa, ka pōʻaiapuni diurnal a me nā palena i nā meaola koʻikoʻi i loaʻa). Hana ʻia me BioRender.com.
No laila, ma ka hoʻohana ʻana iā MXene ma ke ʻano he ʻōnaehana hoʻohālike, ua wehe mākou i ka puka i ke aʻo ʻana i nā hopena olaola like ʻole i hiki ʻole ke ʻike ʻia me nā nanomaterials maʻamau ʻē aʻe. Ma ke ʻano kūikawā, hōʻike mākou i ka hiki ke bioremediation o nā nanomaterials ʻelua-dimensional, e like me nā MXenes i hoʻokumu ʻia i ka niobium, e ka microalgae Raphidocelis subcapitata. Hiki i nā Microalgae ke hoʻohaʻahaʻa i nā Nb-MXenes i loko o nā oxides ʻawaʻawa ʻole NbO a me Nb2O5, kahi e hāʻawi pū ai i nā meaʻai ma o ka mīkini lawe ʻana o ka niobium. Ma keʻano holoʻokoʻa, pane kēia haʻawina i kahi nīnau koʻikoʻi koʻikoʻi e pili ana i nā kaʻina hana e pili ana i nā pilina physicochemical surface e hoʻomalu ana i nā ʻano hana o ka bioremediation o nā nanomaterials ʻelua-dimensional. Eia kekahi, ke hoʻomohala nei mākou i kahi ʻano hana maʻalahi e pili ana i ke ʻano no ka hahai ʻana i nā loli maalea i ke ʻano o nā nanomaterials 2D. Hoʻoulu kēia i ka noiʻi pōkole a me ka lōʻihi i nā hopena kaiapuni like ʻole o nā nanomaterials crystalline inorganic. No laila, hoʻonui kā mākou haʻawina i ka hoʻomaopopo ʻana i ka pilina ma waena o ka ʻili o ka mea a me ka mea olaola. Ke hāʻawi pū nei mākou i ke kumu no nā haʻawina pōkole a me ka wā lōʻihi e pili ana i ko lākou hopena i nā ʻōnaehana ola wai maʻemaʻe, hiki ke hōʻoia maʻalahi ʻia i kēia manawa.
Hōʻike nā MXenes i kahi papa hoihoi o nā mea me nā waiwai kino a me nā kemika kū hoʻokahi a nani hoʻi a no laila he nui nā noi hiki. Pili nui kēia mau waiwai i kā lākou stoichiometry a me ke kemika ʻili. No laila, i kā mākou noiʻi, ua noiʻi mākou i ʻelua ʻano o nā MXenes hierarchical single-layer (SL) Nb-based, ʻo Nb2CTx a me Nb4C3TX, ʻoiai hiki ke ʻike ʻia nā hopena olaola like ʻole o kēia mau nanomaterials. Hana ʻia nā MXenes mai kā lākou mau mea hoʻomaka ma o ka etching koho luna-i lalo o nā papa A MAX-phase lahilahi atomically. ʻO ka pae MAX kahi keramika ternary i haku ʻia me nā poloka "hoʻopaʻa" o nā carbides metala hoʻololi a me nā papa lahilahi o nā mea "A" e like me Al, Si, a me Sn me MnAXn-1 stoichiometry. Ua ʻike ʻia ke ʻano o ka pae MAX mua e ka microscopy electron scanning (SEM) a ua kūlike me nā haʻawina mua (E ʻike i ka ʻIke Hoʻohui, SI, Kiʻi S1). Ua loaʻa ka Multilayer (ML) Nb-MXene ma hope o ka wehe ʻana i ka papa Al me 48% HF (hydrofluoric acid). Ua nānā ʻia ke ʻano o ML-Nb2CTx a me ML-Nb4C3TX e ka microscopy electron scanning (SEM) (Nā Kiʻi S1c a me S1d) a ua ʻike ʻia kahi ʻano MXene papa maʻamau, e like me nā nanoflakes ʻelua-dimensional e hele ana ma o nā ʻoki elongated pore-like. He nui nā ʻano like o nā Nb-MXenes ʻelua me nā pae MXene i hana mua ʻia e ka etching acid27,38. Ma hope o ka hōʻoia ʻana i ke ʻano o MXene, ua hoʻopaʻa mākou iā ia ma o ka intercalation o tetrabutylammonium hydroxide (TBAOH) a ukali ʻia e ka holoi ʻana a me ka sonication, ma hope o ka loaʻa ʻana o nā nanoflakes 2D Nb-MXene papa hoʻokahi a i ʻole papa haʻahaʻa (SL).
Ua hoʻohana mākou i ka microscopy electron transmission hoʻonā kiʻekiʻe (HRTEM) a me ka diffraction X-ray (XRD) e hoʻāʻo i ka pono o ke kālai ʻana a me ka ʻili hou ʻana. Ua hōʻike ʻia nā hopena HRTEM i hana ʻia me ka hoʻohana ʻana i ka Inverse Fast Fourier Transform (IFFT) a me Fast Fourier Transform (FFT) ma ke Kiʻi 2. Ua hoʻonohonoho ʻia nā nanoflakes Nb-MXene i ka ʻaoʻao i luna e nānā i ke ʻano o ka papa atomika a ana i nā mamao interplanar. Ua hōʻike nā kiʻi HRTEM o nā nanoflakes MXene Nb2CTx a me Nb4C3TX i ko lākou ʻano lahilahi atomika (e nānā i ke Kiʻi 2a1, a2), e like me ka hōʻike mua ʻana a Naguib et al.27 a me Jastrzębska et al.38. No ʻelua mau monolayers Nb2CTx a me Nb4C3Tx e pili ana, ua hoʻoholo mākou i nā mamao interlayer o 0.74 a me 1.54 nm, kēlā me kēia (Kiʻi 2b1,b2), kahi e kūlike pū me kā mākou mau hopena ma mua38. Ua hōʻoia hou ʻia kēia e ka hoʻololi wikiwiki ʻana o Fourier (Kiʻi 2c1, c2) a me ka hoʻololi wikiwiki ʻana o Fourier (Kiʻi 2d1, d2) e hōʻike ana i ka mamao ma waena o nā monolayers Nb2CTx a me Nb4C3Tx. Hōʻike ke kiʻi i kahi hoʻololi o nā kāʻei mālamalama a me ka pouli e pili ana i nā ʻātoma niobium a me ke kalapona, e hōʻoia ana i ke ʻano papa o nā MXenes i aʻo ʻia. He mea nui e hoʻomaopopo ʻaʻole i hōʻike ka spectra spectroscopy X-ray dispersive ikehu (EDX) i loaʻa no Nb2CTx a me Nb4C3Tx (Nā Kiʻi S2a a me S2b) i ke koena o ka pae MAX mua, ʻoiai ʻaʻohe piko Al i ʻike ʻia.
ʻAno o nā nanoflakes SL Nb2CTx a me Nb4C3Tx MXene, me (a) ke kiʻi ʻana o ka microscopy electron hoʻonā kiʻekiʻe (HRTEM) ʻaoʻao-ʻike 2D nanoflake a me nā mea e pili ana, (b) ʻano ikaika, (c) hoʻololi Fourier wikiwiki inverse (IFFT), (d) hoʻololi Fourier wikiwiki (FFT), (e) nā hiʻohiʻona X-ray Nb-MXenes. No SL 2D Nb2CTx, ua hōʻike ʻia nā helu e like me (a1, b1, c1, d1, e1). No SL 2D Nb4C3Tx, ua hōʻike ʻia nā helu e like me (a2, b2, c2, d2, e1).
