歯논문제출.PDF

Size: px

Start display at page:

Download "歯논문제출.PDF"

세례 사공
5 years ago
Views:

1 Ion - implanted poly aniline

2 Polyaniline Drude model Variable range hopping (VRH ) model XPS (X- ray photoelectron spectroscopy ) X- ray diffraction (T hermoelectric power) implantation XPS XPS

3 W - plot X XPS Bibliography

4 Abstract Polyaniline camphor sulfonic acid (CSA ) m - cresol, free standing film polyaniline. Ar + implantation,. X, X- ray photoelectron spectroscopy (XPS ) peak. implantation. implantation,., (10 18 ions/ cm 2 ) implantation. X implantation, XPS peak heteroatom implantation.

5 Abstract T he r esult s of temperatur e dependence of DC conductivity and therm oelectric pow er (T EP ), X- ray diffr action, and X- ray photoelectr on spectroscopy (XPS) experiment s ar e r eported for Ar ion - implanted polyaniline samples doped with camphor sulfonic acid (CSA) in m - cr esol solvent [PAN - CSA (m - cresol)]. T he charge tr an sport pr operties are varied w ith the dosage lev el of ion - implantation. T he DC conductivity increases as the dosage lev el of ion implantation increases. T he metallic property of Ar ion - implanted (10 18 ions/ cm 2 dosage) sample is confirmed by temper atur e dependence of therm oelectric pow er experiment s. From XPS experiment s, w e ob serve that heter oatom such as oxy gen is r educed by the ion- implantation. T he X- ray diffraction pattern s of pristine and ion - implanted samples ar e presented.

6 doping dopant,,. pristine sp 2 pz, pz [1]. polyacetylene, polyaniline, polypyrrole., doping (soliton ), (polaron ), (bipolaron ) 1 (mobile defect ) [1].. polyaniline, 1 diffusion hopping variable range hopping [2][3]. implantation, doping [3]. implantation dosage, implantation. implantation,, X- ray photoelectron spectroscopy (XPS), X. implantation. XPS heteroatom, X implantation.

7 Chapter sp 2 pz [1]. pz. polyacetylene 2.1(a ) trans cis. valence, sp 2, 2.1(b) sp 2 pz [1]. sy stem model SSH model [2]. SSH model, coulomb, tight - binding LCAO ( ). SSH hamiltonian [2]. H S SH = K ( u 2 n u n ) 2 + M n 2 n ( du n dt ) 2 - t n + 1, n ( C + n + 1, s C n, s + C + n, s C n + 1, s ) n, s (2.1) un n. C- H,.. C +, C,, t transfer (hopping ) integral. t t n + 1, n t o - ( u n u n ) (2.2)

8 transfer integral. un 0, SSH Hamiltonian H S SH = k. s ( k) C + k, s C k, s ( 2.3) [8]. (k)=- 2t 0cos (ka), C k, s = ( 1/ N ) N n = 1 e - ikan C n, s (2.4). N, a, k wave- vector. Hamiltonian, valence band conduction band (band gap ),., 1 Peierls, dimerized,, Hamiltonian [8]., u n = ( - 1) n u (2.5) H S SH = 2NK u 2 + k, s E ( k)( a + ( c) k, s a ( c) k, s - a + ( v) k, s a ( v) k, s) (2.6) E ( k) = ( k) 2 + ( k) 2 ( 2, 7) ( k) = 4 usin ( ka) (2.8) a + ( c( v) ) k, s, a ( c( v) ) k, s conduction (c) valence (v ) band w ave- vector k spin s number operator. E (k), N ( E ) = (N / )( E / (4 t E 2 )( E 2-2 0) 0 E 2 t 0 (2.9) [8]. (E g ). E g = 2 0 = 8 u ( 2. 10) doping polyacetylene [2]. E 0 E 0 = 2K u 2-4 t 0 / E ( 1 - z 2 ) a + b u 2 - c u 2 ln (u) ( 2. 11), E (1- z 2 ) complete elliptic integral, z 2 u/ t 0 [8]. polyaniline, doping polyacetylene 2.2(a) gap sub- band. soliton band. soliton. (polyaniline, polypyrrole) 2.2(b )(c) polaron band bipolaron band Polyaniline

9 amine nitrogen (- NH - ) leucoemeraldine base (LEB) emeraldine base (EB), imine nitrogen (- N=) pernigraniline base [ 2.3]. polyaniline emeraldine base (PAN - EB) [ 2.3(b )] benzenoid, quinoid,,., doping. PAN - EB doping 1 (S/ cm ) emeraldine salt (ES ) polyaniline (PAN- ES ) [ 2.4]. polyaniline doping gap polaron band [ 2.2(b )], polaron [ 2.2]. Polyaniline sp 2 pz,. polyaniline.. amine nitrogen (- NH - ) site, pz. imine nitrogen (- N=),, pz.,, polyaniline, [7]. polyaniline conjugation path. polyaniline A - B Drude model. (I), (V), (R) [9]. I =. V R ( 2. 12) R = l A (2. 13), l, A.

