RSC Avnes This is n Aepte Mnusript, whih hs een through the Royl Soiety of Chemistry peer review proess n hs een epte for pulition. Aepte Mnusripts re pulishe online shortly fter eptne, efore tehnil eiting, formtting n proof reing. Using this free servie, uthors n mke their results ville to the ommunity, in itle form, efore we pulish the eite rtile. This Aepte Mnusript will e reple y the eite, formtte n pginte rtile s soon s this is ville. You n fin more informtion out Aepte Mnusripts in the Informtion for Authors. Plese note tht tehnil eiting my introue minor hnges to the text n/or grphis, whih my lter ontent. The journl s stnr Terms & Conitions n the Ethil guielines still pply. In no event shll the Royl Soiety of Chemistry e hel responsile for ny errors or omissions in this Aepte Mnusript or ny onsequenes rising from the use of ny informtion it ontins. www.rs.org/vnes
Pge 1 of Journl Nme RSC Avnes Dynmi Artile Links Cite this: DOI:.39/0xx00000x www.rs.org/xxxxxx ARTICLE TYPE Enhne visile light phototlyti tivity of polyniline-rystlline TiO 2 -hlloysite omposite nnotues y tuning the i opnt in the preprtion 2 Cuiping Li, * Tinzhu Zhou, Tinwen Zhu n Xueyun Li Reeive (in XXX, XXX) Xth XXXXXXXXX XX, Aepte Xth XXXXXXXXX XX DOI:.39/000000x Tuulr hlloysite minerls re use s support for the frition of one-imensionl polynilinerystlline TiO 2 -hlloysite omposite nnotues in the presene of ifferent i opnt t low temperture. By simply justing the iity of retion system, PANI-rystlline TiO 2 -HA omposite nnotues ompose of ntse, mixe phse TiO 2 n ifferent PANI reox stte re otine. The iity of retion system is tune y HNO 3, HCl, H 2 SO 4 n H 3 PO 4, respetively. The tritionl therml tretment for rystlline trnsformtion is not require, thus intt hlloysite struture n e gurntee. The XRD n UV-vis results show tht the surfe polyniline sensitiztion hs no effet on the rystlline struture of hlloysite n the light response of TiO 2 is extene to visile-light regions, respetively. The visile light phototlyti tivity of polyniline-rystlline TiO 2 -hlloysite with HCl tuning the iity (ph 0.) n 1% volume rtio of niline to titnium isopropoxie in the preprtion (P-TH/0./1%-HCl) is superior to those of smples with H 2 SO 4, HNO 3 n H 3 PO 4 tuning the iity in the preprtion t the sme iity n volume rtio of niline to titnium isopropoxie. Suh superior phototlyti tivity of P-TH/0./1%-HCl is minly ue to the enhne visile light sorption n eletril onutivity. Furthermore, reoping P-TH/0./1%-HCl with H 2 SO 4 n H 3 PO 4 emonstrtes its phototlyti tivity is erese, initing the i opnt in the preprtion n reoping proess ply importnt role to the phototlyti tivity of the polyniline-rystlline TiO 2 -hlloysite omposite nnotues. Moreover, the supporte tlyst llows them to e esily seprte from the solution. 1. Introution During the pst ees, ly minerl supporte tlysts with high effiieny hve een wiely stuie for potentil pplition in ir purifition n phototlyti egrtion of orgni pollutnts, owing to their lrge surfe re, high tion exhnge pity n the exellent enrihment ility for orgni retnts either on their externl surfes or within their interplnr spes y interltion or sustitution. 1-6 Among the ly minerl fmilies, tuulr hlloysite ( hemil formul of Al 2 Si 2 O (OH) 4.2H 2 O) whih is similr to kolinite exept for the 3 presene of n itionl wter monolyer etween the jent ly lyers, hs grnere prtiulr interests ue to its verstile fetures of lrge surfe re, high porosity, n tunle surfe hemistry, whih enle this nnomteril to e utilize s n ttrtive support for the ssemly of smll-size metls n metl-oxie n hyroxie ggregtes (lusters n nnoprtiles). 7-11 Furthermore, the ly nnotues possess the vntges of high stility, resistiility ginst orgni solvents, n ese of isposl or reusility s well. 12 Compre to ron nnotues, they re eonomilly ville nturl mterils n 4 hve mny unique hrteristis inluing ifferent outsie/insie hemil properties n equte hyroxyl groups on the surfe.,12 These groups n ret with orgnohlorosilnes n lkoxies giving ovlently one orgni-inorgni erivtives, 13-17 whih is useful for nhoring tlyst prtiles on the hlloysite surfe. Reently, vrious tlyst ompouns (ATRP tlyst, silver n ruthenium) loe on the tuulr hlloysite minerl hve een reporte with exellent tlyti performne. 8- On the other hn, phototlyti proesses involving TiO 2 semionutor prtiles uner UV light illumintions hve een shown to e potentilly vntgeous n useful in the tretment of orgni pollutnts. 18,19 However, they re limite to onsierle egree euse of the high ost of their lrge-sle proution, ouple with the low solr energy onversion effiieny n the high hrge reomintion rte of photogenerte eletrons n holes. 19, In reent yers, lrge numer of methos hve een reporte to improve the phototlyti tivity of TiO 2, inluing the oping of trnsition metl or non-metl ions, 21 the eposition of nole metls, 22 the 6 surfe sensitiztion of yes 23 n the preprtion of omposite semionutors. 24 Though the ove moifitions n prtly improve the phototlyti tivity of TiO 2, there still exist some key prolems unresolve, for exmple, omplite syntheti or moifition proeures, ope mterils suffer from instility prolem n iffiulty in tlyst reyling. So from the point of view to remey the environment, it is very urgent to evelop TiO 2 se phototlyst with simple syntheti proeures, high This journl is The Royl Soiety of Chemistry [yer] [journl], [yer], [vol], 00 00 1