Ua hōʻike ʻia nā ana diffraction X-ray o SL Nb2CTx a me Nb4C3Tx MXenes ma nā Kiʻi 2e1 a me e2, kēlā me kēia. Pili nā Peaks (002) ma 4.31 a me 4.32 i nā MXenes papa i wehewehe mua ʻia ʻo Nb2CTx a me Nb4C3TX38,39,40,41. Hōʻike pū nā hopena XRD i ke alo o kekahi mau ʻano ML i koe a me nā pae MAX, akā ʻo ka hapa nui o nā hiʻohiʻona XRD e pili ana me SL Nb4C3Tx (Kiʻi 2e2). ʻO ke alo o nā ʻāpana liʻiliʻi o ka pae MAX e wehewehe paha i ka piko MAX ikaika i hoʻohālikelike ʻia me nā papa Nb4C3Tx i hoʻopaʻa ʻia ma ke ʻano random.
Ua kālele ʻia nā noiʻi hou aku i nā microalgae ʻōmaʻomaʻo no nā ʻano R. subcapitata. Ua koho mākou i nā microalgae no ka mea he mau mea hana koʻikoʻi lākou e pili ana i nā pūnaewele meaʻai nui42. ʻO lākou kekahi o nā hōʻailona maikaʻi loa o ka ʻawaʻawa ma muli o ka hiki ke wehe i nā mea ʻawaʻawa i lawe ʻia i nā pae kiʻekiʻe o ke kaulahao meaʻai43. Eia kekahi, hiki i ka noiʻi ʻana ma R. subcapitata ke hoʻomālamalama i ka ʻawaʻawa o SL Nb-MXenes i nā microorganism wai maʻemaʻe maʻamau. No ka hoʻākāka ʻana i kēia, ua kuhi nā mea noiʻi he ʻokoʻa ka ʻike o kēlā me kēia microbe i nā mea ʻawaʻawa i loaʻa i ke kaiapuni. No ka hapa nui o nā meaola, ʻaʻole pili nā haʻahaʻa haʻahaʻa o nā mea i ko lākou ulu ʻana, ʻoiai ʻo nā haʻahaʻa ma luna o kahi palena hiki ke kāohi iā lākou a i ʻole ke kumu o ka make. No laila, no kā mākou mau haʻawina e pili ana i ka pilina ʻili ma waena o microalgae a me MXenes a me ka hoʻōla hou ʻana, ua hoʻoholo mākou e hoʻāʻo i nā haʻahaʻa ʻino a me nā mea ʻawaʻawa o Nb-MXenes. No ka hana ʻana i kēia, ua hoʻāʻo mākou i nā ʻano o 0 (ma ke ʻano he kuhikuhi), 0.01, 0.1 a me 10 mg l-1 MXene a ua hoʻopili pū i ka microalgae me nā ʻano kiʻekiʻe loa o MXene (100 mg l-1 MXene), hiki ke lilo i mea koʻikoʻi a make. . no kekahi ʻano olaola.
Ua hōʻike ʻia nā hopena o SL Nb-MXenes ma nā microalgae ma ke Kiʻi 3, i hōʻike ʻia ma ke ʻano he pakeneka o ka hoʻolaha ulu (+) a i ʻole ka pale ʻana (-) i ana ʻia no nā laʻana 0 mg l-1. No ka hoʻohālikelike ʻana, ua hoʻāʻo ʻia hoʻi ka pae Nb-MAX a me ML Nb-MXenes a ua hōʻike ʻia nā hopena ma SI (e nānā i ke Kiʻi S3). Ua hōʻoia nā hopena i loaʻa ua aneane ʻole ka SL Nb-MXenes i ka ʻawahia ma ka pae o nā haʻahaʻa haʻahaʻa mai 0.01 a 10 mg/l, e like me ka mea i hōʻike ʻia ma ke Kiʻi 3a,b. I ke ʻano o Nb2CTx, ʻaʻole mākou i ʻike i ka ʻoi aku ma mua o 5% ecotoxicity ma ka pae i kuhikuhi ʻia.
Hoʻoulu (+) a i ʻole kāohi (-) o ka ulu ʻana o ka microalgae i ke alo o SL (a) Nb2CTx a me (b) Nb4C3TX MXene. Ua kālailai ʻia he 24, 48 a me 72 mau hola o ka pilina MXene-microalgae. Ua hōʻailona ʻia nā ʻikepili koʻikoʻi (t-test, p < 0.05) me kahi asterisk (*). Ua hōʻailona ʻia nā ʻikepili koʻikoʻi (t-test, p < 0.05) me kahi asterisk (*). Значимые данные (t-критерий, p < 0,05) отмечены звездочкой (*). Ua hōʻailona ʻia nā ʻikepili koʻikoʻi (t-test, p < 0.05) me kahi asterisk (*).重要数据（t 检验，p < 0.05）用星号(*) 标记。重要数据（t 检验，p < 0.05）用星号(*) 标记。 Важные данные (t-test, p < 0,05) отмечены звездочкой (*). Ua hōʻailona ʻia nā ʻikepili koʻikoʻi (t-test, p < 0.05) me kahi hōkū (*).Hōʻike nā pua ʻulaʻula i ka hoʻopau ʻia ʻana o ka hoʻoulu ʻana o ka inhibitory.
Ma ka ʻaoʻao ʻē aʻe, ua ʻoi aku ka ʻawaʻawa o nā haʻahaʻa haʻahaʻa o Nb4C3TX, akā ʻaʻole i ʻoi aku ma mua o 7%. E like me ka mea i manaʻo ʻia, ua ʻike mākou he ʻoi aku ka nui o ka ʻawaʻawa o MXenes a me ka pale ʻana i ka ulu ʻana o ka microalgae ma 100 mg L-1. ʻO ka mea hoihoi, ʻaʻohe o nā mea i hōʻike i ke ʻano like a me ka hilinaʻi manawa o nā hopena atoxic/ʻawaʻawa i hoʻohālikelike ʻia me nā laʻana MAX a i ʻole ML (e ʻike iā SI no nā kikoʻī). ʻOiai no ka pae MAX (e ʻike i ke Kiʻi S3) ua hiki ka ʻawaʻawa ma kahi o 15-25% a ua piʻi me ka manawa, ua ʻike ʻia ke ʻano ʻē aʻe no SL Nb2CTx a me Nb4C3TX MXene. Ua emi ka pale ʻana i ka ulu ʻana o ka microalgae i ka hala ʻana o ka manawa. Ua hiki i kahi o 17% ma hope o 24 mau hola a ua hāʻule i lalo o 5% ma hope o 72 mau hola (Kiʻi 3a, b, kēlā me kēia).