10 [9], = n e 2 m ( 2. 14). n, e,, m., Variable r ange hopping (VRH ) model. mechanism [3]. E (2.15). = m in ex p ( - k T ) (2. 15) = E - E F, Boltzmann. Fermi hopping. hopping [12]. Fermi hopping. Boltzmann hopping. phonon. Phonon hopping., hopping. Fermi (disordered) E, hopping, hopping R, hopping. Fermi k T 2N (E F )k T, hopping P = ph ex p [ - 2 R - W er E k T ] (2. 16) [3]. E J [3]. J = 2eR k TN ( E F ) ph ex p ( - 2 R - W/ k T ) sinh (er E / k T ) (2. 17)

11 J = 2 e 2 R 2 E N ( E F ) ph ex p ( - 2 R - W/ k T ) (2. 18) J = E, (2.19). = 2 e 2 R 2 N ( E F ) ph ex p ( - 2 R - W/ k T ) ( 2. 19) hopping W (hopping energy ) (band width ). W 1/ R 3 0N ( E F ) ( 2.20) W, W = 3 4 R 3 N ( E F ) ( 2.21) [3]. hopping R m R m = R r 3 d r rd r = 3R 4 ( 2.22). hopping P P = ph ex p ( - 2 R m - W k T ) (2.23). R = 3 2 R 4 N ( E F )k T (2.24), R = 3 1/4 ( 2 N ( E F )k T ) 1/4 (2.25). hopping, P = ph ex p ( - T o / T 1/4 ) (2.26) T o = 6 3 kn ( E F ) (2.27) dc ( T ) = oex p [( - T o / T ) 1/ 4 ] ( 2.28), o = 2e 2 R 2 N ( E F ) ph ( 2.29). 3 hopping., ( T ) = ex p [ - ( T / T ) 1/ d + 1 ] ( 2.30)

12 variable range hopping (VRH ) model [3]. T o, disorder,. T 0, T 0. Fermi (N (E F )),. L, (localization length ). Fermi XPS (X- ray photoelectron spectroscopy ) XPS 1950, XPS X.. A + h A + + e - (2.31) A, h X, A +, e -.. E k X h core E b. E k = h - E b - (2.32), E k E b.,. 2.4 X- ray diffraction X-, Bragg. n = 2dsin ( 2.33) d. t.,,

13 . B B = 1 2 ( ) = 1-2 (2.34), (m +1), (m - 1), 2tsin 1 = ( m + 1) ( 2.35) 2tsin 2 = ( m - 1) ( 2.36), t( s in 1 - s in 2 ) = ( 2.37) 2 tcos( ) s in ( ) = ( 2.38), 1 2 B B ( 2.39) s in ( ) ( ) (2.40) 2 t( ) cos B = (2.4 1), t = 0.9 B cos B ( 2.42) B. Scherrer [14]., (coherence length). 2.5 ( T hermoelectric power).. Band theory p- type, n - type doping.. S ( T ) = <E - E F > / ( e T ) (2.43) e, <E - E F > Fermi [17]. <E - E F >. Fermi. Fermi

14 conduction band ( E C ). S E c / e T (2.44). electron - doped E C, hole- doped E C. Fermi. Fermi T [17].. (2.45) (2.51) [3][8]. S ( T ) = 2 2 k 2 B T 3e d lnn ( E F ) de = A 1 T (2.45) N, T. [3]. S ( T ) = k B W 2 2ek B T ( d lnn de ) W 2 E = E F T ( 2.46) W hopping [3][18]. 3D VRH W k B (T ot 3 ) 1/ 4 W 2 / k T = k ( T 0 T ) 1/ 2 ( 2.47) S ( T ) = A 2 T ( 2.48) Quasi- 1D VRH hopping hopping. hopping W T 1/ 2 S ( T ) = A 3 (2.49) hopping W kb T 0 S ( T ) = A 4 / T (2.50), S ( T ) = A 1 T + A 2 T + A 3 + A 4 / T ( 2.51) [3][8][18]. 2.6 Ion implantation

15 [4]. implantation. implantation.,,. heteroatom sp 2, sp 3.. Heteroatom [11]. sp 2... implantation,.

16 Chapter Polyaniline emeraldine base (PAN - EB) aniline monomer ammonium peroxydisulfate ((NH 4 )2S 2O8). Dopant PAN - EB mortar. dopant camphor sulfonic acid (CSA ). quinoid EB : acid = 1 : 2. m - cresol 2.5 (weight %). magnetic stirrer 30.. PAN - CSA (m - cresol). Ion implantation source argon (Ar ) PAN - CSA (m - cresol) implantation. (dosage) implantation.,. 1keV, 80 kev, 10 15, 10 16, (ions/ cm 2 ) argon ion implantation. 3.2 DC Conductivity sample contact R1, R2, R3, R probe 4- point. Film 4- probe. [9].

