Electrospun nanowire arrays for electronics and optoelectronics

Transcription

1 mter.sihin.om link.springer.om SCIENCE CHINA Mterils Pulishe online 3 Mrh 216 oi: 1.17/s Si Chin Mter 216, 59(3): SPECIAL ISSUE: Emerging Investigtors of Nnomterils Eletrospun nnowire rrys for eletronis n optoeletronis Zhi Zheng, Lin Gn n Tinyou Zhi * ABSTRACT Alignment of NWs (NWs) is the ore issue for integrting NWs into nnoevies in future. This review me onise retrospet on reporte ssemling methos n minly emphsize on the eletrospinning metho n its evelopments, s well s the following pplitions of the ligne nnowire rry (NWA) in eletronis n optoeletronis. First, we lssifie reporte ssemling methos into three tegories: grow then ple, ple then grow n grow n ple (eletrospinning metho). Then, we fouse on the eletrospinning metho n its moifie metho inluing fiel ssiste metho, rotting olletor ssiste metho n ner-fiel ssiste methos, s well s their merits n efets, respetively. Next, we illustrte the pplitions of the NWs rrys frite y eletrospinning in fiel effet trnsistors (FET), gs sensors, piezoeletri sensors n photoetetors. Finlly, we me short onlusion n prospetion on eletrospinning metho. As n esy n hep nnowire frition n lignment metho, eletrospinning hs right future in one-imensionl mterils se eletronis n optoeletronis. Eletrospinning is hep n stle tehnique tht llows the frition of ontinuous n uniform fiers, either orgni or inorgni, with imeters rnging from tens of nnometers to severl mirometers for mss proution [5 7]. Moreover, highly orere ligne nnowire rry (NWA) n lso e esily hieve on vrious sustrtes se on moifie eletrospinning, whih is gretly enefiil to the following pplitions of NWs in vrious fiels shown in Fig. 1. In this review, we provie onise retrospetion on the ssemling methos n primrily highlight the eletrospinning metho n orresponing pplitions of NWA inluing eletroes, fiel effet trnsistors (FET), piezoeletri sensor, gs sensor, n photoetetors. We lso give omments n prospetion in the Keywors: eletrospinning, ligne nnowire rry, eletronis, optoeletronis INTRODUCTION One-imensionl (1D) semionutor nnowires (NWs) re iel uiling loks for nno-iruit not only euse of their unique eletril n optil properties [1 3], ut lso for their omptiility to e oth onuting hnnel n onneting wires in the iruit. With the rpi evelopment of eletronis n optoeletronis, the requirements on the minituriztion n funtionliztion of evies motivte fst growing reserhes in regring to nnostrutures frition n lignment [4]. Furthermore, the improving integrtion ensity of nno-iruit requests highly orere rrngement for trgeting nnostrutures. Therefore, the lignment methos use to frite nnostrutures re signifint. Figure 1 Applitions of NWA in trnsprent eletroes, FET, gs sensor, photoetetor n flexile isplys. Stte Key Lortory of Mteril Proessing n Die & Moul Tehnology, Shool of Mterils Siene n Engineering, Huzhong University of Siene n Tehnology (HUST), Wuhn 4374, Chin * Corresponing uthor (emil: zhity@hust.eu.n) 2 Mrh 216 Vol.59 No.3

2 SCIENCE CHINA Mterils REVIEWS finl setion on the future evelopment of eletrospinning metho. METHODS TO ASSEMBLE NWs Generlly there re two moes of NWs ssemly, tht is, vertil n horizontl ssemlies. However, for the vertil NWs ssemly methos, mny exellent review ppers hve me omprehensively summries on it [8 1], thus in this review, we exlusively onentrte on horizontl ssemly methos. Moreover, there is lmost no restrition on the hoie of sustrtes n epositing lyer numers n ngles of NWs for horizontl sse mly [11,12], whih lso mke suh n rry moe importnt. In this review, we further lssify ll horizontl ssemling into three kins: grow then ple, ple then grow n grow n ple, nmely, eletrospinning metho s shown in Fig. 2. Grow then ple metho As-synthesize NWs usully re rnomly istriute [13 17]. To lign those messy NWs, mny strtegies hve een propose, for instne, eletri/mgneti-fiel, ontt/roll printing tehniques, eletrostti intertion, Lngmuir-Blogett (LB), ule-lown tehniques, s shown in Fig. 3. In this setion, we riefly introue severl importnt pprohes [18]. As vivily reporte y Yng et l. [19], LB is tehnique tht trnsfer nnomterils onto trgeting sustrte s form of monolyer (LB film) with high egree of struture orer s shown in Fig. 3 [2]. This tehnique hs een lso extene to other 1D NWs suh s Ag NWs [21], Ge NWs [22], V 2 O 5 NWs [23], ZnSe NWs [24], PS NWs n BCrO 4 nnoros [25,26]. However, surftnts re neessry for this tehnique to moify the surfe of NWs n prevent the ggregtion of NWs. Blown ule metho is nother metho to prepre ensity ontrolle n wellligne NW pttern [27]. Generlly, the ligne nnomterils exist s free stning films tht n e trnsferre onto vrious sustrtes suh s rigi, flexile n urve sustrtes (Fig. 3) [11]. But the neessry shple mtrix is iffiult to remove fter lignment. Diret intertions etween the NWs n the ptterne surfes n lso e utilize to seletively lign NWs [28,29]. Usully, the NWs exhiit strong ffinity to polr self-ssemle monolyer ptterns, for exmple, single wll ron nnotues (SWCNTs) show strong ffinity to most re surfes (Au, Si, Al, SiO 2, n glss) (Fig. 3) [3]. The rwk of this tehnique is tht the lignment qulity of NWs is low. Contt printing is metho tht n operte in non-liqui environment [31 34]. Briefly speking, this tehnique n trnsfer NWs from growth sustrte to reeiver sustrte with the help of iretionl sher fore s shown in Fig. 3 [33]. During this proess, the ens of NWs stik to the reeiver sustrte y the vn er Wls intertions, n the remining length is ligne y the pulling fore. This metho is fit to vrious mterils, inluing Zn 3 As 2 [35], X(In, G)P [36], Ge [37], Si [38], SWCNTs [39]. However, requirements tht mterils shoul typilly grow vertilly on the sustrte my limit its pplition. Fiel ssiste methos lign NWs normlly using the ieletrophoresis (DEP) or mgneti fiel [4,41]. This lignment mehnism n e lerly illustrte in Fig. 3e. The existe hrge neutrl regions in the pn Si NWs will e polrize when expose to iret urrent eletri fiel. Then the DEP fores will ttrt the pn Si NWs to the eletroe eges, on the other sie, NWs will e juste to prllel to eh other. The rwk of this metho is tht prefrite miroeletroe rrys re neee n reorienttion n ggregtion of the NWs will our if solvent is evporte [42]. Ple then grow metho The grow then ple metho n lign NWs n ontrol V+ V Silion oxie V Figure 2 Shemti illustrtion of methos for ssemling NWs. () Grow then ple metho. () Grow n ple, nmely, eletrospinning metho. () Ple then grow metho. Mrh 216 Vol.59 No.3 21

