Tgp chi Khoa hgc Trucmg Dgi hgc Cin Tha Phdn A: Khoa hgc Tu nhien. Cdng nghe va Moi Iruang: 32 (2014): 120-124
Tap chi Khoa hoc Trudng Dai hoc Can The?
website: sj.ctu.edu.vn
1
TONG HOP HAT NANO SiOi i t T TRO VO T R A U B A N G PHlTONG PHAP KET TUA Nguyin Tri Tuin', Nguydn Hihi Minh Phu^ Ho Ngoc Tri Ta^^ Pham Thi Bich Thio', Nguyen Thi Kim Chi', Ld Van Nhan^ Nguydn Trong Tuan' va Trinh Xuin Anh*
' Khoa Khoa hgc Tu nhiin, Trudng Dgi hgc Cdn Tha
^ Khoa Sir phgm, Trudng Dgi hgc Cdn Tha
^ Khoa Cdng nghe, Trudng Bgi hgc Cdn Tha
^ Vien K^ thudt Hda hgc, Trudng Dgi hgc Bdch Khoa Hd Ngi
^Hgc vien cao hgc Hoa, Khoa Khoa hgc Tu nhien Thdng tin chung:
Ngdy nhdn: 06/12/2013 Ngdy chdp nhdn: 30/06/2014 Title:
Synthesis ofSi02 nanoparticles from rice husk ash by precipitation method
Tdkhoa:
Hgt nana, kit lua. nana oxyt silic, tro vo trdu, vo dfnh hinh
Keywords:
Amorphous, nanoparticles, nanosilica, precipitation, Rice huskash'(RHA)
ABSTRACT
Silica nanoparticles have been successfully prepared from rice husk ash by using precipitation method. Al first, the rice husk ash (RHA) was obtained by annealing at temperatures 500 - lOQPC for 4 hours, then nanosilica particles were extracted by using 3N sodium hydroxide solution followed by precipitating with HCI solution to pH = 6. The obtained product was characterized by X-ray diffraction (XRD), Energy-dispersive X-ray spectrometry (EDS), Fourrier Transformation Infrared (FTIR) to determine the crystal lattice structure, phase and elemental composition. The morphology and grain size of the sample were investigated by field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM). The results showed that the prepared SiOj nanoparicles were amorphous phase with the average she about 15 nm.
TOM T A T
Nhiing hat nano Si02 dugc tong App thdnh cdng tit vd trdu bdng phuang phdp kit tua. Luc ddu, vd trdu dugc nung a nhiet do tu 500 - 700°C trong thdi gian 4 h, thu dugc tro vo trdu. Sau do bot nano Silica dugc tdch chiet tit tro trdu bdng cdch sir dung dung dich NaOH co nong dg 3N vd tiep tuc them dung dich HCI d dd pH = 6 cho den khi dung dich ket lua trdng. Sdn phdm bot nano trin dugc dem do nhiiu xg tia X (XRD), tdn sdc ndng lugng (EDS), quang phd hdng ngogi bien doi Fourier de xdc dinh cdu true mgng, thdnh phdn pha, nguyen to vd mdu dugc dem chup dnh hiin vi diin tu quet (FESEM), dnh hien vi diin tu truyen qua (TEM)xdc dfnh kich thudc hgt, hinh thdi hoc. Ket qud, nhOng hgt nano SiOi chi tgo dugc co pha vo dinh hinh vd kich thudc hgt trung binh khodng 15 nm.