17 = 1 = 1 R l A (3. 1) (resistivity ), R, A, l (c). Cryogenics Model 22 refrigerator Cryogenics 8200 compressor He gas. 4- probe refrigerator cold finger. refrigerator LakeShore cry - con thermal conductive grease. gold wire refrigerator pin., refrigerator, mmt orr. Keithley high voltage source measure unit model 237 (SMU) 4 refrigerator. refrigerator LakeShore model DRC- 91CA (W att ).,. 1K 10K. GPIB bus IEEE interface. 3.3 XPS (X- ray photoelectron spectroscopy ) XPS XPS, 3.2.,,,,.,

18 . X : X peak.,, Si, Zr, Mg, Al, Ag, T i, Mg Al, Al Mg anode X. :. retarding grid magnetic type, electrostatic type., 3.3(a) Concentric Hemispherical Analyzer (CHA ). 3.3(b ) pass energy, : wide scan ( ev ).. Spectrum photoelectron peak, X- ray ghosts, satellite lines Auger lines., source anode [6]. :., ev (chemical shift )..,,. (E B ). ( E B ) i = k i q i + V ij + ( E r ) i + L ( 3.2) k i, qi, V ij, (E r) i, L. 5.8 ev (shift ).,.

19 : [6]. XPS,,. 3.4 (T hermoelectric power) Chaiken Kw ak [7] mm, 10 mm. 2 mm oxygen - free copper block carbon paste, gold wire DC conductivity. oxygen - free copper block GE varnish copper block. Copper block, block. manganin (83% copper, 13% manganese, 4% nickel), 10. Copper block SMU. Cu - constantan thermocouple copper block. Cryogenics Model 22 refrigerator. 50 mmt orr, [8]. T hermocouple Keithley 182 nanovoltmeter s (input impedance > 1G ). PC interface, DRC- 91CA. thermocouple 1 (3.3), (3.4). Copper block 10-2 (A ). copper block 1 o C. 10. [8]. fluctuation, [13]. chamber, stability., slope = V samp le coup le = S sam p le - S g old (3.3) S con st. - S coppe r Sg o ld, S c o n s t., S c o p p e r, constantan, [15]

20 S samp le = S g old + V samp le coup le ( S const. - S copper ) (3.4), [8] V. [13].

21 Chapter (DC conductivity ) Ion dosage PAN - CSA (m - cresol) dosage Ar ion implantation. Dosage 120 S/ cm ( pristine 50 S/ cm ), 80 kev implantation 10-3 S/ cm. 4.1 implantation. Dosage,. implantation 1 kev (4.1) power - law [8]. dc ( T ) = 0 T (4. 1) - critical property [12]. Pristine = 0.41, implantation 0.23, implantation pristine critical property, implantation implantation sp 2 conjugation path, dosage [11]. 80 kev 4.2 1D VRH. dc ( T ) = 0 ex p [ - ( T 0 T ) 1/ 2 ] (4.2) hopping [3][8]. insulating

22 . Pow er - law K S/ cm, 1D VRH S/ cm W - plot reduced activation energy (4.3). W. W( T ) = log 10 ( d ln d ln T ) (4.3) 4.3 ion implantation dosage. 4.2 X 4.4, X implantation pristine. implantation pristine,.. implantation sp 2 [11]. 4.3 XPS (X- ray photoelectron spectroscopy ) 4.5 XPS wide scan. 4.6 heteroatom [11] ions/ cm 2 implantation ions/ cm 2 implantation 3 4% % pristine ions/ cm 2 implantation 20 %, ions/ cm 2 implantation 23 %. implantation. impurity scattering center, [11]. implantation impurity

23 ... implantation. implantation conjugation path channelling [4]. 4.4 (thermoelectric power) [8][17] ions/ cm 2 dosage implantation p- type conduction. 4 V/ K. [8]. P- type conduction polyaniline polaron.. implantation.. w - plot.

24 Chapter 5 polyaniline ( d c (R. T ) 1 S/ cm ),. implantation. implantation. implantation PAN - CSA (m - cresol). pristine PAN - CSA (m - cresol).. reduced activation energy (W ), W.,. implantation. X implantation pristine. sp 2 pz, sp 3 PAN - CSA (m - cresol). XPS implantation pristine heteroatom. Impurity scattering center., implantation PAN - CSA (m - cresol).,. *.

KAERI/AR-636/2002 : 技術現況分析報告書 : 방사선 계측기술 및 중성자 계측기 기술 개발 현황

KAERI/AR-636/2002 : 技術現況分析報告書 : 방사선 계측기술 및 중성자 계측기 기술 개발 현황 KAERI Radiation Gas ions - electrons + Gas-filled Detector Power Supply V Voltmeter Log(Pulse Height) Ionisation Chamber Proportional Counter Geiger-Müller Counter High initial Ionisation Low

歯논문제출.PDF

歯논문제출.PDF