3 SCIENCE CHINA Mterils F (i) (ii) (iii) P Growth sustrte (flip over) e F EP F EP F DEP F DEP + Trnsfre sustrte Anhoring region Growth sustrte Trnsfer sustrte Coming region V SiO 2 Figure 3 Typil methos of grow then ple strtegy. () Assemling y LB metho. Reprinte with permission from Ref. [2] (Copyright 23, Amerin Chemil Soiety). () Assemling y lown ule metho. Reprinte with permission from Ref. [11] (Copyright 27, Nture Pulishing Group). () Assemling y moleulr inter-tomi fores. Reprinte with permission from Ref. [3] (Copyright 23, Nture Pulishing Group). () Assemling NWs y mehnil sher fores. Reprinte with permission from Ref. [33] (Copyright 213, Nture Pulishing Group). (e) Assemling NWs y eletri fiel fore. Reprinte with permission from Ref. [42] (Copyright 21, Amerin Chemil Soiety). the lotions in some egree. However, the ple proessing is rrie out in trnsfer mei n NWs shoul e moifie with funtionl group whih my influene the surfe lenness of the NWs n the evie performne. Reently, ple then grow strtegy ws investigte y reserhers. This tehnique refers to grow ligne NWs on speifi lotions n tke preetermine orienttion with one step. A retive wy is utilizing the growth of lterlly oriente Si NWs etween vertil (111) Si plnes vi ething (11)-oriente Si wfer s shown in Fig. 4 [43]. This is file wy to onstrut eletroni evies in nno sle. However, NW speies, ensity n numers re not esy to ontrol. An esier wy s shown in Fig. 4 is to sputter the Au p using metl msk on qurtz sustrte. Li et l. [44] grow the ZnO sule nnoriges whih hve high sensitivity n fst response to the UV light. Controllle plnr <11> GAs NW rry on GAs (1) sustrtes n e otine t higher growth temperture (>45 C) s shown in Fig. 4. Diretion of growth etween the NWs n plnr n e juste y growth temperture [45]. Further, Tsivion et l. [46] n urtely ontrol the growth morphology n rystllogrphi orienttion vi vpor-liq ui-soli (VLS) growth moe. The growth moe whih eies the growth morphology hs lose reltionship to the sustrtes symmetry s follows: () growth long speifi lttie iretions, () grphoepitxil growth long nnosteps, () grphoepitxil growth long nnogrooves. This strtegy is lso fit to other inorgni NWs suh s GN (Fig. 4). However, it is iffiult to otin the sustrte with ifferent orienttions to guie the growth. A onfinement-guie growth metho ws opte y Pevzner et l. [47] to preesign the synthesize NWs oth in the hemil n physil ttriutes n the geometry s illustrte in Fig. 4e. This tehnique n exten to vrious sustrtes suh s silion wfer, qurtz n glss slies, n even plsti sustrtes [47]. Moreover, in-plne epitxy metho hs importnt pplitions in friting the p-n juntions [48]. For exmple, Yu et l. [48] reporte this strtegy to grow p-si NWs rrys on n-si(1) sustrtes y plsm enhne hemil vpor eposition (PECVD) (Fig. 4f). Aove ll, the ple then grow pprohes hve etter effet on lignment of NWs euse the rrys re preesigne efore NWs growth, in ontrst with the grow then ple strtegy. However, this lignment my e limite to speifi mterils n sustrtes, suh s Si NWs on (111) sustrte of silion. So iret n muh more universl ssemling strtegy shoul e explore. 22 Mrh 216 Vol.59 No.3

4 SCIENCE CHINA Mterils REVIEWS ZnO sule NB ZnO NW lver e f Figure 4 Shemti igrm of ple then grow strtegy. () Silion nnoriges forme etween two vertil silion surfes. Reprinte with permission from Ref. [43] (Copyright 24, IOP Pulishing Lt.). () Brige growth pttern of the ZnO sule. Reprinte with permission from Ref. [39] (Copyright 21, IOP Pulishing Lt). () GAs NWs on GAs (1) sustrtes. Reprinte with permission from Ref. [4] (Copyright 28, Amerin Chemil Soiety). () ZnO sule nnoriges self-ssemle in the gp. Reprinte with permission from Ref. [41] (Copyright 212, Amerin Chemil Soiety). (e) Confinement-guie shping growth of silion NWs. Reprinte with permission from Ref. [42] (Copyright 212, Amerin Chemil Soiety). (f) In-plne epitxil growth of silion NWs. Reprinte with permission from Ref. [43] (Copyright 214, Amerin Chemil Soiety). Grow n ple eletrospinning metho Eletrospinning is low ost n verstile strtegy for friting NWs inluing orgni n inorgni NWs [49]. Stle n rpi proution proess mkes it one promising tehnique tht meets the requirements of mss proution. The priniple of eletrospinning is similr to the eletrospry proess [5]. The preursor liqui forms Tylor one uring the eletrospinning proess t first n then turns into hrge jet uner high eletrostti voltge. The hrge jet will e further elongte n thinne seprtely uner eletrostti fore n Coulom repulsion uring trvelling from outlet of injetor to olletor. However, the rnom orienttions of the NWs my limit the pplition in eletronis n optoeletronis. To voi the messy olletion of NWs, some moifitions on eletrospinning hve een propose s shown in Fig. 5. In the following prt, we will give n introution to suh moifitions inluing fiel ssiste metho [51 53], rotting olletor ssiste m etho [54 56] n ner-fiel ssiste metho, et. With the evelopment of these improve tehniques, eletrospinning eomes metho tht n onut NWs growth n lignment simultneously. Fiel ssiste metho In ontrst to n integrte olleting eletroe pplie in onventionl eletrospinning metho, well ligne NWs n e otine y using two seprte onutive sustrtes s the olletor. The preursor NWs re highly positively hrge uner high voltge, n the sustrte is negtively hrge. The movement of the NWs is influene y two types of eletrostti intertions, tht is, eletrostti fore etween hrge NWs n olletors n the Coulom repulsion etween NWs eposite on seprte eletroes. As result, NWs woul eposit in prllel on the seprte eletroes. For exmple, Li et l. [12] use two piees of silion eletroes s the olletor to lign polymer NWs suh s polyvinyl pyrrolione (PVP), poly-(ethylene oxie) (PEO), polystyrene (PS), n polyrylonitrile (PAN), s well s inorgni NWA suh s SnO 2 n TiO 2. Interestingly, hollow NWA n e otine y using the eletrospinning methos s shown in Figs 6 n [57]. Aligne hollow TiO 2 NWs n e otine y linting the insie lyer of minerl oil. Besies, one n lso frite the PVP NWA y eletrospinning first, then eposit inorgni metl oxie mterils followe y heting proess to otin hollow NWs s shown in Fig. 6 [58]. Notly, externl mgneti fiel oul lso e use to hieve similr results [59,6]. For exmple, Yng et l. [6] use two prllel-positione permnent mgnets to reple the eletroes, so the mgneti fiel will rrnge the NWs ontining mgneti nnoprtiles uner mgneti fiel (Fig. 6). Rotting olletor ssiste metho This metho is to reple the stti olletor in onventionl eletrospinning metho with rotting olletor [61]. Mrh 216 Vol.59 No.3 23

