doi:1.138/nture1241 Figure S1., TEM imge of gold nnoprtiles.,, Chemil strutures of nioni itrte nd tioni polyurethne opolymer, respetively. Comment: Gold nnoprtiles were synthesized ording to slightly modified literture proedure. 1 The use of itrte for olloidl stiliztion of gold nnoprtiles is expeted to ring out miniml rriers for hrge trnsport etween nnoprtiles, whih is not the se of gold nnoprtiles with stilizers with long liphti hins. As suh, ondutivities of free-stnding LBL films using oleylmines-stilized gold nnoprtiles nd 1,6-hexnedithiol-stilized gold nnoprtiles were 2 x 1-2 S m -1, 2 nd 3.7 x 1-2 S m -1, 3 whih were t lest 1 5 times lower thn tht of 5 x VAF omposite. Tle S1 elow shows more ondutivity dt of LBL films from gold nnoprtiles. Tle S1. Previous ses of LBL films from gold nnoprtiles nd their ondutivity. Dimeter of gold nnoprtiles (nm) Stilizer 5 sodium orohydride Counter polyeletrolyte poly(dillyldimethyl mmonium hloride) 13 itrte poly(dillyldimethyl mmonium hloride) Thikness of film (nm) Condutivity (S m -1 ) (referene) 6 2 x 1 5 (4) 6 1.8 x 1 5 (5) 2.5 itrte ethnedithiol 52 2.5 x 1 5 (6) 2.5 itrte ethylenedimine 52 2 x 1 5 (7) -2 (2) 9 oleylmine 1,9-nonnedithiol 6 2 x 1-2 (3) 1 1,6-hexnedithiol lknedithiol 26 3.7 x 1 WWW.NATURE.COM/NATURE 1
RESEARCH SUPPLEMENTARY INFORMATION Figure S2., Dependene of thikness of the (PU/NP) n film on the numer of the deposition yles. Polyurethne (3P, 4P, 5P ) nd gold nnoprtiles (3A, 4A, 5A ) lyers with the sme numer orrespond to one deposition yle. Thikness hnge ws mesured y ellipsometry s the LBL film ws deposited on silion wfer. Thikness of eh lyer ws verged on the sis of three independent mesurements. Averge thikness inrements for polyurethne nd gold nnoprtiles lyers re 1.89 nm nd 2.4 nm, respetively., UV-Vis sorne spetr mesured every 5 th lyer pirs of LBL ssemlies. The multilyers were formed on oth sides of glss sustrte. The shift of the plsmon pek from 515 nm (free gold nnoprtiles) to 65-66 nm for LBL films is inditive of strong plsmoni oupling nd nnoprtiles proximity to eh other, whih is enefiil for effiient hrge trnsport etween nnoprtiles. Figure S3. Therml grvimetri nlysis (TGA) of pure gold, pure polyurethne, nd single freestnding, 1x, LBL nd VAF films with different gold ontents. The vol% given in prentheses refers to V f of gold in eh film nd 21.7 vol% is equl to 87.7 wt%. 2 WWW.NATURE.COM/NATURE
RESEARCH Figure S4. Differentil snning lorimetry (DSC) for pure polyurethne, LBL films, VAF films, nd pure gold. Nnoprtile ontents of omposites re given in prentheses nd refer to V f of gold in eh film. WWW.NATURE.COM/NATURE 3
RESEARCH SUPPLEMENTARY INFORMATION Figure S5. Idelized shemtis of well-dispersed nnoprtiles in LBL nd VAF omposites with distriuted rndom ggregtes (numer of prtiles is sme for oth ses nd spes re filled with polymers in the lttie) in 2D ross-setionl grid rry with peroltion pthwys to nerest neighors of nnoprtiles. Theoretil vlues of V volume frtions, whih refleted site peroltion proility nd filling ftor together, for nnoprtiles omposite ssuming tht () one nnoprtile tkes ple one lttie spot nd () luster is onneted only with nerest neighors, for simple ui lttie, ody-entered ui lttie, nd fe-entered ui lttie re.162,.163, nd.144, respetively 8,9. Figure S6. High-voltge eletron mirosopy (HVEM) imges of 1 x VAF. Imging ws performed on the ruptured point. The speimens were prepred y using FIB. 4 WWW.NATURE.COM/NATURE