1 GIOlTHI|;U
Hien nay, vat lidu phi phim cua ndng nghiep CO nhung tidm nang, phgm vi iing dyng rdng rii trong thyc tiln nhu xa dira, ram ra, b i mia sd dyng lam chat ddt, phin bon, vit lieu xii ly nude thii, sin xuat dl^n va vd triu duge img dung chi tao 1 ^ cii triu, triu vidn diing cho cac Id hoi cdng nghiep ttiay cho than d i hoac 16 gas cd cdng suit ldn tai cac khu cdng n ^ $ p . Trong nude, nhilu nhi san xuit v i nhi i^hidn ciiu su dung vd triu dd lim
ciii triu, gd, thilt bi lpc nude va lim didn cyc cho pin Lithium-ion. Ngoai ra, vd triu cdn cd kha ning ling dung nhilu vio Uong cae liidi vyc xiy dung vi cdng nghiep nhu chd tao ra ggch, bS tdng sieu nhe (tro vd triu tiiay till khoing 20% xi mang thi sg mang lgi hieu qui rit cao cho bd tdng), vat heu bio dn (each nhiet va chdng chay). Vit lieu nay khi ddt chay tgo ra khi sinh khdi cd thi sin xuit ra di^n, nhiet de siy ndng san. Die biet, silicat Uong tro vd triu cd thd dCing dl ehl tao be tdng, g£u:h be tdng
Tgp chi Khoa hgc TrudngDgi hgc Cdn Tho Phdn A: Khoa hgc Tff nhiin, Cdng nghe vd Mdi Irudng: 32 (2014)^)20-124 sidu nhe khdng nung de sii dung Uong liiih v\ic xiy
dyng. Gach be tdng sieu nhe khdng nung, sau khi ehl tgo cd cac tinh ning uu viet nhu nhe, cich nhiet, cich im tdt, tinh chiu nhiet, khi nang cliiu chin dpng tdt, dl chd tgo, than thien vdi mdi trudng. Do do, vit lieu SiOa kich thudc micro vi nano Uong uo vd Uau dugc tdng hpp va iing dyng lim vit lieu xiy dyn^ l i ddi tupng nghien ciiu dugc quan tim mpt sd it tic gii Uong nude (Le Van Hai et al, 2012; Nguyen Van Tuan et al, 2011) vi rit nhieu d ngoai nude (Thuadaij Nittaya et al, 2008), (Ghosh Rajesh et al. 2013), (Rafiee Ezzat et al, 2013) vi (Kalapathy U. et al, 2000).
Trong bii bao nay, chiing tdi Uinh bay phuang phap ket tua dan giin de tdng hgp nhiing hgt nano Si02 td Uo vd Uau sd dung lim vit lidu xiy dyng.
2 THlTC NGHIEM 2.1 Tong hgp cac hat nano Si02 Vd triu dupe rua sgch, phai khd, dem nung d nhiet dp tir 500''C (mau 1), 600°C (mlu 2) va 700''C (mlu 3) Uong thdi gian 4 h thu dupe Uo triu cd mau Uing xam. Tro triu de nguoi dem ngtiiln mjn hing cdi thiiy tmh v i cin 10 g cho vao cdc thiiy tinh 500 mL, tiep tyc cho vao cdc 100 mL NaOH ndng dp 3N. Tien hanh dun hdn hgp Uen bing miy khuiy tir gia nhiet Uong thdi gian 1 h d nhiet dp --200°C. Trong qui Uinh dun, khuiy, cho thSm nude khd ion vao de giii nguyen thi tich hdn hgp ban diu. Sau kbi dun xong, thdm tijr tir 100 mL nude khd ion vao cdc va tidp tyc khuiy d nhidt do phdng Uong thdi gian khoang 20 phiit dl lam ngudi hdn hpp. Tiln hanh loc dung dich 3 lin bing giiy Ipe, thu dugc dung dich cd miu vang nhgt. Toin bd dun^ djch sau khi Ipe cho vio cdc 500 mL rdi khuiy tir, ddng thdi cho dung dich HCI 2,5N tu td vao cdc den cho din khi dung dich trong cdc cd dd pH !=s6 vi ket tua Uang thi ngimg khuiy. Dung dich kit tlia uing thu dugc quay li tam vdi tdc dp 5500 vdng/phut, trong khoang thdi gian 5 - 1 5 phut, dl tich chiet mlu ra khdi dung dich, sau do nia miu thu dugc bing nude khir ion nhilu lin vi ethanol 2 lin. B$t udt thu dugc sau do dugc siy khd d Uong mdi trudng chan khdng (10"^ •;• 10"^ Torr) khoing 20 h, s ^ phim nhan dugc cudi cimg Ii bdt khd miu uing, miu bdt khd thu dugc la nhung hgt nano SiOz-
2.2 Cac phuong phip khao sSt thyr nghiem c i u tnic pha va thinh phin pha ciia san pham ehl tgo dugc khio sit bang may nhilu xa tia X, Bruker D8 Advance (Cu Ka X = 0,154046 ran), hogt ddng d 40 kV/40 mA. Toe dd quet 0,02° s"', tgi Tmng tim Khoa hpc Vgt lieu, Trudng Dgi hpc
Khoa hgc Tu nhidn, Dgi hpc Qudc gia H i Ndi.