, RSC Avnes Pge 2 of tivity, visile-response, high stility n esy reyling. Reently, it hs een shown tht TiO 2 hyriizing with onuting polymer n inrese the phototlyti tivity towrs the eomposition of orgni moleules when irrite with visile light. 2 Polyniline (PANI) is one of the most frequently investigte onuting polymers for mny resons: it is environmentlly stle, inexpensive, n its eletril onutivity n e esily tune vi speil proton oping mehnism. 26 It is onjugte polymer tht n serve s n insultor, semionutor, or onutor, epening on the egree of protontion n the preprtion onition. Therefore, onjugte polymers with wie n gp inorgni semionutors re reeiving ttention for optil, eletroni, phototlyti n photoeletri onversion pplitions. 27-29 Sine onuting PANI ehves s p-type semionutor with n gp sorption ege tht n exten into the rnge of visile light n exhiits goo environmentl stility, the omintion of TiO 2 n PANI shoul overome the rwks of the former. Reently, the omintion of PANI n TiO 2 to improve their performne of UV light, 29 sunlight n visile light tivity 2 hs een reporte. It shows PANI plys the role of photosensitizer n TiO 2 sensitize y PANI hs enhne phototlyti tivity. Furthermore, the oping type 31 n oping onentrtion 32 n ply signifint role in 2 etermining the struturl properties of PANI/TiO 2. Reently, Slem et. hve emonstrte the UV phototlyti tivity of PANI/TiO 2 forme in the presene of ifferent is follows the orer: H 2 SO 4 >H 3 PO 4 >HCl>HNO 3 n ereses with the inrese of HCl onentrtion, 29 whih is ifferent from our 3 4 previous results tht phototlyti tivity of PANI-TiO 2 -HA prepre t ph 0. shows higher phototlyti tivity thn tht prepre t ph 1.. 33 So even the effet of i opnt in the preprtion on the phototlyti tivity of PANI/TiO 2 uner UV light irrition hs een investigte pproximtely, it my emonstrte ifferent tren on the PANI-TiO 2 -HA prepre in the presene of ifferent i t low temperture. An the reporte work minly fous on hyriizing PANI on the prepre or ommeril TiO 2. The prepre or ommeril TiO 2 usully involve in high-temperture therml tretment to trnsform the morphous TiO 2 into rystlline phse, whih will le to the TiO 2 nnoprtiles ggregtion, s well s the teneny of rystllites growth. Reently, some reports hve emonstrte the frition of rystlline TiO 2 on hlloysite minerls uner mil onitons. 34,3 For exmple, one-step solvotherml tretment t 1 C is pplie to prepre ntse/hlloysite minerl omposites, whih emonstrte higher UV n visile light phototlyti tivity in eomposing NO x gs. In our previous stuies, 33,36 we hve synthesize rystlline TiO 2 -hlloysite n PANI-rystlline TiO 2 -hlloysite omposite nnotues with HNO 3 s i opnt n FeCl 3 s oxint for PANI t low temperture n phototlysis test results revel the phototlyti tivity will e ffete y the ph vlue n the volume rtio of ANI to TTIP. The highest phototlyti tivity is hieve with the omposite phototlysts prepre t ph 0. n 1% volume rtio of ANI n TTIP owing to the sensitizing effet of polyniline n the effetive hrge trnsfer from the photoexite PANI sensitizer to TiO 2. In the present work, heterogeneous PANI-rystlline TiO 2 -HA nnotues re one-pot synthesize in the presene of vrious is t low temperture y the similr proeure s tht reporte in referene 33. By simply justing the iity of retion system, PANI-rystlline TiO 2 -HA omposite nnotues with ifferent TiO 2 rystl phse n PAN reox stte re otine, where high temperture lintion is not require. Thus intt 6 hlloysite struture n e gurntee n the growth of TiO 2 rystllites n e voie. The effet of i opnt in the preprtion on the phototlyti tivities of PANI-TiO 2 -HA heterorhitetures uner visile light irrition re investigte systemtilly. Furthermore, the phototlyti tivity n e simply tune y the type n onentrtion of i opnt in the reoping proess. 2. Experimentl 2.1. Mterils The hlloysite (HA) minerls were purhse from Imerys 7 Tlewre Asi Limite. Titnium isopropoxie (TTIP) ws purhse from Nnjing Doning Chemil Co., Lt. Isopropyl lohol, niline (ANI) n mmonium persulfte ((NH 4 ) 2 S 2 O 8 ) were purhse from Sinophrm Chemil Regent Co., Lt. All regents were nlytil gre n use without further purifition. 8 9 0 1 1 1 2.2. One-pot synthesis of heterogeneous PANI-TiO 2 -HA nnotues in the presene of ifferent i. Titnium isopropoxie (TTIP) ws use s preursor. To otin the heterogeneous PANI-TiO 2 -HA nnotues without forming TiO 2 in the ontinuous mei, the TTIP onentrtion ws ontrolle t 0.01-0.0 M. In the preprtion of heterogeneous PANI-TiO 2 -HA nnotues, TTIP, isopropyl lohol n hlloysite minerl s onentrtions of ifferent iity system were fixe n the iity of the system ws juste y ltering the fee mount of 2 M i. The molr rtio of (NH 4 ) 2 S 2 O 8 to ANI ws mintine t 1:1. The retion temperture ws ontrolle t 6 C. 33,36 A typil proeure with HCl s ph tuning gent n i opnt ws s follows: TTIP (2 ml), isopropyl lohol ( ml), n hyrohlori i (2 M, 79 ml) were mixe uner stirring t room temperture for 1 h to form onentrte trnsprent sol. By ing istille wter to the sol until finl volume of 0 ml, the finl sol of ph 0. ws otine. Hlloysite (HA, 1 g), niline (ANI, 0.02 ml) n (NH 4 ) 2 S 2 O 8 (0.0499 g) were e to the ove sol (0 ml) uner stirring for 2 h. The ispersion ws then hete t 6 C for 24 h uner stirring to form PANI-ntse/rutile-HA heterorhiteture, whih ws enote s P-TH/0./1%-HCl. The iity of the sol n PANI ontent were juste y ltering the fee mount of 2M i n ANI, respetively. In this wy, PANI-TiO 2 -HA omposite nnotues with 1% volume rtio of ANI to TTIP in the presene of HNO 3, H 2 SO 4 n H 3 PO 4 were prepre; these were lele s P-TH/0./1%-HNO 3, P- TH/0./1%-H 2 SO 4 n P-TH/0./1%-H 3 PO 4, respetively. Similrly, PANI-TiO 2 -HA omposite nnotues prepre t the initil ph of the TiO 2 sol of 1. with 1% volume rtio of ANI to TTIP in the presene of HNO 3, HCl, H 2 SO 4 n H 3 PO 4.were enote s P-TH/1./1%-HNO 3, P-TH/1./1%-HCl, P- TH/1./1%-H 2 SO 4 n P-TH/1./1%-H 3 PO 4, respetively. To onfirm the sensitiztion effet of PANI on the phototlyti tivities of the omposite nnotues, the TiO 2 -HA omposite nnotues (TH/1.-HCl, TH/0.-HCl) in the presene of HCl were prepre with the sme proeure s tht of the heterogeneous PANI-rystlline TiO 2 -HA nnotues exept tht ANI n (NH 4 ) 2 S 2 O 8 were not e. The PANI-TiO 2 -HA heterorhitetures (P-TH/X/Y-Z) were seprte y entrifugtion, wshe with wter severl yles to neutrl n 2 Journl Nme, [yer], [vol], 00 00 This journl is The Royl Soiety of Chemistry [yer]
