side@hacettepe.edu.tr IAEA Regional Training Course , 8-12 November 2010 Nano structured materials Multilayer Films, Polycrystalline, Nanocomposites, Patterned structures, Bulk structures, Liquid crystals, Biological samples, Fractals, Gels, and etc. “When scientists have learned how to control the arrangment of matter at a very small scale, they will see materials take an enormously richer variety of properties” Richard Feynman (1959) 1013 photon/s/mm2 High flux, more intensed x-rays 108 photon/s/mm2 Widely used flux, conventional x-rays Different formed aggregats can be investigated Diluted -I Lamellar Densed -I The other densed systems Diluted -II Densed -II 03.01 -20.07 2009 SWAXS (Small and Wide Angle X-Ray Scattering) Analizleri -k q k’ I (Scattering intensity) I (Scattering intensity) 2ө k q, X-ray scattering vector q= k´-k |q|=2 k sin q= 4 sin / q (Å-1) q (Å-1) A(q) = Ae (r) exp(-iq.r) dr = [A(q)/Ae] exp(iq.r) dq Scattered wave amplitude Radial electron density I(q)= |A(q)|2 = Ae2 | (r) exp(-iq.r) dr |2 = P(r) exp(-iq.r) dr Scattered wave intensity Reciprocal space (r) Fourier T. P(r) Fourier T. = (u+r) (u) du = I(q) exp(iq.r) dq Distance distribution function Real space The followed process to determine structures is used Measuring data Determining of structural parameters R, M, V etc. In addition to SAXS technique other techniques are: SANS scattering) XAFS Defining model structure in real space and for this purpose using other collaborative techniques Construction of the model in q space and fitting of the experimental and theoretical results ( Small angle neutron (X-ray Absorption Fine structure), XRD (X-ray Diff.) and Microscopy techniques. More sensitive and recordable structural results can be obtained by this combination . 1. region 2. region 3. region I Experimental curve I(q) = N [F(q)]2 S(q) q P Particle Form Factor P(q)= F(q) 2 F(q)= 3V (1-2) [ sin(qR) – qR cos(qR) ] / (qR)3 S I(q) = N [P(q)] q Diluted identical I(q) = N1 [P1(q)]+ N2 [P2(q)] Solution Structure Factor Dilute two type particles It defines the relatonship between the positions of the particles I(q) = N g(R) [P(q)] dR Dilute polydisperse q WAXS sample: lactose powder sample-detector distance: 29.5 cm active length of detector ~ 5 cm 1024 pixels 50 µm/pixel 2~18° 4.8 Å Calibration of the q-scale (WAXS) with p-Br-BA powder: 2~26° 3.2Å SAXS Calibration of the qscale (SAXS) with Ag-behenate powder: Lamellar d-spacing: d = 58.38 Å center of incident primary beam 2665 Å 800 Å Primary beam (attenuated) FWHM ~ 350 µm sample: Lupolen sample-detector distance: 28 cm active length of detector ~ 5 cm 1024 pixels 50 µm/pixel 2~8° 11Å Diluted systems-I Protein or polymer solutions, etc. First determined structural information - Radius of gyration, - Mass, volume and shape Guinier region I ln I I(q) =I(0) exp(-R2q2/3) 1/R . q(nm-1) Guinier line tan = -R2/3 q2 Spherical nano crystals embeded SiO2 Nanocrystals glass Nanocrystals Noncrystallized aggregations Before cystallization R<R0 R=R0 Different electron densities After the cryst. R<R0 Radius of gyration ____________ R= (a2+b2+c2)/5 Elipsoid a,b,c R2 = r 2 (r) d3r (r) d3r elipsoid axes Guinier law (q0) ____ R= (3/5) r = 0.77 r Sphere r, radius I(q)q4 Porod law (q) lim I(q) q4 = constant Porod region lim I(q)= 2 (1-2)2 S / q4 S, surface area q (Å-1) Kratky plots I.q2 (nm) -2 Invariant Q Q = V <2> Fluctuation in the electron densities V Total volume causing the scattering Sample: Amorph and crystalline regions in the structure Two phase polymers Q = V (k-a)2 ak k , a electron densities of the phases q (nm) -1 Kratky plots with Porod law a , k volume fractions of the phases Lamellar Structures I The positions of Bragg peaks for h = 1, 2, 3 give the lamellar distance (1/d) q If we look through the perpendicular direction of the lamelar structure, we may define crystallographic order in SAXS range. In this case, by using scattering intensity ratios and peak positions, some scattering rules ( for hexagonal, cubic etc.) controlled and compaired to obtain the real phases. 