5 SCIENCE CHINA Mterils Figure 5 Shemti igrm for lignment vi eletrospinning, inluing fiel ssiste metho, rotting olletor ssiste metho, n ner-fiel metho. Plsti syringe PVP/Ti(OiPr) 4 Hevy minerl oil Power Supply Metlli neele Sili pillry 5 nm S N S N V High voltge power supply Coxil jet Figure 6 Asse mling NWs y eletrospinning with fiel ssiste. () Shemti igrm for ssemling hollow NWs vi pir of prllel seprte eletroes. () Snning eletron mirosopy (SEM) imge of ligne hollow TiO 2 NWs. Reprinte with permission from Ref. [57] (Copyright 24, Amerin Chemil Soiety). () SEM imge of ligne hollow ZnO NWs. Reprinte with permission from Ref. [58] (Copyright 29, Amerin Chemil Soiety). () Assemling NWs vi mgneti-fiel-ssiste metho. Reprinte with permission from Ref. [6] (Copyright 21, WILEY-VCH Verlg GmH & Co. KGA). Generlly the rottion spee of the olletor hs signifint influene on the lignment of the NWs [62]. Too high or too low spee will le isorere morphology. Reently, ifferent shpes of olletors inluing wire rum [54], is or one hve een use to improve the lignment of the NWs [63,64]. Ktt et l. [54] use opper wire-frme rum supporte with two non-onuting isks s olletors to lign NWs. Chrge NWs will e strethe n spn ross the gp etween the opper wires uner eletrostti intertions. This strtegy n lign NWs in lrge sle n the lignment qulity is minly ffete y the rottion rte s shown in Fig. 7. Another moe is to lign NWs y using the shrp ege of is olletor whih offers the jet pulling fore long the tngent line of is. Highly orere n ense NWA of poly(l-ltie-o-ε-proltone) [P(LLA-CL)] n e otine on ny sustrtes uner n pproprite rotting spee (Figs 7 n ) [63,65]. 24 Mrh 216 Vol.59 No.3

6 SCIENCE CHINA Mterils REVIEWS Syringer Polymer jet Rotting isk olletor 2 μm Figure 7 Assemling NWs y eletrospinning with rotting olletor. () Nylon NWs re ligne on opper wires. Reprinte with permission from Ref. [54] (Copyright 24, Amerin Chemil Soiety). () Assemling NWs with isk olletor. () Optil imge of ligne P(LLA-CL) NWs. Reprinte with permission from Ref. [63] (Copyright 24, Elsevier). Ner-fiel ele trospinning metho n other moifitions Besies the two strtegies mentione ove, more improvements suh s onutive temp lte metho [66,67], entri fugl eletrospinning [68 7], n n er-fiel eletrospinning methos [71 74] hve lso een evelope. Conutive templte metho n e use to prepre NWs with omplex orere rhitetures n ptterns [67]. Usully, the onutive templtes re me of woven wires s shown in Fig. 8. Coulom intertions etween positive n negtive hrges will le the NWs to lign long the wires. Moreover, oth imeter of the metl wire n istne etween two protrusions hve influene on the prllelism n ensity of the rry, respetively. Smll imeters of NWs re inline to form prllel rry n ensity inreses with eresing istne etween the protrusions. These speifilly esigne onutive templte olletors hve gret potentil for the frition of ptterne firous mts whih my e wiely pplie in iomeiine n its inustry (Fig. 8). A entrifugl or rotting jet metho n lso lign NWs onveniently. The jet is ylinril olletor euse of the opposite hrges etween the neele n the olletor s shown in Fig. 8. High ensity rrys even lign 3D struture or ny ritrry shpe y hnging the geometry uner not very high voltge n esily operte proess vi this tehnique (Fig. 8). Interestingly, Brossmy et l. [68] omine entrifuge-spinning with tritionl eletrospinning whih n frite superfine NWAs t low voltge (2.8 3 kv) n slow rotting spee (39 rpm). Most of the ove strtegies n otin lrge re NWAs, ut it is hr to just iniviul NWs. Ner fiel eletrospinning is high-spee, iniviully ontrolle NWAs frition metho (Figs 8e n f). The istne etween eletroes n olletors is very short (5 μm 1 mm) n the work voltge is low ( kv). It is so lle iret write tehnique euse it n urtely eposit NWs on the sustrte just like writing [73]. Suh highly ontrollle writing metho enefits mny pplitions like miroeletronis n sensors [74]. APPLICATIONS BASED ON NWA NWs frite y eletrospinning methos n e iretly eposite on the trgeting sustrte n therefore voi the impurities or efets inue y trnsfer. Moreover, well ligne rrys n e utilize in eletronis n optoeletronis se on 1D nnomterils. In this prt, we onentrte on the pplitions of NWA frite y eletrospinning in eletronis n optoeletronis. Eletroni evies Compre with tritionl isorere NW film evies, NWA hs iret n fst rrier trnsport hnnel whih improves the eletroni properties of evies, furthermore, this regulr n uniform struture is enefiil to integrtion of eletroni iruits. Eletroes n FET NWA n e utilize s oth eletroes n onuting hnnel in evies. Lin et l. [75] synthesize ZnO NWs omposite with Ag nnoprtiles to stuy the eletril ehvior with ifferent Ag ontent. The shemti of evie is shown in Fig. 9. Ag nnoprtiles were ope y in situ photohemil reution of silver nitrte mixe with zin nitrte. I-V urves emonstrte tht urrent is Mrh 216 Vol.59 No.3 25