ʻOi aku ka mea nui, no SL Nb4C3TX, ua hōʻea ka pale ʻana o ka ulu ʻana o ka microalgae ma kahi o 27% ma hope o 24 mau hola, akā ma hope o 72 mau hola ua emi iho i kahi o 1%. No laila, ua kapa mākou i ka hopena i ʻike ʻia he pale ʻana i ka hoʻoulu ʻana, a ʻoi aku ka ikaika o ka hopena no SL Nb4C3TX MXene. Ua ʻike mua ʻia ka hoʻoulu ʻana o ka ulu ʻana o ka microalgae me Nb4C3TX (ka launa pū ʻana ma 10 mg L-1 no 24 h) i hoʻohālikelike ʻia me SL Nb2CTx MXene. Ua hōʻike maikaʻi ʻia ka hopena hoʻohuli ʻana o ka pale ʻana i ka hoʻoulu ʻana ma ke kaʻina hana pālua o ka biomass (e ʻike i ke Kiʻi S4 no nā kikoʻī). I kēia manawa, ua aʻo ʻia ka ecotoxicity o Ti3C2TX MXene ma nā ʻano like ʻole. ʻAʻole ia he mea ʻawaʻawa i nā embryos zebrafish44 akā he mea ʻawaʻawa iki i nā mea kanu microalgae Desmodesmus quadricauda a me Sorghum saccharatum45. ʻO nā hiʻohiʻona ʻē aʻe o nā hopena kikoʻī e pili ana i ka ʻawaʻawa kiʻekiʻe i nā laina cell cancer ma mua o nā laina cell maʻamau46,47. Hiki ke manaʻo ʻia e hoʻohuli nā kūlana hoʻāʻo i nā loli i ka ulu ʻana o ka microalgae i ʻike ʻia i ke alo o Nb-MXenes. No ka laʻana, ʻo ka pH ma kahi o 8 i loko o ka chloroplast stroma ka mea kūpono no ka hana pono o ka enzyme RuBisCO. No laila, hoʻopilikia maikaʻi ʻole nā ​​loli pH i ka wikiwiki o ka photosynthesis48,49. Eia naʻe, ʻaʻole mākou i ʻike i nā loli koʻikoʻi i ka pH i ka wā o ka hoʻokolohua (e ʻike iā SI, Fig. S5 no nā kikoʻī). Ma ke ʻano laulā, ua hoʻemi iki nā moʻomeheu o microalgae me Nb-MXenes i ka pH o ka hopena i ka hala ʻana o ka manawa. Eia naʻe, ua like kēia emi ʻana me ka loli o ka pH o kahi medium maʻemaʻe. Eia kekahi, ua like ka laulā o nā ʻokoʻa i loaʻa me ka mea i ana ʻia no kahi moʻomeheu maʻemaʻe o microalgae (laʻana kaohi). No laila, hoʻoholo mākou ʻaʻole i hoʻopilikia ʻia ka photosynthesis e nā loli o ka pH i ka hala ʻana o ka manawa.
Eia kekahi, loaʻa i nā MXenes i synthesized nā hopena ʻili (i hōʻike ʻia ʻo Tx). ʻO kēia nā hui hana nui -O, -F a me -OH. Eia nō naʻe, pili pono ke kemika ʻili i ke ʻano o ka synthesis. Ua ʻike ʻia kēia mau hui e hoʻolaha ʻia ma luna o ka ʻili, e paʻakikī ai ke wānana i ko lākou hopena ma nā waiwai o MXene50. Hiki ke hoʻopaʻapaʻa ʻia he hiki iā Tx ke lilo i ka ikaika catalytic no ka oxidation o ka niobium e ka mālamalama. Hāʻawi maoli nā hui hana ʻili i nā wahi hoʻopaʻa he nui no kā lākou photocatalysts ma lalo e hana i nā heterojunctions51. Eia naʻe, ʻaʻole i hāʻawi ka haku mele medium ulu i kahi photocatalyst maikaʻi (hiki ke loaʻa ka haku mele medium kikoʻī ma SI Table S6). Eia kekahi, he mea nui loa kekahi hoʻololi ʻili, no ka mea hiki ke hoʻololi ʻia ka hana olaola o MXenes ma muli o ka hana ʻana ma hope o ka papa, ka oxidation, ka hoʻololi ʻana o ka ʻili kemika o nā hui organik a me nā inorganic52,53,54,55,56 a i ʻole ka ʻenekinia hoʻouka ʻili38. No laila, no ka hoʻāʻo ʻana inā pili ka niobium oxide i ka paʻa ʻole o nā mea i loko o ka medium, ua hana mākou i nā haʻawina o ka zeta (ζ) potential i loko o ka microalgae growth medium a me ka wai deionized (no ka hoʻohālikelike). Hōʻike kā mākou mau hopena he paʻa loa nā SL Nb-MXenes (e nānā i ke Kiʻi SI S6 no nā hopena MAX a me ML). ʻO ka zeta potential o SL MXenes ma kahi o -10 mV. I ke ʻano o SR Nb2CTx, ʻoi aku ka maikaʻi ʻole o ka waiwai o ζ ma mua o Nb4C3Tx. ʻO ia ʻano hoʻololi i ka waiwai ζ e hōʻike paha e omo ka ʻili o nā nanoflakes MXene i hoʻopiʻi maikaʻi ʻole ʻia i nā ions i hoʻopiʻi maikaʻi ʻia mai ka medium culture. ʻO nā ana manawa o ka zeta potential a me ka conductivity o Nb-MXenes i ka medium culture (e nānā i nā Kiʻi S7 a me S8 ma SI no nā kikoʻī hou aku) me he mea lā e kākoʻo ana i kā mākou kuhiakau.
Eia nō naʻe, ua hōʻike nā Nb-MXene SL ʻelua i nā loli liʻiliʻi mai ka ʻole. Hōʻike maopopo kēia i ko lākou kūpaʻa i loko o ka medium ulu microalgae. Eia kekahi, ua loiloi mākou inā e hoʻopilikia ka loaʻa ʻana o kā mākou microalgae ʻōmaʻomaʻo i ke kūpaʻa o Nb-MXenes i loko o ka medium. Hiki ke loaʻa nā hopena o ka zeta potential a me ka conductivity o MXenes ma hope o ka launa pū ʻana me microalgae i loko o nā media nutrient a me ka moʻomeheu i ka hala ʻana o ka manawa ma SI (Nā Kiʻi S9 a me S10). ʻO ka mea hoihoi, ua ʻike mākou ua like ka loaʻa ʻana o ka microalgae me he mea lā ua hoʻopaʻa i ka hoʻopuehu ʻana o nā MXenes ʻelua. I ke ʻano o Nb2CTx SL, ua emi iki ka zeta potential i ka hala ʻana o ka manawa i nā waiwai maikaʻi ʻole (-15.8 versus -19.1 mV ma hope o 72 h o ka incubation). Ua piʻi iki ka zeta potential o SL Nb4C3TX, akā ma hope o 72 h ua hōʻike mau ia i ke kūpaʻa kiʻekiʻe ma mua o nā nanoflakes me ka ʻole o ka microalgae (-18.1 vs. -9.1 mV).
Ua ʻike pū mākou i ka conductivity haʻahaʻa o nā hopena Nb-MXene i hoʻoulu ʻia i ke alo o ka microalgae, e hōʻike ana i ka nui o nā ions i loko o ka medium nutrient. ʻO ka mea nui, ʻo ka paʻa ʻole o MXenes i ka wai ma muli o ka oxidation o ka ʻili57. No laila, ke manaʻo nei mākou ua hoʻomaʻemaʻe kekahi ʻano microalgae ʻōmaʻomaʻo i nā oxides i hana ʻia ma ka ʻili o Nb-MXene a pale aku i ko lākou hanana ʻana (oxidation o MXene). Hiki ke ʻike ʻia kēia ma ke aʻo ʻana i nā ʻano mea i omo ʻia e ka microalgae.