Pge 3 of RSC Avnes 2 3 4 trnsferre to oven to ry t 6 C. 2.3. Chrteriztion Heterogeneous PANI-TiO 2 -HA nnotues (P-TH/X/Y-Z) were isperse in ethnol n spre onto ron-ote opper gris for TEM (JSM-) equippe with n energy ispersive X-ry spetrum (EDX, In Energy-0) t n elerting voltge of 0 kv. Wie-ngle X-ry power sttering (XRD, Rigku D/mx-3B) with Cu Kα rition ws use to hrterize the rystlline phses in the 2θ rnge - t sn rte of /min. FT-IR mesurements were performe on Thermo Niolet instrument. Potssium romie pellets ontining 0.% of the smples were use in FT-IR experiments n 64 sns were umulte for eh spetrum in sorne t spetrl resolution of 2 m -1. The spetrum of ry KBr ws tken for kgroun sutrtion. UV-vis iffuse refletne spetr were mesure t room temperture in ir on Shimzu UV-21PC photometer over the rnge from 0 to 0 nm. X-ry photoeletron spetrosopy (XPS) mesurements were performe with n ESCAL2i-XL eletron spetrometer from VG Sientifi using 0W Al Kα rition. The se pressure ws out 3-9 mr. The ining energies were referene to the C1s line t 284.6 ev from ventitious ron. Eletril onutivity mesurements were performe with Agilent 4294 impene nlyzers t the room temperture. The testing frequeny ws Hz-1MHz. The smples were presse into 12.8 mm imeter isk for the mesurement. 2.4. Mesurement of phototlyti tivity The retions of the phototlyti egrtion of yes in solution were rrie out in qurtz th photoretor ontining ml mg/l rhomine B (RB) solution n 2 mg of the heterogeneous PANI-TiO 2 -HA nnotues (P-TH/X/Y-Z). The suspensions were mgnetilly stirre in the rk for 24 h to ttin sorption-esorption equilirium etween RB n P- TH/X/Y-Z. Susequently, the phototlyti egrtion experiments of RB over P-TH/X/Y-Z uner visile light irrition were performe using XPA-7 photohemil system (Xujing Eletromehnil Plnt, Nnjing, Chin). A 0 W Xe lmp (2< λ < 0 nm) with optil filter to eliminte the UV emission elow 0 nm ws use s visile light resoure 33,36 n the emission intensity on the suspensions surfe ws 24 mw/m 2. During the phototlyti experiments, the qurtz th photoretor without egsse ws sele in orer to voi the erese of the volume of the suspension n kept uner onstnt stirring without purge with inert gs n ir (O 2 ). Aequte liquots (6 ml) of the smple were withrwn in the ir fter perioi intervls of irrition, whih were entrifuge t 4 000 rpm for min, n then filtere through miroporous filter (pore size 0.4 µm) to remove the resiul tlyst prtiultes for nlysis. The onentrtion of filtrtes ws etermine y reoring the mximum sorne of RB t 3 nm with UV10 photometer over the rnge from 0 to 0 nm. 3. Results n isussion 3.1. Chrteriztion of the heterogeneous PANI-TiO 2 -HA nnotues A ommeril hlloysite minerl is selete s n exmple prent 6 7 8 support for prepring the heterogeneous PANI-rystlline TiO 2 - HA nnotue. The struture n morphology of the hlloysite minerl re hrterize with SEM n TEM. As shown in Fig. S1, the hlloysite preomintely onsists of ylinril tues - nm in imeter n 1-2 µm in length. TEM imge revels the empty lumen struture of hlloysite minerl n the inner imeter is - nm (Fig. S1 in ESI ). Perioiity in the iniviul lyer pking is etermine with XRD n is foun to e 0.73±0.02 nm, whih orrespons to ehyrte hlloysite (Fig. S2 in ESI ). XPS n EDX emonstrte tht elementl omposition of the hlloysite is s follows (tomi %): Al, 17.6; Si, 17.; O, 64.9 (Fig. S3, Fig. S4 in ESI ). Elements like C, Fe, Cu n N re not etete. The BET surfe re of the hlloysite minerls is 38.6 m 2 /g. 36 The ove t prove tht the support is hlloysite rih minerl. It is well known tht ph vlue ontrolle to reltively low vlue (ph<2) is ruil to filitte the formtion of rystlline TiO 2. 37 Uner suh onition, the growing rystlline TiO 2 speies suh s [Ti(OH) x (OH 2 ) 6-x ] (4-x)+ re positively hrge, 37 euse the ph vlue is lower thn the isoeletri point of TiO 2 (ph -7). In our previous pper, we hve prove tht when the ph is lower thn 2, the outer surfe of the tuulr hlloysite minerls is negtively hrge n n inue the inorgni TiO 2 nnorystls n PANI to grow onto the tuulr hlloysite minerls in situ in the presene of HNO 3 with FeCl 3 s oxint t low temperture. 33 In this stuy, we synthesize heterogeneous PANI-rystlline TiO 2 - HA nnotues t low temperture y the similr proeure s tht Fig. 1 TEM imges of the heterogeneous PANI-TiO 2-HA nnotues prepre t ph 1. of the strting sols y one-pot with 1% volume rtio of ANI to TTIP (P-TH/1./1%-Z): the ph of the strting sols is tune y ) HNO 3, ) HCl, ) H 2SO 4 n ) H 3PO 4; e) HRTEM imge of the smple s shown in (), reveling the ntse phse struture. of prepring the heterogeneous PANI-rystlline TiO 2 -HA This journl is The Royl Soiety of Chemistry [yer] Journl Nme, [yer], [vol], 00 00 3
