X-ray Dif f ract ion • Basic aspects of x- ray crystallography and powder dif f raction • Dif f raction f rom nanocrystalline materials Paolo. Scardi@unitn. it Special thanks to: Luca Gelisio, Alberto Leonardi, Luca Rebuf f i, Cristy L. Azanza Ricardo, Mirco D’I ncau, Andrea Troian, Emmanuel Garnier, Mahmoud Abdellatief
PRESENTATI ON OUTLI NE PART I Dif f ract ion f rom nanocryst alline mat erials: why using synchrot ron radiat ion? PART I I Reciprocal space vs direct space met hods PART I I I Select ed case st udies: highly def ormed met als, and nanocryst alline cat alyst PART I V Tot al Scat t ering met hods Chapter XVI I I Dif f raction f rom nanocrystalline materials Paolo Scardi and Luca Gelisio 2 I CTP School - Trieste, 04. 04. 2016 P. Scardi – Dif f raction f rom nanocrystalline materials
SYNCHROTRON RADI ATI ON X-RAY DI FFRACTI ON main applicat ions of (powder / polycryst alline mat erial) dif f ract ion • Cryst al st ruct ure det erminat ion: st ruct ure solut ion and ref inement . • Line Prof ile Analysis (LPA): cryst alline domain size/ shape, lat t ice def ect analysis – nanocryst alline mat erials • Phase I dent if icat ion (Search-Mat ch procedures): pure cryst alline phases or mixt ures • Quant it at ive Phase Analysis (QPA): cryst alline and amorphous phases • Text ure Analysis (TA): det erminat ion of pref erred orient at ions • X-ray Residual St ress Analysis (XRSA): measurement of st rain f ield / elast ic behaviour 3 I CTP School - Trieste, 04. 04. 2016 P. Scardi – Dif f raction f rom nanocrystalline materials
DI FFRACTI ON PATTERN FROM A POLYCRYSTALLI NE 6000 Intensity 4000 2000 0 20 30 40 50 60 2 θ (degrees) powder (bulk polycryst alline) {220} 220 {120} 120 {020} 020 {110} 110 {100} 100 s 2 θ s y [Å -1 ] s s=Q/2 π =2sin θ / λ s x [Å -1 ] 4 I CTP School - Trieste, 04. 04. 2016 P. Scardi – Dif f raction f rom nanocrystalline materials
SYNCHROTRON RADI ATI ON X-RAY DI FFRACTI ON f rom single-cryst al t o powder dif f ract ion 5 I CTP School - Trieste, 04. 04. 2016 P. Scardi – Dif f raction f rom nanocrystalline materials
SYNCHROTRON RADI ATI ON X-RAY DI FFRACTI ON Powder dif f ract ion ‘elect ive’ geomet ry: Debye-Scherrer (1918) POWDER 6 I CTP School - Trieste, 04. 04. 2016 P. Scardi – Dif f raction f rom nanocrystalline materials
SYNCHROTRON RADI ATI ON X-RAY DI FFRACTI ON parallel beam, Debye Sherrer geomet ry of MCX (ELETTRA) 7 I CTP School - Trieste, 04. 04. 2016 P. Scardi – Dif f raction f rom nanocrystalline materials
DI FFRACTI ON PATTERN FROM A POLYCRYSTALLI NE peaks f rom nanocryst als are broad: why using SR ??? nanocryst alline powder 6000 Intensity 4000 2000 0 10 nm 20 40 60 80 100 120 140 2 θ (degrees) powder (bulk polycryst alline) {220} 220 {120} 120 {020} 020 {110} 110 6000 Intensity {100} 100 4000 2000 0 20 40 60 80 100 120 140 2 θ (degrees) 8 I CTP School - Trieste, 04. 04. 2016 P. Scardi – Dif f raction f rom nanocrystalline materials