ʻOiai ua hōʻike kā mākou mau haʻawina ecotoxicological ua hiki i ka microalgae ke lanakila i ka ʻawaʻawa o Nb-MXenes i ka hala ʻana o ka manawa a me ka pale ʻana i ka ulu ʻana o ka ulu ʻana, ʻo ka pahuhopu o kā mākou noiʻi ʻana, ʻo ia ke noiʻi i nā ʻano hana hiki. Ke hōʻike ʻia nā meaola e like me ka algae i nā hui a i ʻole nā ​​​​mea i kamaʻāina ʻole i kā lākou ʻōnaehana ola, hiki iā lākou ke pane ma nā ʻano like ʻole58,59. I ka loaʻa ʻole o nā oxides metala ʻawaʻawa, hiki i ka microalgae ke hānai iā lākou iho, e ʻae ana iā lākou e ulu mau60. Ma hope o ka ʻai ʻana i nā mea ʻawaʻawa, hiki ke hoʻāla ʻia nā ʻano pale, e like me ka hoʻololi ʻana i ke ʻano a i ʻole ke ʻano. Pono hoʻi e noʻonoʻo ʻia ka hiki ke omo ʻia58,59. ʻO ka mea nui, ʻo kekahi hōʻailona o kahi ʻano pale he hōʻailona maopopo ia o ka ʻawaʻawa o ka hui hoʻāʻo. No laila, i kā mākou hana hou aku, ua noiʻi mākou i ka pilina o ka ʻili ma waena o nā nanoflakes SL Nb-MXene a me microalgae e SEM a me ka hiki ke omo ʻia o Nb-based MXene e ka X-ray fluorescence spectroscopy (XRF). E hoʻomaopopo ua hana wale ʻia nā loiloi SEM a me XRF ma ka nui kiʻekiʻe loa o MXene e hoʻoponopono i nā pilikia ʻawaʻawa hana.
Ua hōʻike ʻia nā hopena SEM ma ke Kiʻi 4. Ua hōʻike maopopo nā pūnaewele microalgae i mālama ʻole ʻia (e nānā i ke Kiʻi 4a, laʻana kuhikuhi) i ke ʻano maʻamau o R. subcapitata a me ke ʻano o ke kelepona e like me ka croissant. ʻIke ʻia nā kelepona ua pālahalaha a hoʻonohonoho iki ʻia. Ua uhi ʻia kekahi mau kelepona microalgae a ua hihia kekahi me kekahi, akā ua hana ʻia paha kēia e ke kaʻina hana hoʻomākaukau laʻana. Ma keʻano laulā, he ʻili laumania ko nā kelepona microalgae maʻemaʻe a ʻaʻole i hōʻike i nā loli morphological.
Nā kiʻi SEM e hōʻike ana i ka pilina ʻili ma waena o ka microalgae ʻōmaʻomaʻo a me nā nanosheets MXene ma hope o 72 mau hola o ka launa pū ʻana ma ka nui loa (100 mg L-1). (a) Microalgae ʻōmaʻomaʻo i mālama ʻole ʻia ma hope o ka launa pū ʻana me SL (b) Nb2CTx a me (c) Nb4C3TX MXenes. E hoʻomaopopo ua hōʻailona ʻia nā nanoflakes Nb-MXene me nā pua ʻulaʻula. No ka hoʻohālikelike ʻana, ua hoʻohui pū ʻia nā kiʻi mai kahi microscope optical.
I ka hoʻohālikelike ʻana, ua hōʻino ʻia nā pūnaewele microalgae i hoʻopili ʻia e nā nanoflakes SL Nb-MXene (e nānā i ke Kiʻi 4b, c, nā pua ʻulaʻula). I ke ʻano o Nb2CTx MXene (Kiʻi 4b), ulu pinepine nā microalgae me nā nanoscales ʻelua-dimensional i hoʻopili ʻia, hiki ke hoʻololi i ko lākou morphology. ʻIke ʻia, ua ʻike pū mākou i kēia mau loli ma lalo o ka microscopy māmā (e nānā i ke Kiʻi SI S11 no nā kikoʻī). Loaʻa i kēia hoʻololi morphological kahi kumu kūpono i ka physiology o microalgae a me ko lākou hiki ke pale aku iā lākou iho ma ka hoʻololi ʻana i ke ʻano o ke kelepona, e like me ka hoʻonui ʻana i ka nui o ke kelepona61. No laila, he mea nui e nānā i ka helu o nā pūnaewele microalgae e pili pono ana me Nb-MXenes. Ua hōʻike ʻia nā haʻawina SEM ua hōʻike ʻia ma kahi o 52% o nā pūnaewele microalgae i nā Nb-MXenes, ʻoiai 48% o kēia mau pūnaewele microalgae i pale aku i ka hoʻopili ʻana. No SL Nb4C3Tx MXene, hoʻāʻo nā microalgae e pale aku i ka hoʻopili ʻana me MXene, no laila e kūloko ana a ulu ana mai nā nanoscales ʻelua-dimensional (Kiʻi 4c). Eia nō naʻe, ʻaʻole mākou i ʻike i ke komo ʻana o nā nanoscales i loko o nā pūnaewele microalgae a me ko lākou hōʻino.
ʻO ka mālama ponoʻī ʻana he ʻano pane e pili ana i ka manawa i ka pale ʻana o ka photosynthesis ma muli o ka adsorption o nā ʻāpana ma ka ʻili o ke kelepona a me ka mea i kapa ʻia ʻo shading (shading) effect62. Ua maopopo he palena kēlā me kēia mea (no ka laʻana, ʻo Nb-MXene nanoflakes) aia ma waena o ka microalgae a me ke kumu kukui i ka nui o ka mālamalama i omo ʻia e nā chloroplasts. Eia naʻe, ʻaʻohe o mākou kānalua he hopena koʻikoʻi kēia i nā hopena i loaʻa. E like me ka mea i hōʻike ʻia e kā mākou mau nānā microscopic, ʻaʻole i ʻōwili piha ʻia a hoʻopili ʻia paha nā nanoflakes 2D i ka ʻili o ka microalgae, ʻoiai i ka wā e pili ana nā cell microalgae me Nb-MXenes. Akā, ua huli ʻia nā nanoflakes i kuhikuhi ʻia i nā cell microalgae me ka uhi ʻole ʻana i ko lākou ʻili. ʻAʻole hiki i kēlā ʻano o nā nanoflakes/microalgae ke kaupalena nui i ka nui o ka mālamalama i omo ʻia e nā cell microalgae. Eia kekahi, ua hōʻike kekahi mau haʻawina i ka hoʻomaikaʻi ʻana i ka omo ʻana o ka mālamalama e nā meaola photosynthetic i ke alo o nā nanomaterials ʻelua-dimensional63,64,65,66.
ʻOiai ʻaʻole hiki i nā kiʻi SEM ke hōʻoia pololei i ka lawe ʻana o ka niobium e nā cell microalgae, ua huli kā mākou noiʻi hou aku i ka X-ray fluorescence (XRF) a me ka loiloi X-ray photoelectron spectroscopy (XPS) e wehewehe i kēia pilikia. No laila, ua hoʻohālikelike mākou i ka ikaika o nā piko Nb o nā laʻana microalgae kuhikuhi i launa ʻole me MXenes, nā nanoflakes MXene i hoʻokaʻawale ʻia mai ka ʻili o nā cell microalgae, a me nā cell microalgal ma hope o ka wehe ʻana i nā MXenes i hoʻopili ʻia. He mea kūpono ke hoʻomaopopo ʻana inā ʻaʻohe lawe ʻana o Nb, pono ka waiwai Nb i loaʻa i nā cell microalgae i ka zero ma hope o ka wehe ʻana i nā nanoscales i hoʻopili ʻia. No laila, inā hana ʻia ka lawe ʻana o Nb, pono e hōʻike nā hopena XRF a me XPS i kahi piko Nb maopopo.