, RSC Avnes Pge 4 of 2 nnotues in the presene of HNO 3, HCl, H 2 SO 4 n H 3 PO 4 with (NH 4 ) 2 S 2 O 8 s ANI s oxint. By simply justing the iity of retion system, TiO 2 rystlline phse n PANI reox stte n e tune. An y tuning the i opnt in the preprtion, the visile light phototlyti tivity of polyniline-rystlline TiO 2 -hlloysite omposite nnotues n e tune. In the previous stuy, 33 it shows the optimum volume rtio of ANI to TTIP is 1% for the enhne phototlyti tivity of PANI- TiO 2 -HA, so in the present work, the phototlyti tivity of PANI-TiO 2 -HA prepre in the presene of ifferent i n with 1% volume rtio of ANI to TTIP (P-TH/X/1%-Z) is investigte minly. A Reltive Intensity (.u.) B Reltive Intensity (.u.) e e 2Thet (Deg) 2Thet (Deg) Fig. 2 XRD spetr of heterogeneous PANI-TiO 2-HA nnotues prepre y one-pot with 1% volume rtio of ANI to TTIP t ph 1. (A) n 0. (B) of the strting sols: ) HA; the ph of the strting sols is tune y ) HNO 3, ) HCl, ) H 2SO 4 n e) H 3PO 4, respetively. : rutile (JCPDS No. 21-1276); : ntse (JCPDS No. 21-1272). At n initil ph vlue of 1., heterogeneous PANI-TiO 2 -HA nnotues with orse surfes re otine (Fig. 1) n note s P-TH/1./1%-Z. Compre with the prent hlloysite support, 3- nm grins re homogeneously eposite on the surfes of tuulr hlloysite minerls without visile ggregtion. The hollow lumen of the P-TH/1./1%-Z heterorhiteture is iserne lerly (Fig. 1). The ntse phse is verifie y high 3 4 resolution TEM (HRTEM) (Fig. 1e) n XRD (line -e in Fig. 2A). The TiO 2 in rutile phse grully ppers s inresing the iity of the strting sol. As n exmple, t ph vlue of the TiO 2 sol of 0., the representtive heterogeneous nnotues re otine with ntse/rutile phses oexisting (Fig. 2B, Fig. 3), whih re ite s P-TH/0./1%-Z. Fig. 3 shows tht some nnosize neeles or lrger nnoprtiles re grown n protrue from the orse ntse surfe t ph 0. for P- TH/0./1%-HNO 3 n P-TH/0./1%-HCl. An the heterogeneous P-TH/0./1%-HNO 3 n P-TH/0./1%-HCl omposite nnotues hve two istint regions in morphology, the nnoneeles (or lrger nnoprtiles) n the nnogrins, lele s A n B in Fig. 3, respetively. HRTEM (Fig. 3e,f) results revel tht the neeles of region A re in rutile phse with (1) lttie sping of 0.324 nm, where nnogrins in region B, whih orrespon to the orse surfe, re ientifie s ntse phse with (1) lttie sping of 0.3 nm (Fig. 3f). It hs to mention tht the morphology of PANI-TiO 2 -HA omposite nnotues prepre t ph 0. in the presene of ifferent i opnt is ifferent: nnoneeles n the nnogrins oexist on the surfe of HA for the PANI-TiO 2 -HA with HNO 3 (P-TH/0./1%-HNO 3 ) n HCl (P-TH/0./1%-HCl) tuning the ph n s i opnt, wheres -0 nm nnogrins n irregulr grins re oserve on the surfe of HA for the PANI-TiO 2 -HA with H 2 SO 4 (P-TH/0./1%- H 2 SO 4 ) n H 3 PO 4 (P-TH/0./1%-H 3 PO 4 ) tuning the ph n s i opnt, respetively. Furthermore, there re no PANI n TiO 2 in the ulk exept the P-TH/0./1%-H 3 PO 4 retion system, Fig. 3 TEM imges of the heterogeneous PANI-TiO 2-HA nnotues prepre t ph 0. of the strting sols y one-pot with 1% volume rtio of ANI to TTIP (P-TH/0./1%-Z): the ph of the strting sols is tune y ) HNO 3, ) HCl, ) H 2SO 4 n ) H 3PO 4; e, f) HRTEM imges of regions A n B, respetively, of the smple shown in ), reveling the ntse/rutile mixe phse struture. 4 Journl Nme, [yer], [vol], 00 00 This journl is The Royl Soiety of Chemistry [yer]
Pge of RSC Avnes initing hlloysite n inue TiO 2 nnorystlline n PANI to grow on the hlloysite minerl in situ simultneously. Although the morphology of P-TH/0./1%-H 2 SO 4 is ifferent from those of P-TH/0./1%-HCl n P-TH/0./1%-HNO 3, HRTEM n XRD (line in Fig. 2B) inite the TiO 2 is ntse/rutile mixe phse struture. The FT-IR spetr of heterogeneous PANI-TiO 2 -HA nnotues prepre t ph 1. (P-TH/1./1%-Z) n ph 0. (P-TH/0./1%- Z) with 1% volume rtio of ANI to TTIP re shown in Fig. SA n Fig. SB, respetively. For omprison, the spetr of prent hlloysite (line in Fig. S in ESI ) is lso given. Unfortuntely, the min hrteristi peks of PANI re not ler owing to the low volume rtio of ANI to TTIP (1%). In orer to well hrterize the PANI in PANI-TiO 2 -HA, the spetr of PANI- TiO 2 -HA with 0% volume rtio of ANI to TTIP prepre uner the similr onition re shown in Fig. 4A n Fig. 4B, respetively. The min hrteristi peks of PANI in P- TH/X/0%-HCl prepre t ph 1. n ph 0. re ssigne s follows: the n t 3412 (3414) m -1 is ttriute to N H A Asorne Intensity (.u.) B 3412 00 00 20 00 10 00 0 Asorne Intensity (.u.) 3414 Wvenumer (m -1 ) 13 11 12 1292 12341116 141299 4 00 00 20 00 10 00 0 Wvenumer (m -1 ) Fig. 4 FT-IR spetr of heterogeneous PANI-TiO 2-HA nnotues prepre y one-pot with 0% volume rtio of ANI to TTIP t ph 1. (A) n 0. (B) of the strting sols: the ph of the strting sols is tune y 2 ) HNO 3, ) HCl, ) H 2SO 4 n ) H 3PO 4, respetively. strething moe; 38 the sorption peks t (4) n 12 3 4 6 (1234) m -1 orrespon to the C=C strething virtion n C H strething virtion of quinoi ring; the peks t 13 (14) n 1292 (1299) m -1 re relte to the C=C strething virtion n C N strething virtion of enzenoi ring; the n t 11 (1116) m -1 is ue to the quinonoi unit of ope PANI. 26-32,33 The vlues outsie rket n in rket, respetively re PANI hrteristi peks prepre t ph 1. n ph 0.. The PANI peks roun 1292 (1299), 13 (14) n (4) m -1 enote there re two forms of PANI, pernigrniline n leuoemerline in the PANI-TiO 2 -HA prepre t ph 1. n ph 0.. As shown in Fig. 4,,, the peks relte to the groups of PANI lso pper in the FT-IR spetr of heterogeneous PANI-TiO 2 -HA nnotues with HNO 3, H 2 SO 4 n H 3 PO 4 tuning the ph in the preprtion, initing suessful growing of PANI. Compring to the P-TH/X/0%-HCl, the orresponing peks of PANI in the omposite ly nnotues with other i opnt tuning the ph suffer some egree of evition: those in the P-TH/X/0%-H 2 SO 4 hve tiny ifferene, wheres those in the P-TH/X/0%-H 3 PO 4 shift to lower (ph 1.) n higher wvenumers (ph 0.); those in the P-TH/1./0%-HNO 3 shift to