80 80 60 60 60 40 40 40 20 20 20 0 0 .0 I(q ) 80 I( q ) I(q ) Some ordered cubic morphologies 0 .1 0 .2 0 .3 0 .4 0 .5 0 0 .0 P-surface 0 .2 0 .3 0 .4 0 .5 0 0 .0 Pn3 m D-surface 0 .1 0 .2 0 .3 0 .4 0 .5 q q q Im3m 0 .1 Ia3d G-surface Figures, H. Amenitsch, SR School-ICTP Hegzagonal struct. Lamellar fluid ? I. III. II. lam hex According to the observed q ratios (1) Periodic structure: 1 : 2 : 3 : 4…; (2) Cubic: 1: 2 : 3 : 4 : 5 …. ; (3) Hegzagonal 1: 3 : 4 : 7 : 9 : 12 PS-b-PEO Co-polymer phase transition Photonic crystals Interplanar distance is increasing with increasing temperature Blue Heating Light blue Spin-cap (rotating capillary) 300 s / Frame Sample rotation enhances signal-noise ratio SAXS 300 s / Frame 45 ° WAXS SWAXS scanning of phase transitions 20° www.hecus.at 23 ln I(q) ln I(q) 0.05 0.10 0.15 0.05 q (Å-1) ln I(q) ln I(q) 0.10 0.15 q (Å-1) Guinier Slope Porod 0.05 0.10 0.15 q (Å-1) -2.50 -2.00 -1.50 -1.00 ln q Shape reconstruction A serial research on pH and temperature dependent-water soluble diblock copolymers [2-(dietilamino) etil metakrilat]-b-[2-(dimetilamino) etil metakrilat] (DEAn-b-DMAm) Hydrophillic(repulsion) DEAn-b-DMAm diblock copoylmers are stable (n/m=1/2) in misellar forms at 23C ve pH=7,7. size distributions are narrow and forms are spherical. For T=22,0-25,5C, pH=7,6-8,0 and n/m=0,25-0,73 values, misel numbers per unit volume, misel sizes, shell thickness, core radius and densities have been determined by SAXS analysis. Hydrophobic (attraction) shell core t = thicknes of the shell t Rc = core radius Rs = t + Rc Rc ρc ρc = core electron density ρs ρç Rs ρs = shell electtron density ρç = solution electron density pH controls charge level and if the misel size increase s, electrostatic repulsion becomes effective. Volume hight and base area of the cone were determined beside of packing parameter Cubic structures occured by DNA and peptid connected spherical gold nanoparticles 13 nm Y9,Y10 Y11, ……, Y20 Y9,Y10 liquid paraffin, non-ionic surfactants (Brij 72 and Brij 721P) and/or pure water H3 Formulation Liquid Parafin (%w/w) Brij 721 P/ Brij 72 (3/1) (%w/w) H2O (%) A3 H3 L2 F1 70 6 40 30 30 31 10 70 63 50 AFM View TEM View [D.I. Svergun, Biophysics J. 1999, 76, 2879-2886] Ferroelectric thin films, P.C. Mclntyre Res. Group, Stanford Nonhomogen dielect. (sculptured) thinfilm, STF, A. Lakhtakia, Penn State Photovoltaics, H. Kurz, Inst. of Semiconductor Elect. Germany SrGa2S4:Ce thin-film, K. Tanaka, NHK Lab. Japan Multilayered Al-Si Porous thin films, C. Orilall , Cornel Univ. Ultra-thin solid oxide fuel cell, F.B. Prinz ,RPL Stanford Engineering n+ Ga As Sample I (7) 20 mol% 400 Å 65 Å 400 Å 21 mol% 55 Å 24 55 24 45 27 400 Å n Ga As 400 Å Sample II (8) i Al Ga As n+ Ga As 45 30 40 33 GaAs , a= 5.65 Å, AlGaAs, a= 5.66 Å, 35 = 5.32 g/cm3 = 3,76 g/cm3 dac da dc k is decay constant (interfacial area) for a two phase system. It depends on the total inner surface (S) and the mean-square electron density fluctuations Q invariant It has the dimention of a resprocal volume Volume fractions Total irradiated volume d(Å)Sample I (7) d(Å) Sample II (8) 330.00 202.70 184.73 116.40 136.59 80.24 104.70 61.00 82.67 70.59 60.41 52.79 49.87 42.16 37.40 30.35 Mean sizes of the planar aggregations in the content of the sample I and II are 198.09 and 121.67 Å , respectively. R( Å) Sample I R( Å) Sample II 5.32 30.77 56.41 79.48 100.02 125.64 184.63 217.94 258.97 317.95 371.80 425.64 453.85 6.44 35.42 62.79 83.72 122.36 161.10 194.81 223.79 262.43 281.75 Summary Analysis of total scattering gives valuable insight in the structureproperties relationship High resolution instruments open the door to medium-range order investigations Usage of collaborative techniques always preferable to reach more detailed knowledge. GISAXS 0.2- 0.6 ⁰ 2. BP Düzgün yönelmiş tabakalar LS 1. BP İzotropik lipozom SB + PB f W- tarama i www.hecus.at 42 SAXS ile algılanan nano-oluşumlar (1-100 nm) WAXS ile algılanan nano-oluşum iç yapıları ( 1-10 Å) Lc : correlation Lc distances SAXS ile elde edilen bilgiler: *Kesikli çizgilerle gösterilen elektron yoğunluk farklarının yüksek olduğu nano oluşumların şekli/şekilleri * Nano-oluşumların ortalama büyüklükleri *Nano-oluşumlar arası ortalama uzaklık ve uzaklık dağılımları *Birim hacimdeki nano-oluşum sayıları v.b. bilgiler. Plaka formu için yapısal bilgiler İkili uzaklık dağılımları Polimer içine dağılarak bulundukları genel malzeme ortamının elektron yoğunluğunu artıran moleküler saçaklanmalar Bütün verinin GNOM programı ile arıtılması F o lie :S A X S 6 .d o c F o u r ie r T r a n s fo r m a tio n o f P a r tic le S c a tte r in g C u r v e I h 4 0 p r sin ( h r ) dr hr I(h ) h p (r ) r p (r )...P a ir -D is ta n c e D is tr ib u tio n F u n c tio n w ith in th e P a r tic le