I ke ʻano o nā spectra XRF, ua hōʻike nā hāpana microalgae i nā piko Nb no SL Nb2CTx a me Nb4C3Tx MXene ma hope o ka launa pū ʻana me SL Nb2CTx a me Nb4C3Tx MXene (e nānā i ke Kiʻi 5a, e hoʻomaopopo hoʻi ua hōʻike ʻia nā hopena no MAX a me ML MXenes ma SI, Figs S12–C17). ʻO ka mea hoihoi, ua like ka ikaika o ka piko Nb ma nā hihia ʻelua (nā kaha ʻulaʻula ma ke Kiʻi 5a). Ua hōʻike kēia ʻaʻole hiki i ka algae ke omo i ka Nb hou aku, a ua hoʻokō ʻia ka hiki ke hoʻonui ʻia ka Nb i loko o nā cell, ʻoiai ua hoʻopili ʻia ʻelua mau manawa ʻoi aku ka nui o Nb4C3Tx MXene i nā cell microalgae (nā kaha polū ma ke Kiʻi 5a). ʻO ka mea nui, ʻo ka hiki o ka microalgae ke omo i nā metala e pili ana i ka nui o nā oxides metala i ke kaiapuni67,68. Ua ʻike ʻo Shamshada et al.67 e emi ana ka hiki ke omo o ka algae wai maʻemaʻe me ka hoʻonui ʻana o ka pH. Ua ʻike ʻo Raize et al.68 ʻo ka hiki o ka limu ke omo i nā metala ma kahi o 25% kiʻekiʻe no Pb2+ ma mua o Ni2+.
(a) Nā hopena XRF o ka lawe ʻana o ka Nb basal e nā cell microalgae ʻōmaʻomaʻo i hoʻoulu ʻia ma kahi nui loa o SL Nb-MXenes (100 mg L-1) no 72 mau hola. Hōʻike nā hopena i ke alo o α i loko o nā cell microalgae maʻemaʻe (laʻana hoʻomalu, nā kolamu hina), nā nanoflakes 2D i hoʻokaʻawale ʻia mai nā cell microalgae ʻili (nā kolamu polū), a me nā cell microalgae ma hope o ka hoʻokaʻawale ʻana o nā nanoflakes 2D mai ka ʻili (nā kolamu ʻulaʻula). ʻO ka nui o ka elemental Nb, (b) pakeneka o ka haku mele kemika o nā ʻāpana organik microalgae (C=O a me CHx/C–O) a me nā oxides Nb i loaʻa i loko o nā cell microalgae ma hope o ka hoʻoulu ʻana me SL Nb-MXenes, (c–e) Ke kūpono ʻana o ka piko haku mele o XPS SL Nb2CTx spectra a me (fh) SL Nb4C3Tx MXene i hoʻokomo ʻia e nā cell microalgae.
No laila, ua manaʻo mākou e hiki ke omo ʻia ʻo Nb e nā pūnaewele algal ma ke ʻano o nā oxides. No ka hoʻāʻo ʻana i kēia, ua hana mākou i nā haʻawina XPS ma nā MXenes Nb2CTx a me Nb4C3TX a me nā pūnaewele algae. Hōʻike ʻia nā hopena o ka launa pū ʻana o ka microalgae me Nb-MXenes a me MXenes i hoʻokaʻawale ʻia mai nā pūnaewele algae ma nā Kiʻi 5b. E like me ka mea i manaʻo ʻia, ua ʻike mākou i nā piko Nb 3d i loko o nā laʻana microalgae ma hope o ka wehe ʻana o MXene mai ka ʻili o ka microalgae. Ua helu ʻia ka hoʻoholo quantitative o C=O, CHx/CO, a me Nb oxides ma muli o nā spectra Nb 3d, O 1s, a me C 1s i loaʻa me Nb2CTx SL (Kiʻi 5c–e) a me Nb4C3Tx SL (Kiʻi 5c–e). ) i loaʻa mai ka microalgae i hoʻoulu ʻia. Kiʻi 5f–h) MXenes. Hōʻike ka Papa S1-3 i nā kikoʻī o nā palena piko a me ke kemika holoʻokoʻa i loaʻa mai ke kūpono. He mea kūpono ke hoʻomaopopo ʻia ʻo nā ʻāpana Nb 3d o Nb2CTx SL a me Nb4C3Tx SL (Kiʻi 5c, f) e pili ana i hoʻokahi ʻāpana Nb2O5. Maanei, ʻaʻole mākou i ʻike i nā piko e pili ana iā MXene i loko o nā spectra, e hōʻike ana e omo wale nā ​​​​​​kelepona microalgae i ke ʻano oxide o Nb. Eia kekahi, ua hoʻokokoke mākou i ka spectrum C 1 s me nā ʻāpana C – C, CHx / C – O, C = O, a me –COOH. Ua hāʻawi mākou i nā piko CHx / C – O a me C = O i ka hāʻawi organik o nā cell microalgae. ʻO kēia mau ʻāpana organik no 36% a me 41% o nā piko C 1s ma Nb2CTx SL a me Nb4C3TX SL, kēlā me kēia. A laila ua hoʻokomo mākou i nā spectra O 1s o SL Nb2CTx a me SL Nb4C3TX me Nb2O5, nā ʻāpana organik o microalgae (CHx / CO), a me ka wai i hoʻopili ʻia ma luna.
ʻO ka mea hope loa, ua hōʻike maopopo nā hopena XPS i ke ʻano o Nb, ʻaʻole wale kona alo. Wahi a ke kūlana o ka hōʻailona Nb 3d a me nā hopena o ka deconvolution, ke hōʻoia nei mākou ua omo wale ʻia ʻo Nb ma ke ʻano o nā oxides a ʻaʻole nā ​​​​ions a i ʻole MXene ponoʻī. Eia kekahi, ua hōʻike nā hopena XPS he hiki i nā cell microalgae ke lawe i nā oxides Nb mai SL Nb2CTx i hoʻohālikelike ʻia me SL Nb4C3TX MXene.
ʻOiai he mea kupaianaha kā mākou mau hopena lawe ʻana o Nb a hiki iā mākou ke ʻike i ka hoʻohaʻahaʻa ʻana o MXene, ʻaʻohe ala i loaʻa e hahai i nā loli morphological pili i nā nanoflakes 2D. No laila, ua hoʻoholo pū mākou e hoʻomohala i kahi ala kūpono e hiki ke pane pololei i nā loli e hana nei i nā nanoflakes 2D Nb-MXene a me nā cell microalgae. He mea nui e hoʻomaopopo e manaʻo mākou inā e hana nā ʻano e launa pū ana i kekahi hoʻololi, decomposition a defragmentation paha, pono e hōʻike koke ʻia kēia ma ke ʻano he mau loli i nā ʻano ʻano, e like me ke anawaena o ka ʻāpana poepoe like, ka poepoe, ka laulā o Feret, a i ʻole ka lōʻihi o Feret. No ka mea, kūpono kēia mau ʻano no ka wehewehe ʻana i nā ʻāpana elongated a i ʻole nā ​​nanoflakes ʻelua-dimensional, ʻo kā lākou hahai ʻana ma o ka nānā ʻana i ke ʻano o nā ʻāpana dynamic e hāʻawi iā mākou i ka ʻike waiwai e pili ana i ka hoʻololi morphological o nā nanoflakes SL Nb-MXene i ka wā o ka hōʻemi ʻana.