SYNCHROTRON RADI ATI ON X-RAY DI FFRACTI ON • high brillance: bet t er count ing st at ist ics / short er dat a collect ion t ime / f ast kinet ics, in sit u, in operando st udies 9-cryst al analyzer: 1.500s ! (x100 count s) Lab inst rument : ~80.000s count s · N° of peaks =1 =25. 000 t ime 3 counts) 1000 100 Intensity (counts) Intensity (x10 100 10 10 40 60 80 100 120 140 10 20 30 40 50 60 70 80 90 100 2 θ (degrees) 2 θ (degrees) CuK α λ =0.15406 nm ESRF I D31 (now I D22) λ =0.0632 nm iron powder (ball milled) 9 I CTP School - Trieste, 04. 04. 2016 P. Scardi – Dif f raction f rom nanocrystalline materials
SYNCHROTRON RADI ATI ON X-RAY DI FFRACTI ON • high brillance: bet t er count ing st at ist ics / short er dat a collect ion t ime / f ast kinet ics, in sit u, in operando st udies Myt hen det ect or: 100 s !! (x100 count s) Lab inst rument : ~80.000s count s · N° of peaks =1 =350. 000 t ime 1000 Intensity (x10 3 counts) Intensity (counts) 100 100 10 10 10 20 30 40 50 60 70 80 90 100 110 40 60 80 100 120 140 2 θ (degrees) 2 θ (degrees) CuK α λ =0.15406 nm PSI MS-X04SA λ =0.072929 nm iron powder (ball milled) 10 I CTP School - Trieste, 04. 04. 2016 P. Scardi – Dif f raction f rom nanocrystalline materials
SYNCHROTRON RADI ATI ON X-RAY DI FFRACTI ON • narrow inst rument al prof ile: cont rol of inst rument al prof ile; high resolut ion and accuracy in measuring peak posit ion, int ensit y and prof ile widt h/ shape 0. 05° 0. 05° -0.2 -0.1 0.0 0.1 0.2 -0.2 -0.1 0.0 0.1 0.2 degrees degrees Lab inst rument : I D31 @ESRF: FWHM ≈ 0.05-0.1° FWHM ≈ 0.003-0.004° 11 I CTP School - Trieste, 04. 04. 2016 P. Scardi – Dif f raction f rom nanocrystalline materials
SYNCHROTRON RADI ATI ON X-RAY DI FFRACTI ON • ext ending t he accessible region of reciprocal space well beyond what t radit ional lab inst rument s can make λ 1 λ 2 <λ 1 12 I CTP School - Trieste, 04. 04. 2016 P. Scardi – Dif f raction f rom nanocrystalline materials
SYNCHROTRON RADI ATI ON X-RAY DI FFRACTI ON • ext ending t he accessible region of reciprocal space well beyond what t radit ional lab inst rument s can make 9-cryst al analyzer: 1.500s ! (x100 count s) Lab inst rument : ~80.000s : 6 peaks : 28 peaks (330), (411) (431), (510) (433), (530) (600), (442) (532), (611) (110) (200) (211) (220) (310) (222) (321) (400) (420) (332) (422) (521) (440) (620) (541) (622) (631) (444) (211) (310) (110) (200) (220) (222) 3 counts) 1000 100 Intensity (counts) Intensity (x10 100 10 10 40 60 80 100 120 140 10 20 30 40 50 60 70 80 90 100 2 θ (degrees) 2 θ (degrees) CuK α λ =0.15406 nm ESRF I D31 λ =0.0632 nm 13 I CTP School - Trieste, 04. 04. 2016 P. Scardi – Dif f raction f rom nanocrystalline materials
SYNCHROTRON RADI ATI ON X-RAY DI FFRACTI ON • ext ending t he accessible region of reciprocal space well beyond what t radit ional lab inst rument s can make: PDF analysis High-pr essur e pair dist r ibut ion f unct ion (PDF) measur ement of nano Pt (50 nm) at 12.5 GPa in Met hanol:Et hanol = 4:1. Focused X-r ay beam, 66. 054 keV , Br ookhaven Nat ional Labor at ory. Hong et al., Nat . Sci. Repor t s 6, 21434 (2016) 14 I CTP School - Trieste, 04. 04. 2016 P. Scardi – Dif f raction f rom nanocrystalline materials