lower wvenumers, suggesting tht ifferent intertion exists etween TiO 2 nnoprtiles n PANI. 26-32,33 Furthermore, y ompring PANI hrteristi strething ns in the rnge of 10-11 m -1 for P-TH/1./0%-Z (Fig. 4A) n P- TH/0./0%-Z (Fig. 4B), the peks of P-TH/0./0%-Z re shifte to lower wvenumer n the rtio of quinoi unit to enzenoi is out one, initing the PANI in P-TH/0./0%- Z is emerling (EM), 26 wheres in P-TH/1./0%-Z, high frtion of pernigrniline (PNA) form is present. Furthermore, s the n t 11 (1116) m -1 is srie to the quinonoi unit of ope PANI, so y ompring the pek intensity t 11 (1116) m -1 n (4), the ope egree of quinonoi unit n e lulte. From Fig. 4, the pek intensity rtio of 1116/4 for PANI-TiO 2 -HA prepre t ph 0. is higher thn tht of 11/ for PANI-TiO 2 -HA prepre t ph 1., initing higher ope egree n eletril onutivity for P- TH/0./0%-Z. To illustrte the ontrollle PANI ontent y tuning the volume rtio of ANI to TTIP, the FT-IR of heterogeneous PANI- TiO 2 -HA nnotues prepre with ifferent volume rtio of ANI to TTIP in the presene of HCl t ph 1. n 0. of the strting A Asorne Intensity (.u.) 3412 00 00 20 00 10 00 0 Wvenumer (m -1 ) 13 11 12 1292 This journl is The Royl Soiety of Chemistry [yer] Journl Nme, [yer], [vol], 00 00
, RSC Avnes Pge 6 of B Asorne Intensity (.u.) 3413 00 00 20 00 10 00 0 Wvenumer (m -1 ) 14 1116 1234 4 1299 Fig. FT-IR spetr of heterogeneous PANI-TiO 2-HA nnotues prepre y one-pot with ifferent volume rtio of ANI to TTIP t ph 1. (A) n 0. (B) of the strting sols: ) 0%, ) 1%, ) % n ) 0%. The ph of the strting sols is tune y 2M HCl solution. 2 3 sols re given in Fig.. It n lso e oserve tht with the inrese of volume rtio of ANI to TTIP, the intensity of the PANI hrteristi peks lso inreses, implying PANI ontent n e simply tune y the volume rtio of ANI to TTIP. P- TH/1./Y-Z n P-TH/0./Y-Z lso show the hrteristi ns of hlloysite, suh s the strething virtion of the inner-surfe hyroxyl groups of Al 2 OH t 3694 n 36 m -1, the eformtion virtion of the ove hyroxyl groups t 912 m -1, n the eformtions virtion of Al-O-Si n Si-O-Si t 36 n 468 m -1. 12,33,36 Interlyer or sore wter is inite y the strething virtion t 34 m -1 n the orresponing eformtion virtion t 16 m -1. The refletions of the FT-IR spetr inite tht the struture of hlloysite minerls remin unffete y the PANI-TiO 2 tretment. The protonte stte in the heterogeneous PANI-TiO 2 -HA nnotues is further stuie y UV-vis sorption spetr. UVvis spetr of P-TH/1./1%-Z n P-TH/0./1%-Z re shown in Fig. 6A n Fig. 6B, respetively. For omprison, the spetr of prent hlloysite minerls (line in Fig. 6), TiO 2 -HA nnotues prepre t ph 1. (TH/1.-HCl), TiO 2 -HA nnotues prepre t ph 0. (TH/0.-HCl) with HCl tuning the ph n P2 re lso given. It shows ll the P2, TiO 2 -HA nnotues n PANI-TiO 2 - HA sor light elow 0 nm. The min ifferene of PANI- TiO 2 -HA (P-TH/X/1%-Z) from P2 n TiO 2 -HA nnotues is it sors light giving rise to pek t 4 nm n ro pek in the rnge of 4-0 nm, respetively hrteristi of the π-π* trnsition of enzeno ring n polron-π* trnsitions of quinoi ring, 26,33 initing the presene of the PANI on the surfe of HA n two forms of PANI, pernigrniline n leuoemerline in the P-TH/X/Y-Z. Furthermore, the sorption intensity in the visile light region presents suh tren: P-TH/X/1%-HCl>P- TH/X/1%-H 2 SO 4 >P-TH/X/1%-HNO 3 >P-TH/X/1%-H 3 PO 4. An ompring to the pek strt of the ro pek in the rnge 4-0 nm of PANI-TiO 2 -HA prepre t ph 1. (Fig. 6A, mrke with sh line), the pek strt of PANI-TiO 2 -HA prepre t ph 0. re re shifte (Fig. 6B, mrke with sh line), signifying PANI form prepre t ph 0. is more loser to the EM form. 39 In 4 6 omprison to hlloysite minerl, 33,36 the sorption ttriute to rystlline TiO 2 roun 0 nm is present, whih further onfirms tht the rystlline TiO 2 is suessfully grown on the surfe of hlloysite minerls for the P-TH/1./1%-Z n P-TH/0./1%-Z smples. For P-TH/0./1%-Z, the sorption ege (Fig. 6B) shows greter re shift thn tht of P-TH/1./1%-Z ue to the presene of rutile phse (n gp energy: 3.0 ev). The ove results imply tht PANI/TiO 2 hs een suessfully grown on the surfe of hlloysite minerl n the PANI-TiO 2 -HA with HCl tuning the ph n s i opnt in the preprtion hs the strongest sorption in the visile light region. A Asorne Intensity (.u.) B Asorne Intensity (.u.) P2 Asorne Intensity (.u.) TH/1.-HCl 0 0 0 0 0 Wvelength (nm) TH/1.-HCl 0 0 0 0 0 0 0 P2 Asorne Intensity (.u.) Wvelength (nm) 0 0 0 0 0 0 0 P2 TH/0.-HCl P2 e e 0 0 0 0 0 Wvelength (nm) TH/0.-HCl Wvelength (nm) Fig. 6 UV-vis spetr of heterogeneous PANI-TiO 2-HA nnotues prepre y one-pot with 1% volume rtio of ANI to TTIP t ph 1. (A) n 0. (B) of the strting sols: ) HA, the iity is tune y ) HNO 3, ) HCl, ) H 2SO 4 n e) H 3PO 4, respetively. The omposition of P-TH/X/1%-Z is further onfirme y EDX spetr nlysis n the result is shown in Tle S1. The eletril onutivity t of P-TH/X/1%-Z shows the onutivity inreses with the erese of ph t the sme i tuning the ph n s i opnt in the preprtion. Moreover, t the sme ph, the heterogeneous PANI-TiO 2 -HA omposite nnotue with HCl tuning the ph vlue in the preprtion emonstrte the highest onutivity, followe y P-TH/X/1%- H 2 SO 4 n P-TH/X/1%-HNO 3, n P-TH/X/1%-H 3 PO 4 hs the minimum onutivity, whih re onsistent with the results of e e 6 Journl Nme, [yer], [vol], 00 00 This journl is The Royl Soiety of Chemistry [yer]