Ua hōʻike ʻia nā hopena i loaʻa ma ke Kiʻi 6. No ka hoʻohālikelike ʻana, ua hoʻāʻo pū mākou i ka pae MAX mua a me ML-MXenes (e ʻike i nā Kiʻi SI S18 a me S19). Ua hōʻike ka loiloi ikaika o ke ʻano o ka ʻāpana i ua loli nui nā ʻano āpau o ʻelua Nb-MXene SLs ma hope o ka launa pū ʻana me ka microalgae. E like me ka mea i hōʻike ʻia e ka ʻano like o ke anawaena o ka wahi pōʻai (Kiʻi 6a, b), ʻo ka emi ʻana o ka ikaika o ka piko o ka hapa o nā nanoflakes nui e hōʻike ana e palaho lākou i nā ʻāpana liʻiliʻi. Ma ke kiʻi 6c, hōʻike ʻo d i ka emi ʻana o nā piko e pili ana me ka nui transverse o nā flakes (elongation o nā nanoflakes), e hōʻike ana i ka hoʻololi ʻana o nā nanoflakes 2D i kahi ʻano like me ka ʻāpana. Hōʻike ke Kiʻi 6e-h i ka laulā a me ka lōʻihi o ka Feret, kēlā me kēia. ʻO ka laulā a me ka lōʻihi o Feret he mau ʻano hoʻopihapiha a no laila e noʻonoʻo pū ʻia. Ma hope o ka hoʻoulu ʻana o nā nanoflakes 2D Nb-MXene i ke alo o ka microalgae, ua neʻe ko lākou mau piko pilina Feret a ua emi ko lākou ikaika. Ma muli o kēia mau hopena i hui pū ʻia me ke ʻano, XRF a me XPS, ua hoʻoholo mākou e pili pono ana nā loli i ʻike ʻia i ka oxidation i ka wā e lilo ai nā MXenes i oxidized i ʻoi aku ka wrinkled a wāwahi i loko o nā ʻāpana a me nā ʻāpana oxide poepoe69,70.
ʻO ka loiloi o ka hoʻololi ʻana o MXene ma hope o ka launa pū ʻana me ka microalgae ʻōmaʻomaʻo. Hoʻomaopopo ka loiloi ʻano ʻāpana ikaika i nā palena e like me (a, b) ke anawaena o ka ʻāpana poepoe like, (c, d) ka poepoe, (e, f) ka laulā o Feret a me (g, h) ka lōʻihi o Feret. No kēia hopena, ua loiloi ʻia ʻelua mau laʻana microalgae kuhikuhi me nā SL Nb2CTx mua a me SL Nb4C3Tx MXenes, SL Nb2CTx a me SL Nb4C3Tx MXenes, microalgae i hoʻohaʻahaʻa ʻia, a me nā microalgae i mālama ʻia ʻo SL Nb2CTx a me SL Nb4C3Tx MXenes. Hōʻike nā pua ʻulaʻula i nā hoʻololi o nā palena ʻano o nā nanoflakes ʻelua-dimensional i aʻo ʻia.
ʻOiai he hilinaʻi loa ka nānā ʻana i nā ʻano o ke ʻano, hiki iā ia ke hōʻike i nā loli morphological i nā cell microalgae. No laila, ua kālailai mākou i ke anawaena like o ka ʻāpana poepoe, ka poepoe, a me ka laulā/lōʻihi o Feret o nā cell microalgae maʻemaʻe a me nā cell ma hope o ka launa pū ʻana me nā nanoflakes 2D Nb. Ma ke kiʻi 6a-h e hōʻike i nā loli i nā ʻano o ke ʻano o nā cell algae, e like me ka hōʻike ʻana e ka emi ʻana o ka ikaika kiʻekiʻe a me ka neʻe ʻana o ka maxima i nā waiwai kiʻekiʻe. Ma ke ʻano kūikawā, ua hōʻike nā ʻano poepoe cell i ka emi ʻana o nā cell elongated a me ka piʻi ʻana o nā cell spherical (Kiʻi 6a, b). Eia kekahi, ua hoʻonui ʻia ka laulā o nā cell Feret e kekahi mau micrometers ma hope o ka launa pū ʻana me SL Nb2CTx MXene (Kiʻi 6e) i hoʻohālikelike ʻia me SL Nb4C3TX MXene (Kiʻi 6f). Manaʻo mākou he kumu paha kēia o ka lawe ikaika ʻana o nā oxides Nb e ka microalgae ma hope o ka launa pū ʻana me Nb2CTx SR. ʻO ka hoʻopili ʻana o nā flakes Nb i ko lākou ʻili e hiki ke hopena i ka ulu ʻana o nā cell me ka hopena shading liʻiliʻi.
ʻO kā mākou nānā ʻana i nā loli i nā palena o ke ʻano a me ka nui o ka microalgae e hoʻokō i nā haʻawina ʻē aʻe. Hiki i ka microalgae ʻōmaʻomaʻo ke hoʻololi i ko lākou morphology i ka pane ʻana i ke kaumaha o ke kaiapuni ma o ka hoʻololi ʻana i ka nui o ke kelepona, ke ʻano a i ʻole ka metabolism61. No ka laʻana, ʻo ka hoʻololi ʻana i ka nui o nā kelepona e hoʻomaʻamaʻa i ka omo ʻana o nā meaʻai71. Hōʻike nā kelepona algae liʻiliʻi i ka lawe ʻana o nā meaʻai haʻahaʻa a me ka wikiwiki o ka ulu ʻana. I ka ʻaoʻao ʻē aʻe, ʻoi aku ka nui o nā kelepona nui e ʻai i nā meaʻai hou aku, a laila waiho ʻia ma loko o ka cell72,73. Ua ʻike ʻo Machado lāua ʻo Soares hiki i ka fungicide triclosan ke hoʻonui i ka nui o nā kelepona. Ua ʻike pū lākou i nā loli koʻikoʻi i ke ʻano o ka algae74. Eia kekahi, ua hōʻike pū ʻo Yin et al.9 i nā loli morphological i ka algae ma hope o ka hōʻike ʻana i nā nanocomposites graphene oxide i hoʻemi ʻia. No laila, ua maopopo he kumu ʻia nā palena nui/ʻano i hoʻololi ʻia o ka microalgae e ke alo o MXene. ʻOiai ʻo kēia loli i ka nui a me ke ʻano he hōʻike ia o nā loli i ka lawe ʻana o nā meaʻai, ke manaʻoʻiʻo nei mākou e hiki i ka nānā ʻana i nā palena nui a me ke ʻano i ka hala ʻana o ka manawa ke hōʻike i ka lawe ʻana o ka niobium oxide e ka microalgae i ke alo o Nb-MXenes.
Eia kekahi, hiki ke hoʻoheheʻe ʻia nā MXenes i ke alo o ka algae. Ua ʻike ʻo Dalai et al.75 ʻaʻole like ke ʻano o ka algae ʻōmaʻomaʻo i hōʻike ʻia i ka nano-TiO2 a me Al2O376. ʻOiai ua like kā mākou mau nānā ʻana me ke aʻo ʻana o kēia manawa, pili wale ia i ke aʻo ʻana i nā hopena o ka bioremediation ma ke ʻano o nā huahana degradation MXene i ke alo o nā nanoflakes 2D a ʻaʻole nā ​​​​nanoparticles. ʻOiai hiki i nā MXenes ke hoʻohaʻahaʻa i nā oxides metala,31,32,77,78 he mea kūpono ke manaʻo e hiki i kā mākou Nb nanoflakes ke hana i nā Nb oxides ma hope o ka launa pū ʻana me nā cell microalgae.
I mea e wehewehe ai i ka hōʻemi ʻana o nā nanoflakes 2D-Nb ma o kahi ʻano hana decomposition e pili ana i ke kaʻina hana oxidation, ua hana mākou i nā haʻawina e hoʻohana ana i ka microscopy electron transmission high-resolution (HRTEM) (Kiʻi 7a,b) a me ka X-ray photoelectron spectroscopy (XPS) (Kiʻi 7). 7c-i a me nā papa S4-5). He kūpono nā ʻano ʻelua no ke aʻo ʻana i ka oxidation o nā mea 2D a hoʻokō kekahi i kekahi. Hiki iā HRTEM ke kālailai i ka hōʻino ʻana o nā ʻano papa ʻelua-dimensional a me ke ʻano ma hope o nā nanoparticles oxide metala, ʻoiai ʻo XPS ka mea naʻau i nā pilina ʻili. No kēia kumu, ua hoʻāʻo mākou i nā nanoflakes 2D Nb-MXene i unuhi ʻia mai nā dispersions cell microalgae, ʻo ia hoʻi, ko lākou ʻano ma hope o ka launa pū ʻana me nā cell microalgae (e ʻike i ke Kiʻi 7).
