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恨向晏
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1 II XPS X Koopman XPS (GENERAL FEATURES) XPS XPS : XPS (UHV) X XPS XPS(iXPS)

2 (Electron Spectroscopy) 2 2

3 X XPS(X-ray Photoelectron Spectroscopy) ESCA(Electron Spectroscopy for Chemical Analysis) X XPS XPS XPS 1. X XPS(ESCA) (1) (2) (3) XPS (Hertz) ĤΨ i =E i Ψ i hν n Ψ i (n) E i (n) Ψ f (n-1,k) E f E K k (hν > E B ) i i hν f f f f E ( n) Ψ ( n) E ( n 1, k) Ψ ( n 1, k) + E ( e ) Φ (1) χ (1) tot tot tot tot K 2 3

4 (Electron Spectroscopy) : A + hν A +* + e E i (n) + hν= E f (n-1,k) + E K f i EK = hν Etot( n 1, k) Etot( n) E K = hν E B f i ( E = E n 1, k) E ( n) B tot tot 3. (1) (Primary process) A + hν A +* + e ( ) E k = hν E B A hν hν= E σ σ nl n l 4 σ ( ε) = παa 2 ( 2 l+ 1 ) 1( ε ε ) lr 2 ε ( l ) R nl, nl, l ε, l + 1 ε n,l (n l) ε R ε,l±1 n l σ n,l l n σ n,l σ σ Z σ 2 4

5 X (2) (secondary process) (A +* ) ( ) (i) ( ) A +* A + +hν ( ) (ii) ( ) A +* A ++* + e ( Auger) γ e - γ e a x 2 5

6 (Electron Spectroscopy) (E B ) (n,l,m,s) (Z) XPS XPS n n-1 ( ) E B = E f (n-1) E i (n) E B = Hartree- Fock (HF-SCF) SCF 1 2 Z M 0 E = i i + i i + ( 2J K ) = ε + ( 2J K ) i 1. Koopman 2 r ij ij i M ij ij M j j Koopman ( (Sudden Approximation)) N-1 n n ( 2 ij ij ) i E = ε 0 + J K i i= 1 i, j= 1 n n n ε i ( 2 ij ij ) ( 2 ik ik ) f 0 0 E = ε + + J K J K K i= 1 i, j= 1 i= 1 f i 0 EB E E ε K ( 2 JiK KiK) = = = ε n i= 1 Koopmans E B ev E B δe relax ad KT SCF EB ( K) = EB ( K) δerelax = EB δ Erelax : K 2 6

7 X V SCF E = E δe + δe + δ E B relax relat corr 2. E B = E f (n-1) E i (n) E B E B E B E B E B E B = - ε k E B E B Al 0 ( ) 2p 72.7eV Al 2 O 3 Al +3 2p 74.7eV 2eV -2(Na 2 S) +6(Na 2 SO 4 ) S 1s E B 8 ev ( Cu Ag ) XPS XPS C1s. 2 7

8 (Electron Spectroscopy) C 1s C C < C O <C=O < O C=O < O (C=O) O C1s E B E B (1). (Atom Potential Model) E B = V n + V v E B V n V v (2). (Charge Potential Model) Siegbahn Fadly 2 8

9 X A A E = E + E B V E A V M A ; E A M M A 0 q j EB = EB + kqi + j i r ij k q i M i q j i r ij i E B V i =Σq j /r ij Madelung q j 1 2 : E B = k [q i (2) q i (1)] + V i (2) V i (1) E B = k q i + V i q i i ( ) V i V i M i i ( ) V i q j Pauling V i =Σq j /r ij q i = Q i + ΣnI Q i i (formal charge) i i Q i >0; i Q i <0; Q i =0 n i n=1 n=2 n=3 I i ΣnI i I Χ Χ i j I 1 exp 1 ( ) 2 = Χi Χ j Χ Χ i j 4 Χ i,χ j Pauling ±1 X(+1)=X(Z)+ ⅔[X(Z+1) X(Z)] X( 1)=X(Z)+ ⅔[X(Z+1) X(Z)] a). E B b). E B ΣX (Group shift method) A M 2 9

10 (Electron Spectroscopy) 3. E B =E f (n-1) E i (n) (Shake up) (Shake off) XPS XPS (1). XPS (intra-atomicterm) (extra-atomicterm) int ra extra δerelax = δerelax + δerelax I K = I 0 + δe relax XPS ( ) ( ) ( ε K ) I = ε = I E i I, Koopmans I K ( () K K i B i i ( ) ) XPS (2). ( ) J XPS L S L' S' : L l L L+l, S =S±1/2, S 0 i 2 10

