Impedance Spectroscopy and Dielectric Relaxation in Phthalocyanine Thin Film

Öz

Dielectric relaxation behavior of spin coated thin film of novel ball-type binuclear zinc(II) phthalocyanine were studied using impedance spectroscopy technique over a frequency range of 5–13x10⁶ Hz and temperatures (298 – 468 K). Simulation of the obtained impedance data indicated that the dielectric behaviour of the system can be modeled by a parallel RC electrical equivalent circuit. A frequency dependence in the form of ω^m, where the index m is found strongly temperature dependent, was observed for the ac conductivity σ_ac. Ac conductivity data were analyzed in terms two different models. The observed temperature dependence of the m indicate that the ac charge transport in Pc film take place via hopping process.

 

Anahtar Kelimeler

• Phthalocyanine,Impedance,Relaxation,Ac conductivity,CBH model

FTALOSIYANIN İNCE FILMDE EMPEDANS SPEKTROSKOPI VE DIELEKTRIK DURULMA

Öz

Döndürerek kaplama yöntemiyle hazırlanan top tipi çinko (II) ftalosiyanin ince filmlerin dielektrik durulma davranışları 5 Hz. ile 13x10⁶ Hz frekans aralığında sıcaklığa bağlı olarak (298 K – 468 K sıcaklık aralığında) empedans spektroskopi yöntemiyle incelenmiştir. Elde edilen verilerin modellenmesinde sistemin dielektrik davranışının paralel RC eşdeğer devre ile temsil edilebileceği görülmüştür. Filmlerde ac iletkenliğin frekansa bağlılığının ω^m şeklinde olduğu ve frekansın üssü olan m parametresinin kuvvetle sıcaklığa bağlı olduğu gözlemlenmiştir. Deneysel olarak elde edilen ac iletkenlik verileri iki farklı model kullanılarak analiz edilmiştir. Frekansın üssü olan m parametresinin sıcaklığa bağlılığının incelenmesinde çinko (II) ftalosiyanin ince filmlerde ac yük iletiminin hoplama mekanizması sayesinde gerçekleştiği sonucuna varılmıştır.

Anahtar Kelimeler

• Ftalosiyanin,Empedans,Durulma,Ac iletkenlik,CBH model

Kaynakça

1. Altındal, A. Abdurrahmanoğlu, Ş. Bulut, M. Bekaroğlu, Ö. (2005) Charge transport mechanism in bis(double-decker lutetium(III) phthalocyanine) (Lu2Pc4) thin film. Synthetic Metals, 150, 181–187. doi: 10.1016/j.synthmet.2005.02.006
2. Altındal, A. Kurt, Ö. Şengül, A. Bekaroğlu, Ö. (2014) Kinetics of CO2 adsorption on ball-type dicopper phthalocyaninethin film. Sensors and Actuators B, 202, 373–381. doi: 10.1016/j.snb.2014.05.107
3. Anthopoulos, T.D. Shafai, T.S. (2003) Electrical properties of a-nickel phthalocyanine/aluminium interfaces: effects of oxygen doping and thermal annealing. Journal of Physics and Chemistry of Solids, 64, 1217–1223. doi: 10.1016/S0022-3697(03)00062-3
4. Bao, Z. Lovinger, A.J. Dodabalapur, A. (1996) Organic field‐effect transistors with high mobility based on copper phthalocyanine. Appl. Phys. Lett., 69(20), 3066-3068. doi: 10.1063/1.116841
5. Ceyhan, T. Altındal, A. Erbil, M.K. Bekaroğlu, Ö. (2006) Synthesis, characterization, conduction and gas sensing properties of novel multinuclear metallo phthalocyanines (Zn, Co) with alkylthio substituents. Polyhedron, 25, 737–746. doi: 10.1016/j.poly.2005.07.046
6. Ceyhan, T. Altındal, A. Özkaya, A.R. Çelikbıcak, Ö. Salih, B. Kemal Erbil, M. Bekaroğlu, Ö.( 2007) Synthesis, characterization and electrochemical properties of novel metal free and zinc(II) phthalocyanines of ball and clamshell types. Polyhedron, 26, 4239–4249. doi: 10.1016/j.poly.2007.05.028
7. Eliot, S.R. (1977) A theory of a.c. conduction in chalcogenide glasses. Philos. Mag., 36 (6), 1291-1304. doi: 10.1080/14786437708238517
8. Garcia-Belmonte, G. Boix, P.P. Bisquert, J. Sessolo, M. Bolink, H.J. (2010) Simultaneous determination of carrier lifetime and electron density- of-states in P3HT:PCBM organic solar cells under illumination by impedance spectroscopy. Solar Energy Materials & Solar Cells, 94, 366–375. doi: 10.1016/j.solmat.2009.10.015