Pge 7 of RSC Avnes UV-vis. The ove results inite y simply tuning the i opnt in the preprtion, the onutivity of PANI-TiO 2 -HA omposite nnotues n e tune. 3.2. Phototlyti tivities of the heterogeneous PANI-TiO 2 - HA nnotues (P-TH/X/Y-Z) uner visile light irrition To emonstrte the influene of i opnt in the preprtion on the phototlyti tivity of the PANI-TiO 2 -HA heterorhitetures for the egrtion of orgni pollutnts, the phototlyti egrtion of rhomine B (RB) is rrie out uner visile light irrition. Furthermore, 2 mg of P2, ppm RB queous solution re use s phototlyti referenes to illustrte the phototlyti tivity of the PANI-TiO 2 -HA heterorhitetures more lerly. Photoegrtion yiel is efine s: Photoegrtion yiel = C 0 C C where C 0 is the onentrtion of ye fter 24 h sorptionesorption equilirium in the rk, C is the onentrtion fter photoegrtion of ye n C is the erese onentrtion euse of the iret photolysis. RB shows mximum sorption t out 3 nm. Totl onentrtions of the yes re etermine y the mximum sorption mesurement. The sorption pity of the PANI-TiO 2 -HA omposite nnotues prepre y one-pot in the presene of ifferent i (P-TH/X/1%-Z), P2, TH/0.-HCl n TH/1.-HCl re firstly 2 investigte. From Tle S2, it n e seen tht the introution of PANI into the omposite ly nnotue improves their sorption pities in the rk. The sorption pity of P- TH/X/1%-Z omposites nnotue with ifferent i tuning the ph in the preprtion is ifferent. The mximum sorption pity of the P-TH/0./1%-Z is oserve when H 3 PO 4 is use to tune the ph in the preprtion. The hnge in the sorption pity of P-TH/X/Y omposites with i opnt tuning the ph in the preprtion my e erive from the ifferenes in the size n nture of the opnt nion in PANI. 3 Fig. 7 shows the photoegrtion urves of RB uner visile light irrition on the P-TH/X/1%-Z, P2 n the selfegrtion of RB. It is foun tht the self-egrtion of RB is not ovious, initing the stiliztion of RB uner visile light irrition. However, in the presene of P-TH/X/1%-Z, the egrtion of RB re ovious, espeilly in the presene of P- TH/X/1%-Z with HCl tuning the ph in the preprtion n low ph vlue. PANI-TiO 2 -HA omposite nnotues prepre y onepot t ph 0. with HCl tuning the ph in the preprtion (P- TH/0./1%-HCl) hve the highest phototlyti tivity mong 4 ll the test smples, whih my e ttriute to the mixe ntse/rutile phse struture of P-TH/0./1%-HCl n the EM form of PANI. 19,33,36 In omprison, only 76.% of RB moleules for TH/0.-HCl (prepre t ph 0. with HCl tuning the ph in the preprtion n without PANI) re eompose in 6 h, initing PANI n enhne the phototlyti egrtion of RB. Wheres fter expose uner visile light irrition for 6 h, the egrtion effiieny of RB for P-TH/1./1%-HCl is higher thn tht of TH/1.-HCl, wheres in our previous report, 33 the phototlyti tivity of P-TH/1./1% with HNO 3 tuning the ph is lower thn tht of TH/1. with HNO 3 tuning the ph, implying 0 C 6 7 phototlyti effiieny will e ffete y the i opnt in the preprtion. The phototlyti egrtion effiieny of Photoegrtion Yiel (%) 0 RB 0 1 2 3 4 6 Irrition Time (h) P-TH/0./1%-HCl P-TH/0./1%-H 2 SO 4 P-TH/1./1%-H 2 SO 4 P-TH/0./1%-HNO 3 P-TH/1./1%-HCl P-TH/1./1%-HNO 3 P-TH/0./1%-H 3 PO 4 P-TH/1./1%-H 3 PO 4 Fig. 7 Comprison of photoegrtion yiel of PANI-TiO 2-HA omposite nnotues prepre y one-pot in the presene of ifferent i (P-TH/X/1%-Z) for egrtion of RB uner visile light irrition. egrtion effiieny will e ffete y the ph vlue. The phototlyti tivity of the PANI-TiO 2 -HA omposite nnotues follows the orer: P-TH/0./1%-HCl>P-TH/0./1%- H 2 SO 4 >P-TH/1./1%-H 2 SO 4 >P-TH/0./1%-HNO 3 >P- TH/1./1%-HCl>TH/0.-HCl>P-TH/1./1%-HNO 3 >TH/1.- HCl>P-TH/0./1%-H 3 PO 4 >P-TH/1./1%-H 3 PO 4 >P2. Oviously, it n e oserve the i opnt in the preprtion proess will ffet the phototlyti effiieny of P-TH/X/1%-Z. At the sme ph vlue, the phototlyti egrtion effiieny follows the sequene: P-TH/X/1%-HCl>P-TH/X/1%-H 2 SO 4 >P-TH/X/1%- HNO 3 >P-TH/X/1%-H 3 PO 4. The reson for the phenomenon is expline elow. From Tle S1n Fig. 6 (inset), it exhiits the eletril onutivity n sorption intensity in the visile light region presents suh tren: P-TH/X/1%-HCl>P-TH/X/1%- H 2 SO 4 >P-TH/X/1%-HNO 3 >P-TH/X/1%-H 3 PO 4. When the sorption intensity in the visile light region for P-TH/X/1%-Z is high, the tlyst n sor more visile light n generte more eletron-hole pirs. Furthermore, s it lso hs higher eletril onutivity n mthe well in energy level of TiO 2 n PANI, the eletrons generte from PANI uner visile light irrition n e effetively trnsferre into the CB of TiO 2. Therefore, the phototlyti tivity of P-TH/X/1%-HCl for RB is enhne ue to effiient visile light sorption n hrge seprtion. Menwhile, with the sme i tuning the ph in the preprtion proess, P-TH/X/1%-Z omposite nnotue prepre t lower ph emonstrtes higher phototlyti egrtion effiieny. Interprettion of suh negtive effet of the ph on the urrent phototlyti egrtion is very iffiult tsk euse of the possile ontriution of oth the TiO 2 n PANI in tht effet. In our previous work, 33 we hve prove y reoping P- TH/1. experiment tht the PANI reox stte plys the min ontriution to the enhne visile light tlyti egrtion effiieny of P-TH/0./Y. So we o not isuss the reson in etils here. Furthermore, phototlyti tivities of the PANI-TiO 2 -HA heterorhitetures with HCl tuning the ph n ifferent volume rtio of ANI to TTIP in the preprtion (P-TH/X/Y-HCl) for the 8 9 P2 This journl is The Royl Soiety of Chemistry [yer] Journl Nme, [yer], [vol], 00 00 7