7 SCIENCE CHINA Mterils Flexile ir foil Fiers Rotting Polymer pthwy reservoir Colletor e Dispensing eletroe nozzle Polymer roplet High voltge power supply HV Tylor one 1 mm Sustrte f 5 nm 1 μm Figure 8 Assemling NWs y eletrospinning with other pprohes. () SEM imge of ptterne olletor. () Optil imge of eletrospun mt ollete using the olletor in (). Reprinte with permission from Ref. [67] (Copyright 27, WILEY-VCH Verlg GmH & Co. KGA). () Shemti igrm of ssemling NWs vi rotry jet-spinning. () SEM imge of the ligne polyethylene oxie (PEO) NWs. Reprinte with permission from Ref. [68] (Copyright 21, Amerin Chemil Soiety). (e) Shemti igrm of the printing proess. (f) SEM imges of printe PEO NWs. Reprinte with permission from Ref. [74] (Copyright 211, Amerin Chemil Soiety). remrkly enhne when Ag is e. The urrent is higher thn tht of pure ZnO NW evie y seven orers of mgnitues when the Ag ontent ws 5%, s shown in Fig. 9. Detile eletronil intrinsi oeffiient t s swith voltge (V ) n eletril nonliner oeffiient α re shown in Fig. 9. V ereses euse Ag ereses the numer of ZnO grin ounries n metl Ag prtiles my le to n inrese of lekge urrent [76,77]. Orgni NWs hve the following vntges suh s esy to esign moleules to tune eletroni properties n relize lrgesle synthesis t low ost, well flexiility n light weights [78,79]. They re lso promising lokings for flexile eletroni n optoeletroni evies [8,81]. Min et l. [82] use n orgni NW printer to frite well-ligne P3HT- PEO NWs with high-spee, to form n FET on 1 nm Au with ottom gte esign. Trnsfer hrteristis of P3HT- NW FET with 3% PEO t ifferent numers of wires re shown in Fig. 9, whih emonstrtes p-type hrteristi. The mximl on-urrent inreses s the numer of NWs inreses. Furthermore, this tehnique n e use to frite nno-hnnel trnsistors y printing nother poly(9-vinyl rzole) (PVK) NWAs followe soniting or hesive tpes ething proess. Fig. 9e shows p-type FET properties n short hnnel effet [83]. Certinly, this tehnique is very onvenient to frite lrge-re NW trnsistor rry on rigi or flexile sustrte suh s wfer or flexile plsti s shown in inset of Fig. 9f. The verge moility of FET is 3.8±1.6 m 2 V 1 s 1 (~1 evies), suggesting the promising future for mss proution. Gs sensor Compre with isorere NW films, NWAs hve muh lrge speifi surfe re s to the stright n prllel morphology. Nno-ligne fier rrys will emonstrte higher sensitivity [84]. Hollow ZnO NWAs were otine vi removing polyvinyl-ette (PVA) insie the omposites [58]. SEM imges of the s-spun PVA fiers re shown in Fig. 1. The left is the rnomly istriute PVA NWs, the right is the ligne rrys, inset in the right shows tht the NWs re hollow struture, n imeter is out 5 6 nm. As shown in Fig. 1, the qusi-ligne NWAs hve 2-fol higher sensitivity for NO 2 ompre with rnom fiers. An this enhnement is lso emonstrte t ifferent onentrtions (2, 4, 6, 8, 1 ppm, respetively). This work ws followe y Liu et l. [85]. They opte 26 Mrh 216 Vol.59 No.3

8 SCIENCE CHINA Mterils REVIEWS V μ V C (V) e 3 f 3 I D ( V D = 5 V 1 wire 3 wires 5 wires 9 wires V G (V) 2 I D ( V D (V) 5 V 15 V 3 No. of evies μ (m 2 V 1 s 1 ) Figure 9 Applition for eletronis. () Digrm for the Ag-ZnO NWA evie. () I-V hrteriztion of the NWA. () I-V properties t ifferent ontent of Ag. Reprinte with permission from Ref. [75] (Copyright 29, Amerin Institute of Physis). () Orgni FET of P3HT len NW FET with 3% PEO. (e) Output hrteristis (I -V ) of P3HT len NW FET with nnohnnel length. (f) Histogrm of the moility for lrge-re P3HT:PEOlen NW FET rry. Reprinte with permission from Ref. [82] (Copyright 213, Nture Pulishing Group). the sme frition pth n otine ZnO nnotues rry s shown in Fig. 1. Furthermore, they investigte the response for 1 ppm H 2 t ifferent tempertures (Fig. 1e.) The sensitivity of ZnO nnotues sensor for 1 ppm N 2 inreses from 2.3 to 3.6 when the temperture inreses from 2 to 4 C. Piezoeletri sensor Semionuting NWs with piezoeletri properties hve ttrte lrge reserh interest euse of the potentil pplition in onverting mehnil strins into eletriity [86]. Generlly, nnomterils use in mehnil energy svenging inlue: film se [87], n NW-se piezoeletri sensor [88,89]. Two typil piezoeletri NWs re frite from le zironte titnte (PZT) or polyvinyliene fluorie (PVDF) y eletrospinning [9,91]. PZT NWs prepre y n eletrospinning proess exhiit n extremely high piezoeletri voltge onstnt (g33,.79 V m N 1 ), high ening flexiility, n high mehnil strength [92]. Chen et l. frite ligne PZT NWs y epositing the NWs on the prepre eletroes using interigitte pltinum fine wire rrys, the ottom sustrte is silion. A lyer of polyimethylsiloxne (PDMS) is use to trnsport pplie pressure. Extrtion eletroes to n externl iruit re onnete to the Pt eletroes s shown in Fig. 11. The generte positive n negtive voltge is inue y the trnsient flow of eletrons when externl lo is on n remove [93]. Furthermore, the voltge is relte to the pressure whih is pplie on the piezoeletri sensor surfe s emonstrte in Fig. 11. However, in orer to otin goo piezoeletri property, high temperture nneling (6 C) proess for PZT NWs is generlly require [94]. PVDF NWs my e perfet nite in werle or implntle evies s to the omintion of mteril properties in lightweight n flexiility [95]. Persno et l. [91] utilize the high spee rotting isk to otin ligne PVDF NWAs in whih the length of NWs n reh severl entimeters. Interestingly, mesosopi joints with hunres of nnometers re forme etween overlpping fiers whih will enhne the mehnil roustness. The shemti illustrtion of n nlytil moel for the response of rrys of P(VDF-TrFe) fiers is shown in Fig. 11, inset is the photogrph for pplying pressure. Piezoeletri effet for ifferent effetive lengths is investigte s shown in Fig. 11. Th e voltge is inrese s the pressure inreses with liner reltionship. Moreover, the response slops, efine s sensitivity, lso inreses s the effetive length inres- Mrh 216 Vol.59 No.3 27