Nā kiʻi HRTEM e hōʻike ana i ke ʻano o ka oxidized (a) SL Nb2CTx a me (b) SL Nb4C3Tx MXenes, nā hopena loiloi XPS e hōʻike ana (c) i ka haku mele ʻana o nā huahana oxide ma hope o ka hōʻemi ʻana, (d–f) ka hoʻohālikelike piko o nā ʻāpana o nā spectra XPS o SL Nb2CTx a me (g– i) Nb4C3Tx SL i hoʻoponopono ʻia me ka microalgae ʻōmaʻomaʻo.
Ua hōʻoia nā haʻawina HRTEM i ka oxidation o ʻelua ʻano o nā nanoflakes Nb-MXene. ʻOiai ua mālama nā nanoflakes i ko lākou ʻano ʻelua-dimensional i kekahi ʻano, ua hopena ka oxidation i ka ʻike ʻia ʻana o nā nanoparticles he nui e uhi ana i ka ʻili o nā nanoflakes MXene (e nānā i ke Kiʻi 7a,b). Ua hōʻike ka loiloi XPS o nā hōʻailona c Nb 3d a me O 1s ua hoʻokumu ʻia nā oxides Nb i nā hihia ʻelua. E like me ka mea i hōʻike ʻia ma ke Kiʻi 7c, loaʻa i nā hōʻailona Nb 3d o 2D MXene Nb2CTx a me Nb4C3TX e hōʻike ana i ke alo o nā oxides NbO a me Nb2O5, ʻoiai nā hōʻailona O 1s e hōʻike ana i ka helu o nā pilina O-Nb e pili ana me ka hana ʻana o ka ʻili nanoflake 2D. Ua ʻike mākou he nui ka hāʻawi ʻana o ka oxide Nb i hoʻohālikelike ʻia me Nb-C a me Nb3+-O.
Ma ke kiʻi. Hōʻike nā kiʻi 7g–i i nā spectra XPS o Nb 3d, C 1s, a me O 1s SL Nb2CTx (e nānā i nā Kiʻi 7d–f) a me SL Nb4C3TX MXene i hoʻokaʻawale ʻia mai nā cell microalgae. Hāʻawi ʻia nā kikoʻī o nā palena kiʻekiʻe Nb-MXenes ma nā Papa S4–5, kēlā me kēia. Ua kālailai mua mākou i ka haku mele ʻana o Nb 3d. I ka hoʻohālikelike ʻana me Nb i omo ʻia e nā cell microalgae, ma MXene i hoʻokaʻawale ʻia mai nā cell microalgae, ma waho aʻe o Nb2O5, ua loaʻa nā ʻāpana ʻē aʻe. Ma ka Nb2CTx SL, ua ʻike mākou i ka hāʻawi ʻana o Nb3+-O ma ka nui o 15%, ʻoiai ʻo ke koena o ka spectrum Nb 3d i noho aliʻi ʻia e Nb2O5 (85%). Eia kekahi, aia ka laʻana SL Nb4C3TX i nā ʻāpana Nb-C (9%) a me Nb2O5 (91%). Maanei, hele mai ʻo Nb-C mai ʻelua mau papa atomika o loko o ka carbide metala ma Nb4C3Tx SR. A laila hoʻohālikelike mākou i nā spectra C 1s i ʻehā mau ʻāpana like ʻole, e like me kā mākou i hana ai i nā laʻana i hoʻokomo ʻia. E like me ka mea i manaʻo ʻia, ua hoʻomalu ʻia ka spectrum C 1s e ke kalapona graphitic, ukali ʻia e nā haʻawina mai nā ʻāpana organik (CHx/CO a me C=O) mai nā cell microalgae. Eia kekahi, ma ka spectrum O 1s, ua ʻike mākou i ka haʻawina o nā ʻano organik o nā cell microalgae, niobium oxide, a me ka wai i hoʻomoʻa ʻia.
Eia kekahi, ua noiʻi mākou inā pili ka ʻoki ʻana o Nb-MXenes me ke alo o nā ʻano oxygen reactive (ROS) i loko o ka medium nutrient a/a i ʻole nā ​​​​​​cell microalgae. No kēia hopena, ua loiloi mākou i nā pae o ka oxygen singlet (1O2) i loko o ka medium culture a me ka glutathione intracellular, kahi thiol e hana ma ke ʻano he antioxidant i loko o ka microalgae. Hōʻike ʻia nā hopena ma SI (Nā Kiʻi S20 a me S21). Ua hōʻike ʻia nā moʻomeheu me SL Nb2CTx a me Nb4C3TX MXenes e ka nui o 1O2 i hoʻemi ʻia (e nānā i ke Kiʻi S20). I ke ʻano o SL Nb2CTx, ua hoʻemi ʻia ʻo MXene 1O2 i kahi o 83%. No nā moʻomeheu microalgae e hoʻohana ana iā SL, ua emi hou aku ʻo Nb4C3TX 1O2, i 73%. ʻO ka mea hoihoi, ua hōʻike nā loli i ka 1O2 i ke ʻano like me ka hopena inhibitory-stimulatory i ʻike mua ʻia (e nānā i ke Kiʻi 3). Hiki ke hoʻopaʻapaʻa ʻia e hiki i ka incubation i ka mālamalama mālamalama ke hoʻololi i ka photooxidation. Eia nō naʻe, ua hōʻike nā hopena o ka loiloi kaohi i nā pae kokoke mau o 1O2 i ka wā o ka hoʻokolohua (Kiʻi S22). I ke ʻano o nā pae ROS intracellular, ua ʻike pū mākou i ke ʻano like o lalo (e nānā i ke Kiʻi S21). I ka wā mua, ua ʻoi aku ka nui o nā pae o ROS i loko o nā cell microalgae i mahi ʻia i ke alo o Nb2CTx a me Nb4C3Tx SLs ma mua o nā pae i loaʻa i nā moʻomeheu maʻemaʻe o microalgae. I ka hopena, akā naʻe, ua ʻike ʻia ua hoʻololi ka microalgae i ke alo o nā Nb-MXenes ʻelua, ʻoiai ua emi nā pae ROS i 85% a me 91% o nā pae i ana ʻia i nā moʻomeheu maʻemaʻe o microalgae i hoʻopili ʻia me SL Nb2CTx a me Nb4C3TX, kēlā me kēia. Hōʻike paha kēia e ʻoluʻolu ka microalgae i ka hala ʻana o ka manawa i ke alo o Nb-MXene ma mua o ka medium nutrient wale nō.
He hui like ʻole nā ​​​​microalgae o nā meaola photosynthetic. I ka wā o ka photosynthesis, hoʻololi lākou i ke kalapona dioxide lewa (CO2) i kalapona organik. ʻO nā huahana o ka photosynthesis he glucose a me ka oxygen79. Manaʻo mākou he kuleana koʻikoʻi ka oxygen i hoʻokumu ʻia i ka oxidation o Nb-MXenes. ʻO kahi wehewehe hiki no kēia, ʻo ia ka hoʻokumu ʻia ʻana o ka parameter aeration ʻokoʻa ma nā kaomi hapa haʻahaʻa a kiʻekiʻe o ka oxygen ma waho a ma loko o nā nanoflakes Nb-MXene. ʻO ke ʻano kēia, ma nā wahi a pau e loaʻa ai nā wahi o nā kaomi hapa like ʻole o ka oxygen, ʻo ka wahi me ka pae haʻahaʻa loa e hana i ka anode 80, 81, 82. Maanei, hāʻawi ka microalgae i ka hoʻokumu ʻana o nā cell aerated ʻokoʻa ma ka ʻili o nā flakes MXene, kahi e hana ai i ka oxygen ma muli o ko lākou mau waiwai photosynthetic. ʻO ka hopena, hoʻokumu ʻia nā huahana biocorrosion (i kēia hihia, niobium oxides). ʻO kekahi ʻano ʻē aʻe, hiki i ka microalgae ke hana i nā waikawa organik i hoʻokuʻu ʻia i loko o ka wai83,84. No laila, hoʻokumu ʻia kahi ʻano hoʻouka kaua, no laila e hoʻololi ana i nā Nb-MXenes. Eia kekahi, hiki i ka microalgae ke hoʻololi i ka pH o ke kaiapuni i alkaline ma muli o ka omo ʻana o ke kalapona ʻokikene, hiki ke hana i ka pala79.