RESEARCH. d Figure S7.,, SEM imges of surfes of 5 x LBL nd 5 x VAF in relxed stte fter five onseutive strethes to 11% nd 2%, respetively., d, Stress-strin urves for 5 x LBL nd 5 x VAF fter speifi strething yles with ε=11% nd 2%, respetively. WWW.NATURE.COM/NATURE 5
RESEARCH SUPPLEMENTARY INFORMATION d I(q) (. u.) 1.E+4 1 4 1.E+3 1 3 1.E+2 1 2 1.E+1 1 1 1 LBL x LBL 1, Cyled 1 LBL x LBL % Pristine Strined 1 VAF AL x VAF 1, 1, Cyled Cyled 1 AL x VAF % Pristine Strined 1.E+ 1.1.5.9.13.17 1.E-1 1-1 q (Å -1 ) Figure S8. Condutivity nd smll-ngle X-ry sttering (SAXS) dt fter reurrent strething yles., Illustrtion of the ondutivity mesurements y two proe method in different diretions fter 1, strething yles with ε=5%. 1: prllel to the tensile diretion efore strin yles, 2: perpendiulr to the tensile diretion efore strin yles, 3: prllel to the tensile diretion fter strin yles, nd 4: perpendiulr to tensile diretion fter strin yles., Resistne dt y two-proe method in the diretions nd reurrent strething yles for 1 x LBL nd 1 x VAF, respetively., SAXS em imges of 1, yled 1 x LBL nd 1xVAF films. Smples were horizntlly pled for mesurements. d, Plots of sttering intensity, I(q), in respet to sttering vetor, q, for 1 x LBL nd 1 x VAF. SAXS mesurements were performed on the enter of the films. 6 WWW.NATURE.COM/NATURE
RESEARCH y = 1.4957x + 5.6935 R² =.9882 4 3 3 log σ 2 log σ 2 1 y = 1.173x + 4.3448 R² =.9148 1-5 -4-3 -2-1 log (V f V ) -1-3 -2-1 log (V f V ) d 1.E+4 1.E+4 σ (S m -1 ) 1.E+2 σ (S m -1 ) 1.E+2 1xLBL x LBL 1xVAF x VAF LBL y Eq. 1 1.E+ 15 2 25 V f (vol%) VAF y Eq. 1 1.E+ 15 2 25 V f (vol%) Figure S9. Experimentl dependene of σ on V f nd its lineriztion ording to the lssil power-lw reltion of 3D peroltion theory.,, Log plots of σ in respet to log(v f V ) with liner fit s desried s Eq. 1 in the min text for 1 x LBL nd 1 x VAF, respetively., d, Comprison of lulted ondutivities nd tul dt of 1 x LBL nd 1 x VAF for unstrined omposites, respetively 1. In order to desrie the ehvior of our nnoprtile omposites in terms of the power-lw of peroltion theory (Eq. 1), the ritil exponents, s, orresponding to oth mterils were determined to e s LBL =1.5 nd s VAF =1.17 from the slopes of dependenies in Fig. S9 nd S9, respetively. The pplition of the lssil peroltion theory to VAF omposite system is impeded y the fundmentl ssumption of individul filler prtiles to e homogeneously dispersed in the mtrix tht Eq.1 is sed on. Despite the suessful lineriztion in the log-log plot in Fig. S9, further pplition of the theory is impeded y signifint gglomertion of gold prtiles lerly visile in Fig. 2k tht result in the distint mismth of experimentl nd predited vlues in Fig. S9d. WWW.NATURE.COM/NATURE 7
