Preparation of with a Hollow Olive-shaped Cable by Electrospinning

Transcription

1 109 A puliction of CHEMICAL ENGINEERING TRANSACTIONS VOL. 60, 2017 Guest Editors: Luc Di Plm, Elisett Petrucci, Mrco Stoller Copyright 2017, AIDIC Servizi S.r.l. ISBN ; ISSN The Itlin Assocition of Chemicl Engineering Online t DOI: /CET Preprtion of TiO2@SiO2 with Hollow Olive-shped Cle y Electrospinning Qin Feng, Lei Wng*, Liye Su, Shuzhi Xu North Chin University of Science nd Technology, Tngshn , Chin School of Grin, Jilin Business nd Technology College, Chngchun130507, Chin wdl8898@yeh.net The TiO2@SiO2 coxil hollow olive-shped cle hs een prepred y using the three-lyer coxil electrospinning technique. This technique lso cn e used to prepre the coxil olive-shped cle of other inorgnic sustnces. In this pper the smples were chrcterized dopting mny-wys such s differentil therml nlysis (TG-DTA) nd X-ry diffrctometry (XRD), infrred spectrogrph (FTIR), scnning electron microscopy (SEM), trnsmission electron microscopy (TEM) nd energy dispersive spectrometer (EDS) techniques. XRD nlysis nd FTIR nlysis show tht the coxil hollow olive-shped cle otined t 600 hs n inner wll of crystlline TiO2 nd n outer wll of morphous SiO2. SEM nlysis nd TEM nlysis show tht the coxil hollow olive-shped cle is formed fter sintering t 600. Its middle dimeter is out 1.4um, the terminl dimeter is out 210nm, the thickness of the inner wll is out 200nm, the shell thickness is out 100nm nd the length of the shell is out 5um. However, fter sintering t 800, the oliveshped hollow tue collpses. EDS nlysis shows tht the sintered smples minly contin three elements which re O, Si nd Ti. The formtion mechnism of the TiO2@SiO2 hollow olive-shped cles is preliminrily investigted. 1. Introduction One-dimensionl nnomterils, such s nnowires, nnotues, nnoelts nd nnocles, hve een successfully synthesized y mny methods. In recent yers, reserchers hve pid gret ttention to the synthesis of multilyer coxil composite nnomterils. For exmple, DG Shin nd others synthesized the MoS2/CNT coxil nnotue y using hydrotherml method (Shin, et l., 2015); Hu nd others comined the therml precipittion nd physicl evportion to synthesize three-lyer coxil nnocles (G/G2O3/ZnO) nd the G2O3/ZnO two-lyer coxil nnotues (Hu, et l., 2014); for the composite mteril of onedimensionl TiO2 /SiO2 nno-structured mterils, Zhng nd others prepred the coxil TiO2/SiO2 nnotues y using the sol-gel nd gs method; Xu nd others prepred the TiO2/SiO2 composite hollow nnofires, TiO2@SiO2 sumicron coxil cles nd TiO2@SiO2 coxil doule-wll sumicron y using electrospinning technology (Xu, et l., 2012). In this pper, electrosttic spinning is crried out y replcing single nozzle with three-lyer coxil nozzles, nd fter one step, TiO2@SiO2 hollow olive-shped cles re prepred directly. The smples re chrcterized y using modern nlyticl techniques, nd their formtion mechnism is nlyzed, thus, some meningful results re otined. 2. Experimentl 2.1 Preprtion of precursor solution A certin mount of polyvinylpyrrolidone (PVP, verge moleculr weight is , AR) is dded to the mixed solution of the pproprite mount of nhydrous ethnol (C2H5OH,AR) nd chloroform (CHCl3, AR). After mgnetic stirring t room temperture for 3h, certin mount of ethyl orthosilicte [(C2H5O) 4Si,AR] is dded to it, nd then it continues to e mgneticlly stirred for 6h. After tht, it should sty for 3h nd then Plese cite this rticle s: Feng Q., Wng L., Su L., Xu S., 2017, Preprtion of tio2@sio2 with hollow olive-shped cle y electrospinning, Chemicl Engineering Trnsctions, 60, DOI: /CET