SYNCHROTRON RADI ATI ON X-RAY DI FFRACTI ON • ext ending t he accessible region of reciprocal space well beyond what t radit ional lab inst rument s can make: PDF analysis High-pr essur e pair dist r ibut ion f unct ion (PDF) measur ement of nano Pt (50 nm) at 12.5 GPa in Met hanol:Et hanol = 4:1. Focused X-r ay beam, 66. 054 keV , Br ookhaven Nat ional Labor at ory. Hong et al., Nat . Sci. Repor t s 6, 21434 (2016) 15 I CTP School - Trieste, 04. 04. 2016 P. Scardi – Dif f raction f rom nanocrystalline materials
SYNCHROTRON RADI ATI ON X-RAY DI FFRACTI ON • t uning energy according t o adsorpt ion edges f or, e.g.: resonant scat t ering, in dept h measurement s (propert y gradient s) 600 Absorption edge of Fe 400 µ/ρ (cm 2 /g) µ ρ − t ρ = I I e 0 200 CuK α 0 4 6 8 10 12 14 16 18 20 X-ray energy (keV) 16 I CTP School - Trieste, 04. 04. 2016 P. Scardi – Dif f raction f rom nanocrystalline materials
SYNCHROTRON RADI ATI ON X-RAY DI FFRACTI ON • t uning energy according t o adsorpt ion edges f or, e.g.: resonant scat t ering, in dept h measurement s (propert y gradient s); cont rol f luorescence emission and absorption MCX beamline (Elet t ra), 15 keV Negligible absorpt ion: µ =2.71 cm -1 � µ R ≈ 0.07 5 10 Intensity (counts) 5 10 4 10 4 10 3 10 kapton 10 20 30 40 50 60 70 80 2 θ (degrees) Special t hanks t o: M. Abdellat ief I CTP School - Trieste, 04. 04. 2016 P. Scardi – Dif f raction f rom nanocrystalline materials
SYNCHROTRON RADI ATI ON X-RAY DI FFRACTI ON • increase energy � ext end Ewald sphere! high Q(=4 π sin θ / λ ) f or PDF analysis • increase energy � • st at ist ics / short t ime / kinet ics / in sit u / in operando • cont rol absorpt ion and inst rument al ef f ect s Powder diffraction data from a ball milled Fe1.5%Mo powder collected 1000 (a) on a traditional laboratory instrument (Rigaku PMG-VH, Bragg- Intensity (counts) Brentano geometry) with CuK α radiation ( λ =0.1540598 nm) and SR (Debye-Scherrer geometry): (b) ID31 (now ID22) at ESRF, Grenoble (F) ( λ =0.0632 nm), and (c) MS-X04SA at PSI, Villigen (CH) ( λ =0.072929 100 nm). On the right: schematic of reciprocal space with extension of the limiting sphere (radius 2/ λ ). 10 P. Scardi & L. Gelisio, “Diffraction from nanocrystalline materials”, in 30 40 50 60 70 80 90 100 110 120 130 140 150 Synshrotron radiation, ed. S. Mobilio et al., Springer 2015. Chap. XVIII,. 2 θ (degrees) Intensity (counts x 100) 1000 100 10 10 20 30 40 50 60 70 80 90 100 2 θ (degrees) Intensity (counts x 100) 1000 Powder diffraction and synchrotron radiation: 100 visit the MCX beamline at ELETTRA (J.R. Plaisier) 10 20 30 40 50 60 70 80 90 100 110 2 θ (degrees) 18 I CTP School - Trieste, 04. 04. 2016 P. Scardi – Dif f raction f rom nanocrystalline materials
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