11 X L=L L=0,±1,±2,. S=S S=±1/2 l L'=l S'=1/2 XPS XPS L S (2S+1) S IS ( ) S + 1 = IS 1 S 2 ( ) (4f ) 4s 3d 3s s (3). X 20% (Shake up) (Shake off) ns n s np n p J = L = S = 0 XPS 2 11

12 (Electron Spectroscopy) Cu/CuO/Cu 2 O Cu 2p 3/2 2p 1/2 Cu Cu 2 O 2p 3/2 CuO 4. XPS " " " " V V E = hν E B K 2 12

13 X Fermi Fermi Fermi : V E = hν E Φ Φ hν B ( ) k sp s F V E = hν E Φ = hν E Φ B E k sp k V B = EB +Φ s s E VAC h ν V k Φ s e k Φ sp E E VAC F V B F B 5. 1 (~10-16 s) 2 hν<φ 3 E B +Φ>hν 4 5 (X-ray) 6 7 E B (1s) > E B (2s) > E B (2p) > E B (3s) 8 Z E B (Na 1s) < E B (Mg 1s) < E B (Al 1s) 9 E B ( 7 Li 1s) = E B ( 6 Li 1s). 2 13

14 (Electron Spectroscopy) XPS (General Features) XPS (I). (II). (III). XPS 1. XPS (1). (photoelectron lines) E F - E B Ti Ti 4+ Ti 2p 1/2 Ti 2p 1/2 Ti Ti 4+ 2p 2 14

15 X (2).. XPS (3). (Auger lines). ( ) XPS hν (4). - (SOS). - (s) (l) j = l±s j - = 2j

16 (Electron Spectroscopy) s - XPS p, d, f - XPS j E B (E B 2p1/2 > E B 2p3/2) - Z - ( ) (5). X- XPS 2 16

17 X 2. XPS i. X (X-ray satellites). XPS X X 2p 3/2 1s 2p 1/2 1s X Kα 1,2 ( ) Mg Al Kα 3,4 hν Kα 1, ev 3p 1s Kβ X X X ( ) X XPS ii. (shake-up lines). C 1s(π π * ) = ev iii. (multiplet splitting). s iv. (energy loss lines). ( ) ω b (ħω b ) 2 17

18 (Electron Spectroscopy) X 1nm 5nm XPS XPS 1. : XPS (1). (Survey scan) XPS eV C O p d f Mg Kα Al Kα (2). (Narrow scan or Detail scan) 2 18

19 X 2. XPS i. (Photoelectron line chemical shifts and separations). ( ) ( ev) C1s TiC(281.7eV) (284.3eV) CO 2 (297.5eV) XPS C H XPS NMR H He 2 19

20 (Electron Spectroscopy) ii. (Auger line chemical shifts and the Auger parameter). 100~3000eV X XPS AES C. D. Wagner 1972 XPS XPS α * E K (ijk) + E B (l) iii. (Shake-up lines) XPS C 1s iv. (Multiplet splitting) v. (Auger line shape) KVV LVV LMV XPS IR NMR 2 20

X 3 Case Study (1) (polymer) C O N S (i) C1s C (C C) H (C H) C1s 285eV ( O H C O C1s 1.5±0.2eV C O X X( X=NO 2 ) (±0.4eV) X=NO 2 0.9eV ( C ) ( C ) : Halogen Primary shift(ev) Secondary shift(ev) F 2.

21 X 3 Case Study (1) (polymer) C O N S (i) C1s C (C C) H (C H) C1s 285eV ( O H C O C1s 1.5±0.2eV C O X X( X=NO 2 ) (±0.4eV) X=NO 2 0.9eV ( C ) ( C ) : Halogen Primary shift(ev) Secondary shift(ev) F Cl Br 1.0 <0.2 1 C 1s Hydrocarbon, C H, C C Amine, C N Alcohol, ether C O H, C O C Cl bond to carbon C Cl F bond to carbon C F Carbonyl C=O Amide N C=O Acid, ester O C=O Urea Carbamate O N C N O O C N (ev) Carbonate O O C O 2F bond to carbon CH 2 CF Carbon in PTFE CF 2 CF