2 110 the outer spinning solution [PVP +(C2H5O) 4Si + C2H5OH + CHCl3] cn e otined. The mss frction of PVP, (C2H5O) 4Si, C2H5OH nd CHCl3 is respectively the 8.0%, 14.7%, 61.7% nd 15.6%. After the mixed solution(volume rtio is 1:1) of sesme oil nd soritn olete(spn-80 emulgtor) is stirred t room temperture for 3h, the utyl titnte with equl volume is dded to it, nd then it continues to e stirred for 6h. After tht, it should sty for 3h nd then the interlyer spinning solution [Sesme oil+spn-80+ Ti(OC4H9)4] cn e otined. The mss frction of utyl titnte, sesme oil nd soritn olete is respectively the 50.1%, 23.9% nd 26.0%. 2.2 The preprtion of [Sesme oil+spn-80+ Ti(OC4H9)4]@ [PVP+(C2H5O) 4Si] coxil hollow composite fier Three-lyer coxil electrosttic spinning device is shown in Figure 1. The three-lyer coxil nozzle is composed of three stinless steel tues tht ll nest inside one nother, nd the inner dimeters of the inner, middle nd outer nozzles re respectively the 0.7mm,1.2 mm nd1.8 mm. The inner nozzle is out 0.5mm shorter thn the middle nozzle, nd lso the middle nozzle is out 0.5mm shorter thn the outer nozzle. Ech spry tue is respectively connected with the inner, middle nd externl liquid storge continers. Mke sure the spry tues re coxil nd the gp cn flow smoothly out of the solution. The prepred [PVP +(C2H5O) 4Si + C2H5OH + CHCl3] solution, s the outer solution, is plced in the externl liquid storge continer. The [Sesme oil+spn-80+ Ti(OC4H9)4] solution, s the intermedite solution is plced in the middle liquid storge continer. The inner liquid storge continer is connected with the tmosphere. The DC positive electric field is directly dded to the outer lyer nd the intermedite lyer solution, nd the spinning formed [Sesme oil+spn-80+ti(oc4h9)4]@ [PVP+(C2H5O) 4Si] coxil composite fiers re received y the luminum foil which connects with the negtive electrode. In the experiment, the distnce etween the nozzle nd the receiving screen is 12cm, the pplied voltge is 7.0kV, the mient temperture is 18-20, nd the environmentl humidity is 40%-45%. Figure 1: Setup of the multilyer coxil electrospinning 2.3 The preprtion of the TiO2@SiO2 hollow olive-shped cle The prepred [Sesme oil+spn-80+ Ti(OC4H9)4]@ [PVP+(C2H5O) 4Si] coxil composite fiers re rosted through the progrmmed temperture control furnce, nd the heting rte is 1 /min. When the temperture is 600 nd 800, fter keeping the constnt temperture for 10 h, the temperture should e reduced to the room temperture t the sme rte, nd then the TiO2@SiO2 hollow olive-shped cle cn e otined. 2.4 Chrcteriztion method Y-2000 X-ry diffrctometer produced y Shengd Ry Instrument Co., Ltd is used to mke the structurl nlysis. Cu trget Kα rdition is used, Ni is tken s the filter, the scnning speed is 3 /min, step size is 0.04, working current is 20 ma nd voltge is 40kV. The XL-30 field emission environment scnning electron microscope of Netherlnds PHILIPS Compny is used to nlyze the dimeter nd morphology of the fier. JEM-2010 trnsmission electron microscope of Jpnese JEOL Compny is used to nlyze the fier