9 SCIENCE CHINA Mterils 2 μm NO 2 (ppm) Sensitivity (R/R o ) Resistne inreses y 1% Time (min) Qusiligne fiers Rnom fiers Thin film ZnO nnotues Ag Qurtz Al e Sensitivity (R ir /R gs ) μm Temperture ( C) Figure 1 Applition for gs sensors. () SEM imges for the hollow ZnO films n rrys. () Aetone sensitivity for thin film evies, rnom fier n qusi ligne fiers. Reprinte with permission from Ref. [58] (Copyright 29, Amerin Chemil Soiety). ( n ) Photogrph for hollow ZnO NWA n evie shemti igrm. (e) Sensitivity t ifferent tempertures. Reprinte with permission from Ref. [85] (Copyright 211, Elsevier). es from 3 to 6 mm. Theoretil pressure response onsists with the experimentl results t the effetive length of 6 mm. Photoetetor As mentione ove, eletrospinn ing is file wy to mss-proue ligne NWAs, n photoetetors se on NWA emonstrte high photoonutivity n fst response spee ompre with rnomly oriente NW films [96 1]. Photoetetor se on inorgni NWA 1D inorgni NWA hve een extensively stuie n use to frite high-performne optoeletroni evies ue to the lrge surfe to volume rtios n grnulr morphology [2,11]. Liu et l. [12] reporte full printing metho to otin ZnO NWA evies. Prllel rrys of NWs re forme on polyimie sustrte when ouple with progrmmle step motion s shown in inset of Fig. 12. The numer n the ensity of the ZnO NWs re tunle vi justing the hnnel length of the eletroes. Tking five NWAs evie s exmple, photourrent t wvelength rnging from 3 8 nm emonstrtes four orers of mgnitues seletivity higher for 365 nm thn for 6 nm wvelength whih is ttrtive for prtil UV sensing (Fig. 12) [13]. Muh more etils re shown in Fig. 12. It n e seen tht the responsivity is up to level of A W 1. This mens tht low optil input n le to high photourrent. In ition, the etetivity is s high s 1 17 Jones whih my ue to the high photourrent n low rk urrent t the sme time. Generlly eletrospun NWs hve lrger surfe re thn ommonly grown/synthesize NWs euse of the rough surfe n porous struture inue uring the sintering proess. Furthermore, grin ounries le to energy rriers tht my lok the rrier trnsport n introue the itionl n-ege moultion long xil iretion whih le to muh lower rk urrent [14]. Crriers n esily pss through this xil energy rriers t the grin ounries euse the rrier height is low t the illumintion of UV light. Further, this proess is expete to e muh fster thn the oxygen sorption/ 28 Mrh 216 Vol.59 No.3

10 SCIENCE CHINA Mterils REVIEWS PZT nnofiers PDMS polymer Pressing motion PZT nnogenertor Pltinum fine wires eletroes Voltge (V).1 Vo Extrtion eletroes ~.5 mm Silion sustrte.1.2 Relesing motion Time (s) X 1 Pressure 9 Experiment Theory X 3 L eff = 6 mm L eff Voltge (mv) 6 3 L eff = 4.5 mm L PVDF-TrFe L eff = 3 mm V Pressure (P) Figure 11 Applition for piezoeletri sensors. () Shemti view of the PZT NW genertor. () Voltge output mesure when using finger to pply ynmi lo on the top of the genertor. Reprinte with permission from Ref. [9] (Copyright 21, Amerin Chemil Soiety). () Shemti illustrtion of n nlytil moel for the response of rrys of P(VDF-TrFe) fiers, inset is the mnipultor for pplying pressure. () Voltge vs. pressure t ifferent effetive length. Reprinte with permission from Ref. [91] (Copyright 213, Nture Pulishing Group). esorption proess whih les to fst response. Bse on the results ove, our group fuse mium oxie into zin oxie NW to roen the spetrl response rnge of ZnO from UV to visile light [15]. The UV-vis sorption urve of ZnO-CO hyri NWs exhiits mixture of iniviul ZnO n CO NWs sorption urves s shown in Fig. 12. The pperne of pek t ~55 nm ientifies the existene of CO in hyri NW. Moreover, flexile photoetetor with high trnsprene of 95% ws frite on mi sustrte (Fig. 12e) to verify the goo flexiility of hyri NWs (Fig. 12f). Photoetetor se on heterostrutures NWA Heterostrutures whih oul le to sptil seprtion of the photo-generte rriers, re esigne to improve the photoeletri properties [16]. Hung et l. [17] omine the spin-oting with eletrospinning tehniques to otin p-type NiO films/n-type SnO 2 NW heterojuntion s shown in the shemti inset in Fig. 13. Here, t his heterojuntion photoioe emonstrtes photosensitivity of up to 1 5 t 1 V. This result is 1 times higher thn tht of the previous SnO 2 nnoelts photoetetor [18]. This enhne UV photoresponse is muh ovious in the reverse is region s shown in Fig. 13. At rev erse is of 5 V, the photoresponse urve reor presents more retngulr profile thn the one t forwr is of 5 V. Response time t 5 V is 1 2 s whih is shorter thn tht in the 5 V is. This improvement n lso emonstrte tht it is effetive t the interfe of inorgni-orgni struture [19]. Aligne TiO 2 NWAs s n interfil eletron olletion lyer were inserte into the thieno[3,4-]thiophene/enzoithiophene (PTB7) n [6,6]phenyl C71-utyri i y Nie et l. Devie rhiteture is shown in Fig. 13. The orgni-se photoetetors (OPDs) with one-wy ligne metl oxie NWs (AMONs) of TiO 2 emonstrte high etetivity of 1 13 Jones in Mrh 216 Vol.59 No.3 29