22 (Electron Spectroscopy) 3F bond to carbon CF * ±0.2eV ( ) (ii) O1s O1s 533eV 2eV (Carboxyl) (Carbonate group) 2 O 1s (ev) Carbonyl C=O, O C=O Alcohol, ether C O H, C O C ester C O C=O Water H 2 O * ±0.2eV (iii) N1s N1s eV CN NH 2 OCONH CONH 2 N1s ONO 2 ( 408eV) NO 2 ( 407eV) ONO( 405eV) (iv) S2p C1s ( 0.4eV) S2p R S R( 164eV) R SO2 R( 167.5eV) R SO3H( 169eV) (2) Fe Cr Ni Mo Si eV Cr 18 Ni 14.3 Mo C XPS Cr XPS Cr 2 O 3 Mo Cr 2 22

23 X Cr Cr 3 XPS XPS θ = 4 (ARUPS) E k E(k i ) E i = E f hν 1/2 2 m k = 2 ( Ei + hν ) sin θ h 2m k = E + h h 2 h 2 cos θ( i ν ν0) 1/2 InSb(001) hν = ~ ev hν 0 = 5.6 ev (a) (b) 2 23

24 (Electron Spectroscopy) 2 24

25 X 5 Trouble-shooting applications; Why has a particular material stopped working effectively? Correlation of surface composition with catalytic performance; Furthering the science of catalysis Interpretation of XPS data in terms of the size of supported crystallites XPS XPS Pd Pd 2 25

26 (Electron Spectroscopy) XPS XPS XPS 1. " " : z λ( E )cos ( ) ( γ) σ ( ) θ I = K T E L n z e dz ij ij ij i :I ij i j K T(E) L ij (γ) i j σ ij i j n i (z) i z λ(e) θ X γ X Lij( γ) = 1 βi ( 3cos γ 1) 4π 4 β i = β i (E k ) γ X θ=54.7 (magic angle) 3cos 2 γ 1=0 L ij (γ) L ij (γ) (First Principle Model) " " 2. ( ) : 2 26

27 X Iij = K T( E) Lij( ) ij ni ( E)cos = ( ) ( γ) σ λ( )cosθ = γ σ λ θ n I K T E L E I S i ij ij ij ij ij S ij =K T(E) L ij (γ) σ ij λ(e)cosθ T(E) L ij (γ) σ ij λ(e) S F1s =1 n i = I ij / S ij i j S i S j I i I j : ni Ii Si = n j I j Sj Ii Si : Ci = I j S j j 15% 5% 2% H He XPS XPS : ( ), d 1 ML S =S/λ 2 27

28 (Electron Spectroscopy) S S T T m n T Ea Ek VG ESCALAB MK : n = -0.5, m = 1.5 Hemminger : log I 2 E E = C 021. log a E : I I 1 2 Ea1 = 10 E a2 3 a 2 2 ( 2 1 ) E 021. log Ea log Ea 042. log Ek log E X k a 2 a1 4. B ϑ A A I B (1 ϑ A ) I 0 A B exp( ) 0 a ϑ A A I B λa cosθ 0 a I 1 exp A B = I B ϑa + ϑa ( λ cos ) A θ 0 IA = ϑ A IA 0 IA IB ϑa = 0 IB IA a A 1 ϑa 1 exp λa cosθ B d A B d 0 A IB = IBexp λa( EB) cosθ 2 28

29 X A 0 d A IA = IA 1 exp λa( EA) cosθ d A 1 exp 0 I A( A) cos A I λ E θ B = 0 IB IA d A exp λa( EB) cosθ d A λ A (E A ) λ A (E B ) 0 IA I B d A λacosθ ln IB I I [ ] C 1s O 1s 4 3 E k λ E 0.7 k Al Kα X C/O C 1s O 1s E B (ev) C 1s C 1s C 1s C 1s O 1s O 1s O 1s IC ( ) nc SC1s = = n IO ( ) O SO1s = 2 C:C:C:O:O = 3:1:1:1:1 C 5 H 10 O 2 CH 3 O CH 3 C O C H CH 3 CH 3 -CH 2 -CH 2 -CH 2 -O-CH=O 2 29

30 (Electron Spectroscopy) XPS X VG ESCALABMKII 1 (UHV) mbar (1) + (2) + + (3) + + (4) + ESCALAB MKII ( ) torr 2 X (1) X XPS X X 2 30

31 X Mg/Al X X MgKα hν=1253.6ev E=0.7eV AlKα hν=1486.6ev E=0.85eV X X 1-3 X (ev) FWHM(eV) (ev) FWHM(eV) Y M ζ Mg K α Zr M ζ Al K α Nb M ζ Si K α Mo M ζ Y L α Ti L α Zr L α Cr L α Ag L α Ni L α Ti K α Cu L α Cr K α Na K α Cu K α (FWHM) (2) (10eV 10keV) 0.2eV X

(Electron Spectroscopy) (CHA) (CMA) R 1 R 2 E 0 VR 1 1+ VR 2 2 V0 = 2R0 ev=v 0 R 0 R 0, R 1 R 2 V 1 V 2 (CAE) (CRR) E 0 E s = E0 2R0 s R 0 (FWHM)=0.1 1.0eV.