3 structure. OXFORD ISIS-300 X-ry energy dispersive spectrometer is used to mke the elementl nlysis. The FTIR8400S FTIR spectrometer of Jpnese Shimdzu Compny is used to mke the FTIR nlysis of the smple. KBr sqush technique is used nd the wve-numer rnge is cm Results nd discussion 3.1 XRD Anlysis Figure 2 is the XRD digrm of the smple fter the sintering of the composite fier for 10 h t 600 () nd 800 (). We cn see tht with the increse of sintering temperture, the orgnic mtter is grdully oxidized nd decomposed, nd lso voltilizes from Figure 2(). And the rod morphous dispersion pek ppers, which is minly the diffrction pek of morphous SiO2. When 2θ= (101), (103), (004), (112) nd (200), the wek diffrction peks of ntse TiO2 pper. Their d vlue nd the reltive intensities re siclly the sme s the d vlue nd reltive intensities listed in PDF crd ( ) of TiO2. At the sme time, when 2θ= (110), (101), (211) nd (220), the wek diffrction peks of rutile TiO2 pper, indicting tht TiO2 is the mixed crystl crystlline form of ntse nd rutile t 600. When the sintering temperture reches 800, from the Figure 2(), we cn see tht the rod morphous dispersion pek round 2θ = 22 is minly the diffrction pek of morphous SiO2. The diffrction pek of ntse TiO2 wekens, ut the chrcteristic diffrction pek of the rutile crystl fce strengthens. When 2θ= (111) nd (301), the chrcteristic diffrction peks of the rutile TiO2 lso pper. Their d vlue nd the reltive intensities re siclly the sme s the d vlue nd reltive intensities listed in PDF crd ( ) of TiO2, indicting tht when the temperture is 800, TiO2 is minly the rutile TiO2. The ntse TiO2 nd rutile TiO2 oth elong to the tetrgonl system, nd the spce group is P42/mnm. Becuse of the cldding of shell SiO2 nd the influence of onding etween them, the intensity of diffrction pek of TiO2 is oviously wekened. 111 Intensity/.u θ/ ( 0 ) (220) (301) (111) (211) (101) (101) (004) (112) (110) (110) (103) (101) (211) (200) Figure 2: XRD ptterns of the smple clcined t ) 600 nd ) 800 for 10 h 3.2 SEM Anlysis RuAntitlesTiOTi2eThe SEM photos of smple re shown in Figure 3. We cn see tht t different clcintion tempertures, the morphology of the smple is significntly different. From Figure 3() nd 3(), we cn see tht when sintering temperture is 600, the uniform hollow olive-shped cles re minly formed, nd menwhile some nnotues re formed. The smples hve the uniform ppernce, smooth surfce nd no cohesiveness, nd hve good dispersiility. From the cross section of the smple in the figure, we cn see tht it presents the ovious hollow structure, the middle dimeter of the olive-shped hollow tue is etween nm, the terminl dimeter of the olive-shped hollow tue is etween nm nd the length is etween 4-8um. Due to the different frcture position of the fiers, t the sme time some nnotues re formed. The dimeter of the nnotues is etween nm nd the length is etween 2-6um. From the Figure 3(c) nd 3(d), we cn see tht with the increse of sintering temperture, when the sintering temperture is 800, the oliveshped hollow tue collpses ecuse the wll of the formed hollow tue is thin, the volume of the hollow prt increses nd the surfce tension of the tue is not enough to support the hollow structure of the tue. O2

4 112 1μm 10μm d c 20μm 5μm Figure 3: SEM imges of smples t -) 600 nd c-d) nm 500nm 500nm d c 1um Figure 4: TEM imges of smples t nm