Hinh tiiii hpc va kich tiiudc hat cua mlu bdt dugc xic dinh bing inh hiln vi dien hi qudt phit xg trudng (FESEM-JEOL-7600F, 15 kV-Japan), tai Phdng tiu nghidm Lanopel. vien AIST, Dgi hpc Bich Khoa H i Ndi v i inh hiln vi dien tii UuyIn qua (TEM-JEMIOIO, M=x50 - x600.000. S=3A'', U=40-I00 kV), tgi Phdng vi ciu tnic cua Vien V^
smh Dich tl Trung uong. H i Npi. Phd hdng ngogi Fourier (Nicole 6700- FTIR) dupe do tgi Khoa Khoa hpc Ty^ nhidn, Tmdng Dgi hpc Cin Vaa.
3 KET QUA VA THAO LUAN 3.1 Ti'nh chat cau true
Ket qui ntudu xa tia X ciia miu bpt nano Si02 nlian dupe sau qua trinh tdng hop tu vd Uiu dugc nung d nhiet dp 500"C (dudng I), dOO^C (dudng 2) vi 700°C (dudng 3) dugc Umh biy Udn Hlnb I.
Dya vao Hinh 1, chiing tdi thiy giin dd nhilu xa tia X duge dgc tnmg bdi mdt dinh nhilu xg cd dp rOng ban phd Idn nam d giiia 22° vi 23" (26), chiing td nhiing hgt cd kich thudc nhd va cudng dd yeu cho thiy ring mau gin nhu vd dinh hinh. Dp rpng bin phd ciia nhiing dinh nhilu xg (duong I) (dudng 2) v i (dudng 3) co gii tri gin nhu nhau, khdng thay ddi nhidu lim, cho thiy ring nhiing hgt nano SiOz nhin dugc eiia 3 miu cd kich thudc gin gidng nhau.
Hinh 1: Gian do nhilu xa tia X cua nano SiOi tong hgp tirvo triu nung tir 500-700»C, trong
thdi gian 4h
Dua vio gian dd nhilu xg tia X va cdng tiiuc Debye-Sherrer D = 0,9^^ cosB. vdi X li budc sdng uhieu xa tia X, ^ Ii dp bin rpng cue dai ciia vach uhieu xa cao nhit, 0 Ii gde nhilu xg. Chung tdi ti'nh dugc kich tiiudc eua nano SiO^ cda mlu f 2 vi 3 dugc bidu dien d Bing I. Tir kit qua nay (kin^ n cho tiiij, kich tiiudc nano SiO. e i l n h Z S i ^ tiiay d^i khdng nhilu. Didu niy c h d ^ g T w c h
Tgp chi Khoa hgc Trudng Dgi hgc Cdn Tho Phdn A: Khoa hgc Tu nhien, Cdng nghi vd Mdi trudng: 32 (2014): 120-124 thudc nano Si02 khdng phu thudc vio nhidt dp
nung vd Uiu.
Bang 1: Ki'ch thudc trung binh cna hat nano SiOj dugc tdng hgp b^ng phinrag phip kit tfia
Miu t(dO) P (radian) 2Bm D(nm)
1 500 °C 0,05669 22 -2,5
2 600 «C 0,05233
22 -2,7
3 700 °C 0,05233
23 -2,7 MIU 3 dupe do phd tin sac ning lupng (EDS), kit qui dupe bieu dien Udn HJnh 2. Tii day cho thiy cac nguyen td th^nh phin xu^ hidn Uong miu gdm cac nguydn td nhu Silic (Si), dxy (O) la cac thanh phin ehinh cua cic hat nano SiOj. Ttiinh phin nguydn td oxy chiem ti 1^ phin Uam upng lupng (57%) ldn hon Silic (43%) Uong mau. Cac nguyen td cd Uong phd EDS ddng nhu cac thinh p h ^ dS dua vao trong qua Uinli tong hpp.