9. Jonscher, A.K. (1983) Dielectric Relaxation in Solids. Chelsea Dielectric Press, London
10. Khrishnakumar, K.P. Menon, C.S. (2001) Determination of the thermal activation energy and grain size of iron phthalocyanine thin films. Materials Letters, 48(2001), 64–73. doi: 10.1016/S0167-577X(00)00281-0
11. Kimura, M. Horai, T. Hanabusa, K. Shirai, H. (1997) Electrochromic polymer derived from oxidized tetrakis(2-hydroxyphenoxy)phthalocyaninatocobalt(II) complex. Chem. Lett., 7, 653-654. doi: 10.1246/cl.1997.653
12. Kumar, A. Murari, N.M. Katiyar, R.S. (2009) Investigation of dielectric and electrical behavior in Pb(Fe0.66 W0.33)0.50Ti0.50O3 thin films by impedance spectroscopy.J. Alloys. Compd., 469, 433–440. doi: 10.1016/j.jallcom.2008.01.130
13. Leon, C. Lucıa, M.L. Santamarıa, J. (1997) Correlated ion hopping in single-crystal yttria-stabilized zirconia. Phys. Rev. B., 55, 882-887. doi: 10.1103/PhysRevB.55.882
14. MacDonald,J.R. (1987) Impedance Spectroscopy: Emphasizing Solid Materials and Systems, Wiley-Interscience, New York
15. Manaka, T. Iwamoto, M. (2003) Electrical properties of unsubstitutedyfluorine-substituted phthalocyanine interface investigated by Kelvin probe method. Thin Solid Films, 438–439, 157–161. doi: 10.1016/S0040-6090(03)00726-0
16. Pandey, R. Zou, Y. Holmes, R.J. (2012) Efficient, bulk heterojunction organic photovoltaic cells based on boron subphthalocyanine chloride-C70. Applied Physics Letters, 101, 033308-1-033308-4. doi: 10.1063/1.4737902
17. Piasecki, T. Nitsch, K. (2010) Study of sprayed coatings and compound materials by impedance spectroscopy. Surface & Coatings Technology, 205, 1009-1014. doi: 10.1016/j.surfcoat.2010.07.074
18. Shafai, T.S. Anthopoulos, T.D. (2001) Junction properties of nickel phthalocyanine thin film devices utilising indium injecting electrodes. Thin Solid Films, 398–399, 361–367. doi: 10.1016/S0040-6090(01)01345-1
19. Shan Do, J. Jen Chen, P. (2007) Amperometric sensor array for NOx, CO, O2 and SO2 detection. Sensors and Actuators B., 122, 165–173. doi: 10.1016/j.snb.2006.05.030
20. Vidadi, Y.A. Rozenshtein, L.D. Chistyakov, E.A. (1969) Hopping and band conductivities in organic semiconductors. Sov. Phys. Solid State, 11, 173-175.
21. Waclawek, W. Kulesza, M. Zabkowska, M. (1981) Mater. Sci. (Poland), 7, No:2-3, 385.