5 TEM Anlysis TEM is used to further mke the structurl nlysis. The trnsmission electron microscope imges of the smples when the sintering temperture is 600 re shown in Figure 4, nd the olive-shped hollow tue is formed. Figure 4() is TEM photo of single olive-shped hollow tue with good coxility nd uniform rdil distriution. The middle dimeter of the olive-shped hollow tue is out 1.4 um nd the terminl dimeter is out 210nm. The figure 4() illustrtion is the locl high resolution TEM photo. The light color of the contrst of the core shows tht the core is hollow. Due to differences in property nd the structure of the mtrix mteril, the tue wll presents the ovious strtifiction, which shows tht the inner wll of the tue nd the shell hve different chemicl compositions, nd the olive-shped hollow tue is multi-wlled structure. The thickness of the inner wll is out 200nm, the thickness of the shell is out 100nm nd the length is out 5um. Figure 4(d) is the TEM photo of the tuulr portion. It is the hollow structure, the tue wll is oviously strtified nd typicl multi-wlled nnotue is formed. The dimeter of the nnotue is out 600nm, the dimeter of the hollow prt of the core is out 300nm, nd the thickness of the inner wll of the tue nd the shell is out 75nm. The floccultion mteril on the fier surfce is morphous SiO2, nd the prticles re crystllinetio2 prticles. 3.4 FTIR nlysis Figure 5 is the infrred spectrogrm of the smple fter sintering to 600 () nd 800 (). Trnsmittnce/% Wvenumer/cm -1 Figure 5: FTIR spectr of the smples t ) 600 nd ) 800 According to the figure, we cn see tht fter sintering to 600 nd 800, the spectrogrms were siclly the sme, indicting tht the smple gets the pure inorgnic ingredients. From figure 5 (), we cn see tht sorption pek t 952 cm-1 is cused y the virtion of Si-O-Ti ond, which shows tht the new chemicl onds re formed mong Ti, O nd Si. The sorption peks t 806cm-1 nd 463cm-1 re the ending virtion sorption of Si-O-Si ond. The intensity of the virtion sorption pek of Ti-O ond t 623cm-1 is wek, which is minly cused y the cldding of the shell SiO2. The sorption peks t 1091cm-1 nd 806cm-1 re the virtions of the Si-O ond. The hydroxyl sorption pek t 3448cm-1 is reltively shrp, indicting tht the surfce of it contins lrge numer of Si-OH rdicl groups. The hydroxyl ssocition sorption pek t 1655cm-1 shows tht there is strong dsorption etween fiers. 3.5 EDS nlysis In order to further determine the composition of the generted olive-shped cle, the EDS nlysis hs een mde for the smple (800 ), s shown in Figure 6. We cn oserve the spectrl pek of the O, Si nd Ti (Au nd C come from the metl sprying of the smple surfce efore test, nd the smple s doule fced dhesive tpe or underfiring residue efore the test), which shows tht the smple contins three kinds of elements which re O, Si nd Ti.

6 114 Si Intensity/.u. O Ti C Au Ti Ti Energy(Kev) Figure 6: EDS surfce nlysis of smples clcined t Conclusions TiO2@SiO2 hollow olive-shped cles were successfully synthesized y coxil electrospinning technique using tetrutyl titnte, tetrethyl orthosilicte, polyvinyl pyrrolidone, solute ethnol, sesme oil, spn-80 nd chloroform s strting mterils. The synthetic steps re few nd the conditions re esy to control. The results indicted tht the products re TiO2@SiO2 hollow olive-shped cles with n morphous SiO2 outer shell, crystlline TiO2 inwll. The hollow olive-shped cles possess thickness of inwll of c. 200 nm nd outer shell of c. 100 nm, medi-dimeter of c. 1.4 um, erminl dimeter of c. 210 nm, length of c. 5 um. Acknowledgments This work is supported y the Science nd Technology Progrm Project of Heei Province (No ). Reference Hu T., LQ Ye, WL Li, JH Luo, B Jing, 2014, Preprtion nd chrcteriztion of TiO2-SiO2/TiO2 two-lyer ntireflective coting photo-ctlyst, Chinese Journl of Inorgnic Chemistry, 30(8), Shin DG, EJ Jin, YJ Lee, WT Kwon, Y Kim, 2015, TiO2-SiO2 Nnocomposite Fiers Prepred y Electrospinning of Ti-PCS Mixed Solution, Koren Chemicl Engineering Reserch, 53(3), Xu Sz, XT Dong, GQ Gi, JX Wng, GX Liu, TX Lu, 2012, Preprtion of TiO2@SiO2 coxil doule-wlled sumicrotues y trifluidic coxil electrospinning nd its photoctlytic property, Act Chimic Sinic, 70(15) : Zhng Sh, XT Dong, SZ Xu, JX Wng, 2008, Preprtion nd chrcteriztion of TiO2/SiO2 composite hollow nnofires vi n electrospinning technique, Act Mterie Composite Sinic, 25 (3):