Hinh 2: Gian do pho tan s9c ning lugng eua cac hgt nano SiOi
Anh hiln vi dien td qudt eia mlu bdt nano Si02
dupe tach chilt tii vd triu dugc nung d nhiet dp 500°C trong tiidi gian 4 h (mau I) bilu diln d hmh 3, Kich tiiudc trung binh eua cac hgt nano SiOj nay khoang 10 nm, Idn ban tdch tiiudc dugc ti'nh bing cdng thiie Debye-Sherrer la ~3 nm. Kit qui do dugc khdng phii hgp vdi kich thudc hgt dugc ti'nh toin dua Uen giin dd nhilu xa tia X nhu di trinh biy d Udn, li do kich thudc tmh trdn inh FESEM li kich thudc hgt, cdn kich thudc dua tren gian dd nhidu xa tia X li kfch thudc tinh thd.
. ^ » ^ ^ : -
Hinh 3: Anh FESEM ciia nhihig hgt nano SiOj dugc nung if SOO^C, trong thdi gian 4 h Hinh 4a ii inh FESEM eua mlu bdt nano SiOi dugc chd tao bang phuoi^ phap ket tiia tir vd triu dugc nung d nhi^t dd 600 "C (mlu 2) vi d ntiiet dp 700 °C (mlu 3) trong thai ^an 4 h, Hinh thai hpc ciia nhimg hgt nano SiOz cua hai mau Udn diu c6 d ^ g hgt, kieh thudc trung binh gin nhu nhau, khoang 1 0 - 1 5 run, ton ban mdt chit so vdi kich thudc hat ciia mlu 1 va dudng nhu cic hgt ket dim tgi nhau cho nen thay.nhiJng dam hat cd dang xop.
Hinh 4: Anh FESEM cua nh&ng hgt nano SiOi duge nung d eOO^C (a) vi 700''C, trong thdi gian 4 h
Tgp chi Khoa hgc Trudng Dgi hgc Cdn Tho Phdn A: Khoa hgc Tunhiin. Cdng nghi vd Mdi trudng: 32 (2014)^^20-124 Anh hiln vi dien tu truydn qua ciia miu bdt
nano SiOi nung d nhiet do 500"C, Uong thdi gian 4 h, dupe md t i d Hinh 5. Kit qua, chiing tdi thiy ldch tiiudc hat trung bmh khoang 10 nm, khdng ddng ddu ntiau, tuang dug vdi kdt qua ldch thudc hat ciia mau do anb FESEM d Uen Hinh 3, hinh nhu cic hgt kit ty lai vdi nhau hinh thanh nen nhimg dam hgt
t Mag^ ItTODOX fl
Hinh 5: Anh TEM cua nhftng hat nano SiOi dugc nung d uhi^t dp SOO°C, trong thdi gian 4 h
Hinh 6: Anh TEM ciia nhihig hgt nano SiOi dugc nung d 600 •€ (a) v i 700 °C (b), trong thdi
gian 4 h
Hinh 6 la inh TEM eiia miu bpt nano SiOj duge nung d nhidt dp 600 "C (a) va 700 ^ (b) tixmg tiidi gian 4 h, kich thudc hgt cua hai mau tidn gin gidng nhau, khoing 10-20 nm tuong dng vdi kich thudc hgt cua nhung mlu tren d Hinh 4.
Nhihig hat nano sihea niy cd xu hudng ket tu lgi vdi nhau tao thinh mpt dim hgt cd dgng xdp.
3.2 Phd hdng ngogi Fourier (FTIR) Phd hdng ngogi cua hat nano SACh dugc tich chilt hi vd uiu dugc nung d 500,600 "C v i Uo ciia vd triu dugc nung 600 °C frong thdi gian 4 h dugc trinh biy d Hinh 7. Kit qui, phd FTIR cho tiiiy nhihig hgt nano silica (Hinh 7a,b) v i Uo ciia vd triu (Hmh 7c) ddu ed dinh phd tgi sd sdng 801 v i 1100 cm"' la do mode ddi xiing vi bat ddi xdng cda lien kit Si-O-Si.