, RSC Avnes Pge 8 of 2 3 4 egrtion of RB uner visile light irrition re lso investigte. From Fig. S6, it is ovious the visile light phototlyti tivity of P-TH/0./Y-HCl (prepre t ph 0.) is higher thn tht of P-TH/1./Y-HCl (prepre t ph 1.) on the egrtion of RB t the sme volume rtio of ANI to TTIP, whih is onsistent with the phototlyti egrtion result of the P-TH/X/1%-Z (Fig. 7). At the sme ph vlue, the phototlyti egrtion effiieny ereses with the inrese of the volume rtio of ANI to TTIP from 1% to 0% n n optimum of the sensitize effet is foun when the volume rtio of ANI to TTIP is 1%. We srie to the synergeti effet of the eletron-hole pirs proution n seprtion etween PANI n TiO 2, whih is ornt with the previous result of PANI-TiO 2 - HA prepre with HNO 3 tuning the ph vlue n FeCl 3 s ANI s oxint in the preprtion. 33 From the phototlyti results we hve gthere, it is onsistent tht the i type use for tuning the ph vlue n s i opnt, ph vlue n the volume rtio of ANI n TTIP in the preprtion will ffet the phototlyti effiieny n the highest phototlyti tivity is hieve on the PANI-TiO 2 -HA prepre t ph 0., with HCl tuning the ph n 1% volume rtio of ANI to TTIP in the preprtion (P-TH/0./1%-HCl). Furthermore, it is worth mentioning the phototlyti tivity of PANI-TiO 2- HA n e tune y tuning the onentrtion n type of i opnt in the reoping proess. To illustrte this sitution, P-TH/0./1%-HCl n P-TH/1./1%-HCl re reope with i opnt of ifferent onentrtions n vrieties. Fig. 8 shows the photoegrtion urves of RB uner visile light irrition on the P-TH/X/1%-HCl omposite nnotues fter reope with ifferent onentrtions of HCl. The reope smple is ite s P-TH/X/1%-HCl-G. G is the onentrtion of i opnt. For exmple, when the HA-TiO 2 -PANI prepre t ph 0. with 1% volume rtio of ANI to TTIP n HCl s opnt i in the preprtion (P-TH/0./1%-HCl ) is reope with 0. M HCl, it is enote s P-TH/0./1%-HCl-0. M HCl, wheres when it is reope with 0.17 M H 3 PO 4, it is enote s P- TH/0./1%-HCl-0.17 M H 3 PO 4. It shows the optiml reoping onentrtion is 0. M. After reope with HCl t the sme onentrtion, the phototlyti tivity of P-TH/0./1%-HCl is still higher thn tht of P-TH/1./1%-HCl, we ttriute this to the mixe struture of TiO 2 in P-TH/0./1%-HCl. For omprison, the phototlyti tivity of the PANI prepre t the sme iity is lso given. Although the phototlyti tivity of PANI is lower thn tht of P-TH/0./1%-HCl-G, it still emonstrtes tht the PANI prepre t 0. M HCl (PANI/0. M HCl) hs the highest phototlyti tivity, whih is ornt with the phototlyti tivity tren of P-TH/X/1%-HCl-G. In orer to fin the reltionship etween eletril onutivity n phototlyti tivity, the eletril onutivity of the pure PANI prepre t vrie iity is given (Tle S1). It n e seen the eletril onutivity inreses with the iity in the rnge of 0.0316 M (ph 1.)-2 M. Comine with the phototlyti tivity t, it n e onlue tht the enhne phototlyti tivity n e hieve t n optimum eletril onutivity of PANI. Wht is more, y reoping the P- TH/X/1%-HCl with 0.2 M H 2 SO 4 n 0.17 M H 3 PO 4, omprle to the iity of 0. M HCl, the phototlyti tivity of P-TH/X/1%-HCl-G ereses, lthough the onentrtion of i opnt n e regre s similr (Fig. S7 in ESI ), mening y tuning the type of i in the reoping proess, the phototlyti iity n e tune. Photoegrtion Yiel (%) 0 0 0 1 2 3 4 6 Irrition Time (h) P-TH/0./1%-HCl-0. M HCl P-TH/0./1%-HCl P-TH/0./1%-HCl-1 M HCl P-TH/0./1%-HCl-2 M HCl P-TH/1./1%-HCl-0. M HCl P-TH/1./1%-HCl-1 M HCl P-TH/1./1%-HCl-2 M HCl P-TH/1./1%-HCl PANI/0. M HCl PANI/1 M HCl PANI/0.-HCl PANI/1.-HCl PANI/2 M HCl Fig. 8 Comprison of photoegrtion yiel of P-TH/X/1%-HCl fter eing ope with HCl solution for egrtion of RB uner visile light 6 irrition. 7 8 9 0 3.3. Mehnism of the ifferent visile phototlyti tivity of the heterogeneous PANI-TiO 2 -HA nnotues y tuning the i opnt in the preprtion. On the sis of the results of phototlyti tests, it shows the heterogeneous PANI-TiO 2 -HA omposite nnotues with ifferent i tuning the ph n s i opnt in the preprtion hve ifferent visile light phototlyti tivity: P-TH/X/1%- HCl emonstrtes the highest phototlyti tivity, followe y P-TH/X/1%-H 2 SO 4 n P-TH/X/1%-HNO 3, n P-TH/X/1%- H 3 PO 4 hs the minimum phototlyti tivity t the sme ph vlue. An UV-vis n eletril onutivity test for the light sorption in the visile light region n eletril onutivity lso present similr tren. It is reporte tht TiO 2 n PANI re mthe well in energy level: the onution n (CB) position of TiO 2 is lower thn the LUMO of PANI, so the former n t s sink for the photogenerte eletrons in the hyri phototlysts; the vlene n (VB) position of TiO 2 is lower thn the HOMO of PANI, so the lter n t s n eptor for the photogenerte holes in the hyri phototlysts. 28-,33 Therefore, when the PANI-TiO 2 -HA omposite nnotue with enhne visile light sorption n eletril onutivity is illuminte uner visile light, more visile light is sore n more eletron-hole pirs is generte, the eletrons generte from PANI n e effetively trnsferre into the CB of TiO 2, while some positive ron rils in PANI re forme, s well s in ye-sensitize TiO 2 system. These positive ron rils my e reue y n eletron from orgni pollutnts or wter, or ret with oxygen to generte tive speies (hyrogen ril, singlet/triplet oxygen) whih re ple of egring orgni pollutnts. So herein, effetive visile light sorption, reuing the reomintion proility n mking hrge seprtion more effiient le to higher phototlyti tivity with the heterogeneous PANI-TiO 2 -HA nnotues prepre with HCl tuning the ph in the preprtion. 4. Conlusions We hve propose file metho to synthesize heterogeneous 8 Journl Nme, [yer], [vol], 00 00 This journl is The Royl Soiety of Chemistry [yer]