RESEARCH SUPPLEMENTARY INFORMATION Comments to the method of Chun et l. (ondutivity to the unixil strin) The method used y Chun et l., whih desried ondutivity of omposite to the unixil strin y onverting V f to ε nd Poisson s rtio (ν), σ = σ V V (Eq. 1) ( f )s Vgold V f ( ε ) = V ( ε ) 2 V ( ε) = L ( ε) w ( ε) t ( ε) 2 2 2 2 L ( ε) = L ( ε + 1) 2 1 w ( ε) = w (1 ν ε) 2 1 t ( ε) = t (1 ν ε) 2 1 ( ) w1 w2 νw ε = w ε 1 1 t1 t2 νt ( ε) = t ε t w ouldn t perfetly desrie tul deformtion of omposite euse onstnt ν t some point (. ε=4%) ws expeted to mke the volume derese nd negtive, whih is not physil. The ove method nd Eq. 2 in the min text hd sme pplile rnge of strin up to. 11%. 8 WWW.NATURE.COM/NATURE
RESEARCH σ Hopping A = σ exp( ) 1/4 T σ Tunneling B = σ exp( ) 1/2 T d e f Figure S1. Chrge trnsport in polyurethne-nnoprtile nnoomposites.,, Equtions for vrile-rnge hopping nd tunneling mehnisms, respetively 11,12., d, Plots of ln σ vs T -1/4 nd T -1/2 from dt points of 1 x LBL film (Fig. 2F), respetively. e, f, Plots of ln σ vs T -1/4 nd T - 1/2 from dt points of 1 x VAF film (Fig. 2F), respetively. Three different ondution mehnisms re possile etween neighoring gold nnoprtiles: () diret ontt; () vrile-rnge hopping nd () tunneling. The reltive ontriution of hopping nd tunneling mehnisms depends on the shpe of the rrier, the seprtion of the sites nd therml energy 13. Dependene of ondutivity on temperture provides relile riterion y whih ondution mehnism tht domintes the smples n e unveiled. Fitting the equtions for vrile-rnge hopping nd tunneling ondution mehnism demonstrte tht eletron trnsfer mehnism in LBL nd VAF strethle ondutors is governed neither y hopping nor y tunneling: plots of ln σ vs T -1/4 nd T -1/2 drwn from dt points from Fig. 2f with equtions in Fig. S1 nd S1 did not onform to expeted liner dependene. WWW.NATURE.COM/NATURE 9
RESEARCH SUPPLEMENTARY INFORMATION Figure S11., Eletron moility nd, Crrier onentrtion of 1 x LBL nd 1 x VAF determined y the Hll effet mesurements. 1 WWW.NATURE.COM/NATURE
RESEARCH Figure S12. Photogrphi imges for the set up used in mesuring ondutivity nd lulting ν to tensile strin dependene with four-proe method exemplified for 1 x VAF. Geometril terms re speified. The four proes were pled on the smple s shown in () nd (). Chnge of resistne on the multimeter nd hnge of strin on the disply of tensile mhine (just elow the multimeter) were video reorded together s shown in (). Smple eing strethed ws photogrphed to see hnge of length nd width (one photogrph ws tken every seond) to lulte thikness of smple t eh photogrph under the ssumption of no volume hnge. Video reorded resistne, strin, nd thikness dt were used to lulte dt points for the ondutivity vlues reported in the pper. Clulted Poisson s rtios were s follows: ν LBL, thikness =.26, nd ν LBL, width =.14, ν VAF, thikness =.39, nd ν VAF, width =.12. WWW.NATURE.COM/NATURE 11