500 1000 1500 2000 2500 3000 3500 So s6ng <Cm'')
Hinh 7: Phd FTIR cua nhung hat nano Si02 dugc nung d SOO, 600°C va tro t r i u nung 600"C,
trong 4 h
Dinh phd cd tim tai 469 cm'' Ii do mode udn ciia Si-O-Si, va dmh phd ed sd sdng tgi 3456 em"' li do sy hien didn dao dpng kdo din nhdm O-H eua nhdm silanol dl duy Ui sy hip tiiy nude. Vung phd cd sd sdng 1640 cm"' Ii do dao ddng udn ciia phan tii nude (O-H) bao quanh ma Uin silica (Le Van Hai et al, 2013; Rafiee Ezzat et al., 2012). Dmh ed sd sdng tgi 2365 cm"' dao d^ng cua P-H cua axit photphoric CO Uong mlu, khdng c6 dmh nio tim tiiiy d giiia so sdng 2,500 vi 3000 em"', chdng to la Ididng cd hgp chit gdc hihi co trong bdt silica (Rafiee Ezzat et al, 2012), Mpt tin n i ^ cho tiiiy nhimg hgt nano silica tong hpp dupe ed Uang tiiii
vo dinh hinh. ' 4 KET LUAN
Ching tdi da ehl tao dupe cac hat nano SiO^
bing pliucmg p b ^ ket tiia tir vd uiu duac nmifi d nhiet dp 500 - 700 ''C. Cie kit qua phin t i c T j a ^
r<ip chi Khoa hgc TrudngDgi hgc Cdn Tha Phdn A: Khoa hgc Tu nhien. Cdng nghi vd Mdi Irudng: 32 (2014): 120-124 dd nhieu xg tia X, FTIR cho thiy cic hat nano SiO;
ddu ed cau tnic pha vd dinh hinh. Nhimg hgt nano SiO: cd hinh thai dang hat v i kich thudc trung binh
~ 15 nm. Nhfhig hat nano Uen kit tu Igi thinh nhihig dam hgt cd kich thudc ldn ban v i cd dgng xdp, do nd tinh chit xdp va didn tich be mat rieng Idn cho ndn cd khi nang u i ^ dung trong tmh vy:e vgt !i?u xiy dyng, die bidt la ggch bd tong nh?
khdng nung.
LOfI CAM TA
NghiSn cim Udn dupe tii trg bdi quj nghidn cdu khoa hpc co ban cip Trudng Dgi hpc Can Tho, dltaimasdT2013-20.
T A I L I E U THAM KHAO
1. Ghosh Rajesh and Bhattacherjee Sounak, 2013. A Review Smdy on Precipitated Silica and Activated Carbon from Rice Husk. J Chem Eng Process Tectmol. 4:4.
2. Kalapatiiy U, et al, 2000. A sunple metiiod for production of pure silica from rice hull ash. Bioresource Technology, 73:257-262.
Le Van Hai et al, 2013. Syntiiesis of silica nanoparticles from Viemaraese rice husk by sot-get metiiod. Nanoscale Research Letters. 8:58.
Nguyen Van Tuan et al, 2011. Hydration and microstmeture of ultra high performance concrete hicorporating rice husk ash. Cement and Concrete Research.
41:1104-1111.
Nguyen Van Tuan et al, 2011. TTie smdy of using rice husk ash to produce ultra high performance concrete. ConsUuction and Building Materials. 25: 2030-2035, Rafiee Ezzat et al 2012. Optimization of synthesis and characterization of nanosilica produced from rice husk (a common waste material). Intemational Nano Letters. 2:29.
Thuadaij Nittaya and Nuntiya Apinon, 2008. Preparation of Nanosilica Powder from Rice Husk Ash by Precipitation Metiiod. Chiang Mai J. Sei. 35(1) : 206-211,