32 (Electron Spectroscopy) (CHA) (CMA) R 1 R 2 E 0 VR 1 1+ VR 2 2 V0 = 2R0 ev=v 0 R 0 R 0, R 1 R 2 V 1 V 2 (CAE) (CRR) E 0 E s = E0 2R0 s R 0 (FWHM)= eV. X FWHM total = ( FWHM 2 x-ray + FWHM 2 linewidth + FWHM 2 analyser) 1/2 0.7~1.0 ev <0.1 ev -1 CAE T E s CRR CRR CRR T E E s E s E XPS AES XPS XPS CAE AES AES CRR E s 2 32

33 X 1-4 CRR CAE CRR Mode CAE Mode E/E= 2 E= AES UPS 6 XPS A (channeltron) (MCD) (PSD) XPS 4 ( ) (Peak fitting) 5 XPS Ar + Doser 700 C -120 C 2 33

34 (Electron Spectroscopy) XPS (AES, ISS, SIMS, LEED, EELS ) Penning VG AG61 6 < 10 nm 0.1~1.0% H He : ~50µ( ), 5µ( ) 7 7 (±0.1 ev) Fermi Fermi Ni Pd E F B = 0 (ISO 15472: 2001) (ev) Al Kα Mg Kα Al Kα Au 4f7/ Ag 3d5/2 (368.22) (368.22) Cu L 3 VV Cu 2p3/ Ag 2 34

35 X 8 Si, Ge, GaAs, GaP Ar + ( ) 2 35

36 (Electron Spectroscopy) XPS 1 d>>λ Ar+ 2 (d ~ λ) (I). (II). (III). hν λ i E B θ λ i cosθ λ i (IV). Tougaard 1983 Tougaard E P A P 30 ev B D = A P /B 2 36

37 X ( ev) D XPS R 3 XPS(iXPS). XPS 2 37

38 (Electron Spectroscopy) 2 38

39 X XPS 1960 XPS XPS XPS H He XPS 10nm XPS >0.1% H, He <±10% 1 20 (<10 nm) ( ) π π* 10nm (1) XPS (2) 5~150μm X XPS XPS XPS XPS XPS 3. X 4. XPS 2 39

40 (Electron Spectroscopy) 2 40

41 X 2 41

42 (Electron Spectroscopy) 2 42

43 X 2 43

44 (Electron Spectroscopy) XPS Atomic Sensitivity Factors: Z Name Level ASF Level ASF Level ASF Level ASF Level ASF Level ASF Level ASF 1 H 2 He 3 Li 1s Be 1s Be 1s C 1s N 1s O 1s s F 1s 1 2s Ne 1s 1.5 2s Na 1s 2.3 2s Mg 1s 3.5 2s 0.2 2p Al 2s p Si 2s p P 2s p S 2s p Cl 2s p Ar 2s 0.4 2p K 2s p Ca 2s p Sc 2s 0.5 2p Ti 2s p 1.8 3p V 2p p Cr 2p 2.3 3p Mn 2p 2.6 3p Fe 2p 3 3p Co 2p 3.8 3p Ni 2p 4.5 3p Cu 2p 6.3 3p Zn 2p p Ga 3d p Ge 3d p As 3d p Se 3d p Br 3d p Kr 3d p Rb 3d p Sr 3d p Y 3d p Zr 3d 2.1 3p Nb 3d 2.4 3p

45 X 42 Mo 3d p Tc 3d p Ru 3d 3.6 3p Rh 3d 4.1 3p Pd 3d 4.6 3p Ag 3d 5.2 3p Cd 3p In 3p Sn 3p Sb 3d d 1 52 Te 3d d In 3d5 6 4d Xe 3d d Cs 3d d 2 56 Ba 3d d Hf 4f Ta 4f W 4f Re 4f Os 4f Ir 4f Pt 4f Au 4f Hg 4f Tl 4f Pb 4f Bi 4f 7.4 *Data from "Practical Surface Analysis. Volume 1. Auger and X-ray Photoelectron Spectroscopy" D, Briggs and M.P. Seah (Ed.) (John Wiley and Sons, Chichester, UK, 1990). Most intense peaks only. Valid for CHA-type analyzers. These values are semi-quantitative at best: ideally, a set of instrument-specific ASF's should be used or determined using well-known standard materials. 2 45

99710b45zw.PDF

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