11 SCIENCE CHINA Mterils Asorne (.u.) CO ZnO-CO ZnO 1 3 Photourrent I ph (na) e 1 Trnsmittne (%) Polyrystlline ZnO GNWs Wvelength (nm) Responsivity (R i ) f Current (na) X O 2 O 2 O 2 N ph (sore photons s 1 ) O 2 O 2 O 2 O2 O2 O UV intensity (W m 2 ) Origin X X hv E C e h + E V X yles Speifi etetivity (Jones) Wvelength (nm) Wvelength (nm) Time (s) Figure 12 Applition for photoetetors. () Photogrph of evie, inset is the shemti igrm of printing set-up. () Photourrent with wvelength rnging from 3 to 8 nm. () The orresponing responsivity n speifi etetivity of the GNW photoetetor. Reprinte with permission from Ref. [12] (Copyright 214, Nture Pulishing Group). () Photoresponse t ifferent wvelengths. (e) Trnsmittne t ifferent wvelength, inset: HUST logo overe y the s-frite photoetetor. (f) Current-time urve etween the originl smple n the smple sujete to 2 ening yles. Reprinte with permission from Ref. [15] (Copyright 215, Wiley-VCH Pulishers, In). wie sorption rnge from 44 to 76 nm whih is 1 times higher thn tht of the OPDs. In ition, the evies with one-wy AMONs hve shorter response time n etter stility thn tht without AMONs (Fig. 13). No ovious hnge is oserve in response time for evies with one-wy AMONs of TiO 2 even fter 1 1 times of eletrilly re up, while for the OPDs, the stility ereses lot when re 1 8 times. The reson my e tht seprte rriers will form t the inorgni-orgni interfe whih oul filitte the hrge trnsport whih les to the fst response spee [11]. In summry, these heterostrutures provie innovtive evie rhitetures tht enle high performne n ro-n spetrl response. Humiity ssiste pho toetetor Oxygen plys n importnt role in UV photoresponse of NWs, n this priniple is lso suitle to NWAs [111]. However, the environmentl onition suh s reltive humiity (RH) n influene the sorption n esorption proess of oxygen on the NW surfe [112,113]. This influene ws reflete on the response time n response spee s Li et l. [113] investigte. Fig. 14 shows the response of ZnO nnowire t ifferent humiity in the rk n UV illumintion, respetively. In the rk, the response inreses slowly t RH lower thn 5%; however, this response inreses quikly when RH is over 5%. Upon UV illumintion, humiity influenes the response oviously. This response inreses from 1 to 2 when the RH inreses from 1% to 57%. However, the response ereses quikly when the humiity is over thn 57%. The rise n ey time of UV response is shown in Fig. 14. As the humiity inreses, the rise time ereses slowly from 26.7 s to 1.6 s, while the ey spee my e three times quiker t RH of 81% ompre with tht t 1% RH. Our group ttempte to onstrut ZnO-CO hyri NWAs se humiity sensors [15]. The photourrent ereses s the humiity inreses n photoresponse inreses first n then ereses when the humiity is rnging from 1% to 7% s shown in Fig. 14. The sorption/ esorption of surfe speies n rrier trnsport proess in the ry ir n high RH onition is shown in Fig. 14. At low RH, H 2 O moleules reple originl ionize oxygen n istriute inepenently. Therefore, the relese eletrons y the oxygen ions will ontriute to the onutivity in the rk when the RH is low. The wter my grully form monolyer on the NW surfe when the RH is high n les to wter issoition proess. The onutivity will hve shrp inrese euse the H + n OH n pro- 21 Mrh 216 Vol.59 No.3

12 SCIENCE CHINA Mterils REVIEWS Current (μa) F = 1 3 ~1 4 Drk UV Voltge (V) Tims (s) Current (μa) Off Off Off Off Off. Off Off Off Off Off 1. Forwr is Reverse is On On U Bis = ±5. V On On On On r r On On Without AMONs With one-wy AMONs Detetivity (Jones) 1 12 Al MoO 3 Ative lyer TiO 2 One-wy AMONs T r (us) Without AMONs With one-wy AMONs ITO glss Light Wvelength (nm) Re times Figure 13 Applition for photoetetors with heterojuntion. () I-V urve t UV light. () I-t urve mesure uner forwr n reverse is onitions, respetively. Reprinte with permission from Ref. [17] (Copyright 214, Royl Soiety of Chemistry). () Detetivity t ifferent wvelength with TiO 2 rry or without TiO 2 NWA. () Response time without AMONs of TiO 2 or with one-wy AMONs of TiO 2. Reprinte with permission from Ref. [19] (Copyright 213, Amerin Chemil Soiety). vie ioni onutivity. When the UV light is on uner the ry ir, photo-generte holes will omine with oxygen ion, inrese of onutivity is inue y the remining photo-generte eletrons. However, when the UV light is on uner high RH ir, the issoite H 2 O moleules will pture eletron n hole t the sme time, whih les to low ensity of rriers, quik reomintion n susequently fst photourrent ey will our when the UV light is swithe off [114]. CONCLUSIONS In this review, we me onise retrospetion on reporte ssemling methos for NWs, n primrily highlighte the importne of eletrospinning metho for NW frition n lignment s well s the sustntil improvement of this metho, suh s fiel ssiste metho, rotting olletor ssiste metho n ner-fiel ssiste metho. Highly orere NW strutures showe improvements in vrious res of eletronis n optoeletronis inluing flexile eletroes, FET, sensors, s well s photoetetors, whih lso pve the wy for future evelopment of high integrtion ensity iruits. However, there re lso some efiienies of eletrospinning metho neee to e improve. Fiel ssiste metho nnot preisely ontrol the numer of eletrospun NWs; rotting olletor ssiste metho hs prolem of low-qulity lignment; ner fiel ssiste metho is not suitle for mss proution. Moreover, the kins of Mrh 216 Vol.59 No.3 211