Pge 9 of RSC Avnes PANI-rystlline TiO 2 -HA nnotues with enhne visile light phototlyti tivity y tuning the i opnt in the preprtion. By simple justment of the iity of the TiO 2 sol t 6 C, PANI-rystlline TiO 2 -HA omposite nnotues ompose of ntse, mixe-phse TiO 2 n ifferent PANI reox stte n e proue. The egrtion of RB in n queous solution uner visile light irrition is rrie out to evlute the phototlyti tivity of the resulting omposite phototlysts. It shows phototlyti tivity will e ffete y the type of i opnt, ph vlue n the volume rtio of ANI to TTIP in the preprtion n the highest phototlyti tivity is hieve with the omposite phototlysts prepre with HCl tuning the iity t ph 0. n 1% volume rtio of ANI n TTIP (P-TH/0./1%-HCl). This n e ttriute to the effetive visile light sorption n hrge seprtion. Furthermore, reoping P-TH/0./1%-HCl with ifferent onentrtion of HCl n i opnt (H 2 SO 4 n H 3 PO 4 ) emonstrtes reoping with 0. M HCl hs the highest phototlyti tivity n its phototlyti tivity ereses when reope with H 2 SO 4 n H 3 PO 4, initing y tuning the onentrtion n type of i opnt in the reoping proess, the phototlyti iity n e tune. Aknowlegment The uthors grtefully knowlege the finnil support of the 2 Ntionl Nturl Siene Fountion of Chin (Nos. 623, 91), the Applie Bsi Fountion of Yunnn Provine (No. 13FB002), the Eution Reserh Fountion of Yunnn Provine (Nos. 13Y361, Y2), the Reserh Fountion of Yunnn University (No. 09B06Q) n Bkone Teher Trining Progrm of Yunnn University (No. XT4103). Notes n referenes Deprtment of Applie Chemistry, Key Lortory of Meiinl Chemistry for Nturl Resoure, Ministry of Eution, Shool of Chemil Siene n Tehnology, Yunnn University, Kunming 6091, 3 Chin. Fx: +86 871 63 67; Tel: +86 871 63 67; E-mil: lip8@is..n Eletroni Supplementry Informtion (ESI) ville: SEM n TEM imges, XRD, XPS n EDX of the hlloysite (HA) minerls (Fig. S1-Fig. S4), FT-IR spetr of heterogeneous P-TH/X/1%-Z (Fig. S), mss rtio of PANI to TiO 2 n onutivity of P-TH/X/Y-Z (Tle S1), the sorption rtio of P-TH/X/1%-Z for RB (Tle S2), photoegrtion yiel of P-TH/X/Y-HCl (Fig. S6) n P-TH/X/1%-HCl fter eing ope with 0. M HCl, 0.2 M H 2SO 4 n 0.17 M H 3PO 4 solution (Fig. S7). See DOI:.39/000000x 4 1 T. S. Wu, K. X. Wng, G. D. Li, S. Y. Sun, J. Sun n J. S. Chen, ACS Appl. Mter. Interfes,, 2, 44. 2 G. K. Zhng, X. M. Ding, F. S. He, X. Y. Yu, J. Zhou, Y. J. Hu n J. W. Xie, Lngmuir, 08, 24, 26. 3 G. Zhng, Y. Go, Y. Zhng n Y. Guo, Environ. Si. Tehnol.,, 44, 6384. 4 P. Arn, R. Kun, M. Angeles Mrtín-Luengo, S. Letïef, I. Dékány n E. Ruiz-Hitzky, Chem. Mter., 08,, 84. A. Roríguez, G. Ovejero, M. Mestnz n J. Grí, In. Eng. Chem. Res.,, 49, 37. 6 J. Liu, D. Mengqin, Z. Shengli n Y. Yinghun, Appl. Cly Si., 09, 43, 6. 7 C. Li, J. Wng, S. Feng n Z. Liu, Chin. J. Chem., 14, 32, 99. 8 S. Brrientos-Rmírez, E. V. Rmos-Fernánez, J. Silvestre-Alero, A. Sepúlve-Esrino, M. M. Pstor-Bls n A. González- Montiel, Miroporous Mesoporous Mter., 09, 1, 132. 9 E. Aullyev, K. Skkir, K. Okmoto, W. Wey, K. Arig n Y. Lvov, ACS Appl. Mter. Interfes, 11, 3,. L. Wng, J. Chen, L. Ge, Z. Zhu n V. Ruolph, Energy Fuels, 11, 2, 38. 6 11 J. Ling, B. Dong, S. Ding, C. Li, B. Q. Li, J. Li n G. Yng, J. Mter. Chem. A, 14, 2, 11299. 12 C. Li, J. Wng, X.Luo n S. Ding, J. Colloi Interfe Si., 14, 4, 1. 13 P. Yun, P. D. Southon, Z. Liu, M. E. R. Green, J. M. Hook, S. J. Antill n C. J. Kepert, J. Phys. Chem. C, 08, 112, 742. 14 C. Li, J. Liu, X. Qu, B. Guo n Z. Yng, J. Appl. Polym. Si., 08, 1, 3638. W. O. Yh, A. Tkhr n Y. M. Lvov, J. Am. Chem. So., 12, 134, 183. 7 16 G. Cvllro, G. Lzzr n S. Milioto, Lngmuir, 11, 27, 18. 17 V. Vergro, E. Aullyev, Y. M. Lvov, A. Zeitoun, R. Cingolni, R. Rinli n S. Leportti, Biomromoleules,, 11, 8. 18 B. Wu, H. H. Hng n X. W. Lou, Av. Mter., 12, 24, 267. 19 J. Zhng, Q. Xu, Z. Feng, M. Li n C. Li, Angew. Chem., Int. E., 08, 1, 17. Y. Lio, W. Que, Q. Ji, Y. He, J. Zhng n P. Zhong, J. Mter. Chem., 12, 22, 7937. 21 R. Ashi, T. Morikw, T. Ohwki n K. Aoki, Y. Tg, Siene, 01, 293, 269. 8 22 Q. Dong, H. Yu, Z. Jio, G. Lu n Y. Bi, RSC Av., 14, 4, 9114. 23 J. Tng, D. Li, Z. Feng, Z. Tn n B. Ou, RSC Av., 14, 4, 21. 24 C. Xue, T. Wng, G. Yng, B. Yng n S. Ding, J. Mter. Chem. A, 14, 2, 7674. 2 H. Zhng, R. Zong, J. Zho, Y. Zhu, Environ. Si. Tehnol., 08, 42, 33. 26 E. T. Kng, K. G. Neoh n K. L. Tn, Prog. Polym. Si., 1998, 23, 211. 27 Y. Zhu, D. Hu, M. X. Wn, L. Jing n Y. Wei, Av. Mter., 07, 21, 92. 9 28 R. Rmkrishnn, J. D. Suh n V. L. Reen, RSC Avnes, 12, 2, 6228. 29 M. A. Slem, A. F. Al-Ghonemiy n A. B. Zki, Appl. Ctl., B, 09, 91, 9. S. Min, F. Wng n Y. Hn, J. Mter. Si., 07, 42, 9966. 0 1 1 1 31 H. M, Y. Li, S. Yng, F. Co, J. Gong n Y. Deng, J. Phys. Chem. C,, 114, 9264. 32 O. Aulrzzq, S. Bouro, V. Sini, V. G. Biri, E. Dervishi,T. Viswnthn, Z. A. Nim n A. S. Biris, Energy Tehnol., 13, 1, 463. 33 C. Li, J. Wng, H. Guo n S. Ding, J. Colloi Interfe Si.,, 48, 1. 34 D. Ppoulis, S. Komrneni, A. Nikolopoulou, P. Tsolis-Ktgs, D. Pngiotrs, H. G. Knes, P. Zhng, S. Yin, T. Sto n H. Ktsuki, Appl. Cly Si.,,, 118. 3 D. Ppoulis, S. Komrneni, D. Pngiotrs, E. Stthtos, D. Toli, K. C. Christoforiis, M. Fernánez-Grie, H. Li, S. Yin, T. Sto n H. Ktsuki, Appl. Ctl., B, 13, 132, 416. 36 C. Li, J. Wng, S. Feng, Z.Yng n S. Ding, J. Mter. Chem. A, 13, 1, 4. 37 E. A. Brringer n H. K. Bowen, Lngmuir, 198, 1, 4. 38 Z. Niu, Z. Yng, Z. Hu, Y. Lu n C. C. Hn, Av. Funt. Mter. 03, 13, 949. 39 J. E. Aluquerque, L. H. C. Mttoso, D. T. Blogh, R. M. Fri, J. G. Msters n A. G. MDirmi, Synth. Met. 00, 113, 19. This journl is The Royl Soiety of Chemistry [yer] Journl Nme, [yer], [vol], 00 00 9
RSC Avnes Pge of Grphil Astrt One-imensionl heterogeneous polyniline-rystlline TiO 2 -hlloysite nnotues with enhne visile-light phototlyti tivity were hieve y tuning the i opnt in the preprtion t low temperture Photoegrtion Yiel (%) 0 0 1 2 3 4 6 Irrition Time (h) P-TH/0./1%-HCl P-TH/0./1%-H 2 SO 4 P-TH/1./1%-H 2 SO 4 P-TH/0./1%-HNO 3 P-TH/1./1%-HCl P-TH/1./1%-HNO 3 P-TH/0./1%-H 3 PO 4 P-TH/1./1%-H 3 PO 4 P2 RB