MANIFESTATION OF NANOINTERFACES IN TRANSPORT

PROPERTIES OF THE N-PHENYLENES

I.V. KITYK,

S.W.TKACZYK

Institute of Physics, Czestochowa UT , Poland

E-mail: iiwank74@gmail.com

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Main features of the films:

• N-phenylene films with different thickness deposited on a glass;

• Correlation between the film thickness and sizes of the MC.

• Interface sheet of the crystallites and their sizes

• Influence of the deposition conditins on the sizes of the NC

• Photoinduced operation by the film micro- and nanocrystalline (NC) sizes

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Transport measurements of the films using four probe method;Optically induced treatment of the micro-crystalline and nanocrystalline morphology;Creation of illumination regimes below and about destruction limit of materials to operate by structural, optical and electronic properties of materials.X-Ray, UV-visible and non-linear optical monitoring.

Basic methods of materials investigations:

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Goal of investigations:

Photoinduced operation parameters of the phenylene nanocrystallites.

Exploration of contribution of different microcrystallite sizes to the transport properties

Correlation between the macrostructural properties and nanosizes of the film crystallites

Creation of the optically operated nanocrystallites treated by different temperature.

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Photoinduced crystallization under treatment under power density about 0.2 GW/cm2 at 100 K

N=4. N=5.

N=6.

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Phototreatment of p-sexyphenyl/glass BK-7.

P-GLASS BK-7P-SEXIPHENYL/GLASS BK-7

GGLALASS BK-7GLASS KB-7

20m20 m

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Typical changes of organic films

(a) Morphology of films before illumination

(b) Morphology of films after illumination by coherent optical light with power density 0.76 GW/cm2.

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Photoinduced changes in N-phenyl.

Fig. 1. General geometry of electrodes and substrates.

The diameters of the glasses about 40 mm. The widths

of electrodes (upper gold and lower aluminium) – 2

mm; p-sexiphenyl surface 20 mm x 20 mm.

Fig. 2. Electronic photography of the p-

sexiphenyl/glass substrate.

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Dependence of the transport properties versus the photoinduced tratment at different temperatures, which correspond to different sheet sizes: 15 K – 1.6 nm; 305 K – 2.7 nm; 320 K – 3.1 nm.

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Typical current-voltage depndences for the samples optically-treated of different sizesof microcrystalites.

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Contribution of different parts of the microcrystalline into the transport properties of the N-phenylenes

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Principal schema of the interface, amorhpus-like and crystalline levels in the N-phenylenes

13Fig. 12. Grain boundary topology of the sexiphene

films.

Fig. 10. Layered-like structure of the sexiphene

crystallites.

Fig. 11. Non-planarity of the starting molecule.

MD/QC simulations of photoinduced changes during the illumination.

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Principal schemat of optical treatment of N-phenylene films

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-BBO F2

L2

M1

M2 M4

P2P1

L1

PM

FSSh

Sh

M3

Fund. laser

15

0d

1 m

P

0P

Fig. 1. General scheme of the medium polarization for the pure electronic contribution.

0

har

d

pump

P

0P

Fig. 2. Electronic + harmonic electron-phonon contribution.

Principal methods of creation of non-centrosymmetry.

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0

har

pump

d P 0

P

anhar

Fig. 3. Electronic + harmonic electron-phonon + anharmonic electron-phonon contribution .

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Specimens

YAG: Nd3+

N2- laser

PM

BS1

BS2

BC

P1

P2

M

DL

S

PM

MN

PM2

Photoinduced non-cohrent optical teatment of theN-phenylenes

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Fig. 5. The dependence lnI=f(kT-1) for for p-sexiphenyl films, Au-Al for different voltage electrode polarities: a) sample thickness d=2.0 m, polarities electrode Au(+).

Fig. 6. The dependence of I=f(U) (log plot) for: a) p-

sexiphenyl cohrently treted at temperature T=200 K;

Au-Al.; Al.(-).

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(Fig. 7.)

(Fig. 8.)

(Fig. 9.)

Fig. 7. Current-voltage characteristics for polycrystalline films

of the p-sexiphenyl layers. The dependence I=f(U) (log plot) for

temperature of optical treatment T=20 K; Au-Al, d=2 m using

different polarities of electrodes.

Fig. 8. Current-voltage characteristics for polycrystalline films

of the p-sexiphenyl layers. The dependence I=f(U) (log plot) for

temperature T=20 K; Au-Al, d=0,23 m using different

polarities of electrodes.Coherent poling.

Fig. 9. Current-voltage characteristics for polycrystalline films

of the p-sexiphenyl layers. The dependence I=f(U) (log plot) for

temperature T=20 K; Au-Al, d=2 m using different polarities

of electrodes.Incoherent poling.

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Before the optical coherent illumination NC sizes 2.1 nm

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Typical occurrence of the morphological structure in the N-phenylene films after low-temperature optical treatment

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Photoinduced second-order optical effects calculated for the bulk-like and nano-confined (dotted line) consideration.

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After phototreatment at T=20 K NC sizes 1.3 nm

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CONCLUSIONS:Possibility of operation by the sizes of the nanocrystallites within the microcrystallite matricesOperation by the transport propeprties through the changes of the photoinduced treatment regime and temperature of the treated crystallites.Dominant role of the nanosheets in the transport propertiesCrucial role of the photoinduced non-linear contribution in the observed effects.Creation of technology for manufacturing of nanocomposites possessing enhanced transport effects on the base of organic microcrystalline films.