13 SCIENCE CHINA Mterils Respones rk Respones UV rise (s) ey (s) Reltive humiity (%) Reltive humiity (%) % 5% 7% Photourrent (na) Photourrent (na) Time (s) Figure 14 Applition for photoetetors t ssist of humiity. () The response of the ZnO nnowire evie in the rk or uner UV illumintion upon exposure to the ir with ifferent RH levels. Inset is SEM imges of the evie. () Rise n ey time t ifferent humiity. () Photoresponse t ifferent humiity. Reprinte with permission from Ref. [113] (Copyright 215, Wiley-VCH Pulishers, In). () Mehnism for low humiity n high humiity. Reprinte with permission from Ref. [15] (Copyright 213, Royl Soiety of Chemistry). onutive polymer whih suit for eletrospinning re still rre, while for insulting polymers generlly high temperture re require to remove them efore utiliztion whih woul result in eformtion of NWAs. Therefore, there is still gint room for improving the eletrospinning metho oth in tehnique n mterils hoie. As for tehnique, we onsier the lignment qulity n mss proution re the min issues in the future, whih finlly eies the potentil of prtil pplition. With regrs to mterils hoie, we hol the opinion tht hyri n omplementry mterils re the future reserhing hot spots, whih n e frite into speifi morphologies like ore-shell to exten the pplition fiel of evies. Reeive 25 Feurry 216; epte 22 Mrh 216; pulishe online 3 Mrh Zhi T, Yo J. One-Dimensionl Nnostrutures: Priniples n Applitions. New Jersy: John Wiley & Sons Hooken, Zhi TY, Li L, Wng X, et l. Reent evelopments in one-imensionl inorgni nnostrutures for photoetetors. Av Funt Mter, 21, 2: Xi YN, Yng PD, Sun YG, et l. One-imensionl nnostru ture: synthesis, hrteriztion, n pplitions. Av Mter, 23, 15: Liu JW, Ling HW, Yu SH. Mrosopi-sle ssemle nnowire thin films n their funtionlities. Chem Rev, 212, 112: Greiner A, Wenorff JH. Eletrospinning: fsinting metho for the preprtion of ultrthin fiers. Angew Chem Int E, 27, 46: Li D, Xi YN. Eletrospinning of nnofiers: reinventing the wheel? Av Mter, 24, 16: Zhou SS, Chen JN, Gn L, et l. Slle proution of self-supporte WS 2 /C nnofiers y eletrospinning s the noe for high performne lithium-ion tteries. Si Bull, 216, 61: Elnthn R, Kwit M, Ptolsky F, Voelker NH. Engineering vertilly ligne semionutor nnowire rrys for pplitions in the life sienes. Nno Toy, 214, 9: Li Y, Dun GT, Liu GQ, Ci WP. Physil proesses-ie perioi miro/nnostruture rrys y olloil templte tehnique: frition n pplitions. Chem So Rev, 213, 42: Hung ZP, Geyer N, Werner P, Boor JD, Gösele U. Metl-ssiste hemil ething of silion: review. Av Mter, 211, 23: Yu GH, Co A, Lieer CM. Lrge-re lown ule films of ligne 212 Mrh 216 Vol.59 No.3

14 SCIENCE CHINA Mterils REVIEWS NWs n ron nnotues. Nt Nnotehnol, 27, 2: Li D, Wng YL, Xi YN. Eletrospinning of polymeri n ermi nnofiers s unixilly ligne rrys. Nno Lett, 23, 3: Pn ZW, Di ZR, Wng ZL. Nnoelts of semionuting oxies. Siene, 291: Guiksen MS, Luhon LJ, Wng JF, Smith DC, Lieer CM. Growth of nnowire superlttie strutures for nnosle photonis n eletronis. Nture, 22, 415: Lee HW, Murlihrn P, Ruffo R, et l. Ultrthin spinel LiMn 2 O 4 NWs s high power thoe mterils for Li-ion tteries. Nno Lett, 21, 1: Limmer SJ, Co G. Sol-gel eletrophoreti eposition for the growth of oxie nnoros. Av Mter, 23, 15: Li ZY, Zhng HN, Zheng W. Highly sensitive n stle humiity nnosensors se on LiCl ope TiO 2 eletrospun nnofiers. J Am Chem So, 28, 13: Long YZ, Yu M, Sun B, Gu CZ, Fn ZY. Reent vnes in lrgesle ssemly of semionuting inorgni NWs n nnofiers for eletronis, sensors n photovoltis. Chem So Rev, 212, 41: Yng PD. Wires on wter. Nture, 23, 425: Whng D, Jin S, Wu Y, Lieer CM. Lrge-sle hierrhil orgniztion of nnowire rrys for integrte nnosystems. Nno Lett, 23, 3: Liu JW, Wng JL, Hung WR, et l. Orering Ag nnowire rrys y glss pillry: portle, reusle n urle SERS sustrte. Si Rep, 212, 2: Wng DW, Chng YL, Liu Z, Di HJ. Oxition resistnt germnium NWs: ulk synthesis, long hin lknethiol funtionliztion, n Lngmuir-Blogett ssemly. J Am Chem So, 25, 127: Kim YK, Kim DI, Prk J. File trnsfer of thikness ontrollle poly(methyl methrylte) ptterns on nnometer sle onto SiO 2 sustrtes vi miroontt printing omine with simplifie lngmuir-shefer tehnique. Lngmuir, 28, 24: Ahry S, Pn AB, Belmn N, Efrim S, Goln Y. A semionutor-nnowire ssemly of ultrhigh juntion ensity y the Lngmuir-Blogett tehnique. Av Mter, 26, 18: Ptl I, Ahry S, Zeiri L, et l. Synthesis, two-imensionl ssemly, n surfe pressure-inue olesene of ultrnrrow PS NWs. Nno Lett, 27, 7: Kim F, Kwn S, Akn J, Yng PD. Lngmuir-Blogett nnoro ssemly. J Am Chem So, 21, 123: Yu GH, Li XL, Lieer CM, Co AY. 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15 SCIENCE CHINA Mterils 55 Mtthews JA, Wnek GE, Simpson DG, Bowlin GL. Eletrospinning of ollgen nnofiers. Biomromoleules, 22, 3: Pn H, Li L, Hu L, Cui XJ. Continuous ligne polymer fiers proue y moifie eletrospinning metho. Polymer, 26, 47: Li D, Xi YN. Diret frition of omposite n ermi hollow nnofiers y eletrospinning. Nno Lett, 24, 4: Choi SH, Ankonin G, Youn DY, et l. Hollow ZnO nnofiers frite using eletrospun polymer templtes n their eletroni trnsport properties. ACS Nno, 29, 3: Yng DY, Lu B, Zho Y, Jing X. Frition of ligne firous rrys y mgneti eletrospinning. Av Mter, 27, 19: Liu YQ, Zhng XP, Xi YN, Yng H. Mgneti-fiel-ssiste eletrospinning of ligne stright n wvy polymeri nnofiers. Av Mter, 21, 22: Teo WE, Rmkrishn S. A review on eletrospinning esign n nnofier ssemlies. Nnotehnology, 26, 17: R89 R16 62 Shim HS, N SI, Nm SH, et l. Effiient photovolti evie fshione of highly ligne multilyers of eletrospun TiO 2 nnowire rry with onjugte polymer. 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16 SCIENCE CHINA Mterils REVIEWS e ZnO nnowire photoetetors with ultr-high etetivity. Nt Commun, 214, 5: Lin CH, Chng SJ, Chen WS, Hsueh TJ. Trnsprent ZnO-nnowire-se evie for UV light etetion n ethnol gs sensing on -Si solr ell. RSC Av, 216, 6: Hossin FM, Nishii J, Tkgi S, et l. Moeling n simultion of polyrystlline ZnO thin-film trnsistors. J Appl Phys, 23, 94: Zheng Z, Gn L, Li HQ, et l. A fully trnsprent n flexile ultrviolet-visile photoetetor se on ontrolle eletrospun ZnO- CO heterojuntion nnofier rrys. Av Funt Mter, 215, 25: Tin W, Zhi TY, Zhng C, et l. Low-ost fully trnsprent ultrviolet photoetetors se on eletrospun ZnO-SnO 2 heterojuntion nnofiers. Av Mter, 213, 25: Hung SY, Wu H, Mtsur K, Cheng J, Pn W. File ssemly of n-sno 2 nnoelts-p-nio heterojuntions with enhne ultrviolet photoresponse. Chem Commun, 214, 5: Hung SY, Wu H, Zhou M, et l. A flexile n trnsprent ermi nnoelt network for soft eletronis. NPG Asi Mter, 214, 6: e86 19 Nie R, Wng YY, Deng XY. Aligne nnofiers s n interfil lyer for hieving high etetivity n fst-response orgni photoetetors. ACS Appl Mter Interfes, 214, 6: Deng MJ, Shen SL, Wng XW, et l. Controlle synthesis of AgInS 2 nnorystls n their pplition in orgni-inorgni hyri photoetetors. CrystEngComm, 213, 15: Kin H, Yn HQ, Messer B, Lw M, Yng PD. Nnowire ultrviolet photoetetors n optil swithes. Av Mter, 22, 14: Hsu CL, Li HH, Hsueh TJ. Wter-n humiity-enhne UV etetor y using p-type L-ope ZnO NWs on flexile polyimie sustrte. ACS Appl Mter Interfes, 213, 5: Li CL, Wng XX, Zho Y, Fong H, Zhu ZT. Effets of humiity on the ultrviolet nnosensors of ligne eletrospun ZnO nnofiers. RSC Av, 213, 3: Li YB, Vlle FD, Simonnet M, Ym I, Deluny JJ. Competitive surfe effets of oxygen n wter on UV photoresponse of ZnO NWs. Appl Phys Lett, 29, 94: 2311 Aknowlegements This work ws supporte y the Ntionl Nturl Siene Fountion of Chin ( , n ), Ntionl Bsi Reserh Progrm of Chin (215CB9326), Progrm for HUST Interisiplinry Innovtion Tem (215ZDTD38) n the Funmentl Reserh Funs for the Centrl University. The uthors re inete for the kin permission from the orresponing pulishers/uthors to reproue their mterils, espeilly figures use in this rtile. Author ontriutions Zheng Z, Gn L n Zhi TY oneive the stuy. Zheng Z n Gn L wrote the mnusript. Gn L n Zhi TY moifie the mnusript. All uthors isusse on the mnusripts struture, rguments n onlusions. Conflit of interest The uthors elre tht they hve no onflit of interest. Mrh 216 Vol.59 No.3 215