ʻOi aku ka mea nui, ʻo ka photoperiod pōʻeleʻele/mālamalama i hoʻohana ʻia i kā mākou noiʻi he mea koʻikoʻi ia no ka hoʻomaopopo ʻana i nā hopena i loaʻa. Ua wehewehe kikoʻī ʻia kēia ʻano ma Djemai-Zoghlache et al. 85 Ua hoʻohana pono lākou i kahi photoperiod 12/12 hola e hōʻike i ka biocorrosion e pili ana me ka biofouling e ka microalgae ʻulaʻula ʻo Porphyridium purpureum. Hōʻike lākou e pili ana ka photoperiod me ka ulu ʻana o ka hiki me ka ʻole o ka biocorrosion, e hōʻike ana iā ia iho ma ke ʻano he pseudoperiodic oscillations a puni 24:00. Ua hōʻoia ʻia kēia mau nānā ʻana e Dowling et al. 86 Ua hōʻike lākou i nā biofilms photosynthetic o cyanobacteria Anabaena. Hoʻokumu ʻia ka oxygen i hoʻoheheʻe ʻia ma lalo o ka hana a ke kukui, kahi e pili ana me kahi loli a i ʻole nā ​​​​​​fluctuations i ka hiki ke biocorrosion manuahi. Hoʻomaopopo ʻia ke koʻikoʻi o ka photoperiod e ka ʻoiaʻiʻo e hoʻonui ka hiki ke biocorrosion manuahi i ka pae mālamalama a emi iho i ka pae pōʻeleʻele. ʻO kēia ma muli o ka oxygen i hana ʻia e ka microalgae photosynthetic, ka mea e hoʻohuli i ka hopena cathodic ma o ke kaomi hapa i hana ʻia ma kahi kokoke i nā electrodes87.
Eia kekahi, ua hana ʻia ka Fourier transform infrared spectroscopy (FTIR) e ʻike ai inā ua loaʻa kekahi mau loli i loko o ka hoʻohuihui kemika o nā cell microalgae ma hope o ka launa pū ʻana me Nb-MXenes. He paʻakikī kēia mau hopena i loaʻa a hōʻike mākou iā lākou ma SI (Nā Kiʻi S23-S25, me nā hopena o ke kahua MAX a me ML MXenes). I ka pōkole, hāʻawi nā spectra kuhikuhi i loaʻa o ka microalgae iā mākou i ka ʻike koʻikoʻi e pili ana i nā ʻano kemika o kēia mau meaola. Aia kēia mau haʻalulu i hiki ke loaʻa ma nā alapine o 1060 cm-1 (CO), 1540 cm-1, 1640 cm-1 (C=C), 1730 cm-1 (C=O), 2850 cm-1, 2920 cm-1. hoʻokahi. 1 1 (C–H) a me 3280 cm–1 (O–H). No SL Nb-MXenes, ua loaʻa iā mākou kahi pūlima hoʻolōʻihi CH-bond e kūlike me kā mākou noiʻi mua38. Eia nō naʻe, ua ʻike mākou ua nalowale kekahi mau piko hou e pili ana me nā pilina C=C a me CH. Hōʻike kēia e loli iki paha ke ʻano kemika o ka microalgae ma muli o ka launa pū ʻana me SL Nb-MXenes.
I ka noʻonoʻo ʻana i nā loli hiki ke hana ʻia i loko o ka biochemistry o ka microalgae, pono e noʻonoʻo hou ʻia ka hōʻiliʻili ʻana o nā oxides inorganic, e like me ka niobium oxide,59. Pili ia i ka lawe ʻana o nā metala e ka ʻili o ke kelepona, ko lākou lawe ʻana i loko o ka cytoplasm, ko lākou pilina me nā hui carboxyl intracellular, a me ko lākou hōʻiliʻili ʻana i loko o nā microalgae polyphosphosomes20,88,89,90. Eia kekahi, mālama ʻia ka pilina ma waena o ka microalgae a me nā metala e nā hui hana o nā kelepona. No kēia kumu, hilinaʻi pū ka omo ʻana i ka kemika o ka ʻili o ka microalgae, he mea paʻakikī loa9,91. Ma keʻano laulā, e like me ka mea i manaʻo ʻia, ua loli iki ka hoʻohui kemika o ka microalgae ʻōmaʻomaʻo ma muli o ka omo ʻana o ka Nb oxide.
ʻO ka mea hoihoi, ua hoʻohuli ʻia ka pale mua ʻana o ka microalgae i ka hala ʻana o ka manawa. E like me kā mākou i ʻike ai, ua lanakila ka microalgae i ka loli mua o ke kaiapuni a ua hoʻi hope i nā helu ulu maʻamau a ua hoʻonui ʻia. Hōʻike nā haʻawina o ka zeta potential i ke kūpaʻa kiʻekiʻe i ka wā i hoʻokomo ʻia ai i loko o nā media nutrient. No laila, ua mālama ʻia ka pilina o ka ʻili ma waena o nā cell microalgae a me nā nanoflakes Nb-MXene ma o nā hoʻokolohua hōʻemi. I kā mākou loiloi hou aku, hōʻuluʻulu mākou i nā ʻano hana nui e pili ana i kēia ʻano kupaianaha o ka microalgae.
Ua hōʻike ʻia nā nānā ʻana o SEM e pili ana nā microalgae i nā Nb-MXenes. Ma ka hoʻohana ʻana i ka loiloi kiʻi dynamic, ke hōʻoia nei mākou e alakaʻi ana kēia hopena i ka hoʻololi ʻana o nā nanoflakes Nb-MXene ʻelua-dimensional i nā ʻāpana poepoe, no laila e hōʻike ana ua pili ka decomposition o nā nanoflakes me kā lākou oxidation. No ka hoʻāʻo ʻana i kā mākou kuhiakau, ua hana mākou i kahi moʻo o nā haʻawina mea a me biochemical. Ma hope o ka hoʻāʻo ʻana, ua oxidized mālie nā nanoflakes a decomposed i nā huahana NbO a me Nb2O5, ʻaʻole i hoʻoweliweli i ka microalgae ʻōmaʻomaʻo. Ma ka hoʻohana ʻana i ka nānā ʻana o FTIR, ʻaʻole mākou i ʻike i nā loli koʻikoʻi i ka haku mele kemika o ka microalgae i hoʻoulu ʻia i ke alo o nā nanoflakes 2D Nb-MXene. Ma ka noʻonoʻo ʻana i ka hiki ke omo ʻia o ka niobium oxide e ka microalgae, ua hana mākou i kahi loiloi fluorescence X-ray. Hōʻike maopopo kēia mau hopena e hānai ana nā microalgae i aʻo ʻia i nā niobium oxides (NbO a me Nb2O5), ʻaʻole ia he mea ʻawaʻawa i ka microalgae i aʻo ʻia.