RESEARCH SUPPLEMENTARY INFORMATION 1 x LBL 1 x LBL.5 1.2 tn δ.4.3.2.1 1 2 3 4 6 1 16 25 4 63.2 V, 26 C V, 26 C V, 2 C Condition Storge modulus (GP).9.6.3 1 2 3 4 6 1 16 25 4 63 V, V, R.T. 2 C V, V, 2826 C C.2.2 V, V, 28 C 26 C Condition Frequeny (Hz) Frequeny (Hz) d.5 1 x VAF e 1.2 1 x VAF tn δ.4.3.2.1 1 2 3 4 6 1 16 25 4 63.2 V, 28 C V, 28 C V, R.T. 2 C Condition Storge modulus (GP).9.6.3 1 2 3 4 6 1 16 25 4 63 V, 2 C V, 28 C.2 V, 28 C Condition Frequeny (Hz) Frequeny (Hz) Figure S13. Dmping properties of polyurethne-nnoprtile nnoomposites with V t the relevnt tempertures (purple rs) under frequeny rnges from 1-9 Hz with referene onditions with nd.2 V., Experimentl setup for mesuring dmping properties with voltge.,, dmping prmeter tn δ nd storge modulus of 1 x LBL, respetively. d, e, dmping prmeter tn δ nd storge modulus of 1 x VAF, respetively. When.2 V ws pplied, temperture of omposites inresed to 26 C nd 28 C for 1 x LBL nd 1 x VAF, respetively. To show tht hnge of dmping properties t the low frequeny region were minly used y pplied voltge, those with no voltge nd t the temperture of 26 C for 1 x LBL nd 28 C for 1 x VAF were mesured. Dt showed pplied smll voltge signifintly tuned dmping properties espeilly t the low frequeny region while only temperture ouldn t tune the dmping properties t speifi frequeny rnges insted it slightly ffeted over the entire frequeny region. 12 WWW.NATURE.COM/NATURE
RESEARCH REFERENCES 1 Turkevih, J., Stevenson, P. C. & Hillier, J. A Study of the Nuletion nd Growth Proesses in the Synthesis of Colloidl Gold. Disuss Frdy So, 55-75 (1951). 2 Olihwer, N., Lei, E. W., Hlfr, A. H., Petrov, A. & Vossmeyer, T. Cross-Linked Gold Nnoprtiles on Polyethylene: Resistive Responses to Tensile Strin nd Vpors. ACS Appl Mter Inter 4, 6151-6161 (212). 3 Joseph, Y. et l. Self-ssemled gold nnoprtile/lknedithiol films: Preprtion, eletron mirosopy, XPS-nlysis, hrge trnsport, nd vpor-sensing properties. J Phys Chem B 17, 746-7413 (23). 4 Liu, Y. J., Wng, Y. X. & Clus, R. O. Lyer-y-lyer ioni self-ssemly of Au olloids into multilyer thin-films with ulk metl ondutivity. Chem Phys Lett 298, 315-319 (1998). 5 Kumlngdudsn, P., Tuntrnont, A., Dus, S. T. & Dus, L. Frition of miroeletrodes using flow lyer-y-lyer self ssemly of gold nnoprtiles. Superlttie Mirost 52, 143-151 (212). 6 Bsrir, F. & Yoon, T. H. Sonition-ssisted lyer-y-lyer deposition of gold nnoprtiles for highly ondutive gold ptterns. Ultrson Sonohem 19, 621-626 (212). 7 Bsrir, F. & Yoon, T. H. Preprtion of highly ondutive gold ptterns on polyimide vi shking-ssisted lyer-y-lyer deposition of gold nnoprtiles. Colloid Surfe A 393, 27-31 (212). 8 Stuffer, D. & Ahrony, A. Introdution to peroltion theory. Rev., 2nd edn, (Tylor & Frnis, 1994). 9 Sher, H. & Zllen, R. Critil Density in Peroltion Proesses. J Chem Phys 53, 3759-3761 (197). 1 Li, J. & Kim, J.-K. Peroltion threshold of onduting polymer omposites ontining 3D rndomly distriuted grphite nnopltelets. Compos Si Tehnol 67, 2114-212 (27). 11 Mott, N. F. Condution in non-rystlline mterils. Philosophil Mgzine 19, 835-852 (1969). 12 M, Y. G., Liu, H. J. & Ong, C. K. Eletron trnsport properties in CoAlO omposite ntidot rrys. Europhys Lett 76, 1144-115 (26). 13 Ko, K.-C. & Hwng, W. Eletril trnsport in solids : with prtiulr referene to orgni semiondutors. 1st edn, (Pergmon Press, 1981). WWW.NATURE.COM/NATURE 13