17 SCIENCE CHINA Mterils Zhi Zheng reeive his BS egree in inorgni non-metlli mterils from Shnxi University of Siene n Tehnology in 212. Currently, he is PhD nite in Prof. Tinyou Zhi s group t the Shool of Mterils Siene n Engineering, HUST. His sientifi reserh onentrtes on the preprtion of NWs vi eletrospinning for eletroni n optoeletroni evies. Lin Gn reeive his BS egree in hemistry from Wuhn University in 25, n PhD egree in physil hemistry from Peking University uner the supervision of Prof. Xuefeng Guo in 212. Currently, he is working t the Shool of Mterils Siene n Engineering, HUST. His reserh interest fouses minly on the hemil vpor eposition (CVD) synthesis of two-imensionl (2D) nnomterils, suh s grphene, TMDs, et., n the eletroni/optoeletroni properties n pplitions of these 2D mterils. Tinyou Zhi reeive his BS egree in hemistry from Zhengzhou University in 23, n then reeive his PhD egree in physil hemistry from the Institute of Chemistry, Chinese Aemy of Sienes (ICCAS) uner the supervision of Prof. Jinnin Yo in 28. Afterwrs he joine the Ntionl Institute for Mterils Siene (NIMS) s JSPS postotorl fellow of Prof. Yoshio Bno s group n then s n ICYS-MANA reserher within NIMS. Currently, he is Chief Professor of the Shool of Mterils Siene n Engineering, HUST. His reserh interests inlue the ontrolle synthesis n explortion of funmentl physil properties of inorgni funtionl nnomterils, s well s their promising pplitions in energy siene, eletronis n optoeletronis. 静电纺丝法制备纳米线阵列及其在电子与光电子领域中的应用郑志, 甘霖, 翟天佑 摘要一维纳米线的有序化排列问题, 是决定其未来在高集成微纳电路中应用前景的关键因素. 本综述对目前能够实现纳米线有序化排列的技术方法做了一个简要的归纳, 重点阐述静电纺丝技术在纳米线制备和有序化排列方面的优势及相关技术和应用进展. 本文首先按技术特点将目前纳米线有序化排列技术大致分为 先生长后排列, 先排列后生长 以及 边生长边排列 ( 即静电纺丝技术 ) 三大类, 并对各类方法的优缺点进行了简要评述. 然后着重介绍静电纺丝技术及其相关技术进展, 并进一步展示了当前基于静电纺丝技术制备的纳米线阵列在微纳电极 场效应晶体管 传感器以及光探测器等方向的应用. 最后就静电纺丝技术的未来发展做了简要展望. 综上, 由于静电纺丝技术在一维材料制备及其有序化排列方面的简便性和低成本优势, 其必将在基于一维材料的电子学 / 光电子学领域具有广阔的应用前景. 216 Mrh 216 Vol.59 No.3