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International Conference on Molecular Spectroscopy, Białka Tatrzańska 2017
104
T4: O–7
Annealing time effect on the optical properties of Zn(O,OH,S) films
onto ZnO seed layer under un-vacuum ambient
Fatma Özütok
1
,
and Emin Yakar
2
1
Physics Department, Çanakkale Onsekiz Mart University, Terzioğlu Campus, Turkey,
e-mail: fatmaozutok@comu.edu.tr
2
Materials Science and Engineering, Çanakkale Onsekiz Mart University, Terzioğlu Campus, Turkey
In the CIG(S,Se)solar cells, as a buffer layer Zn-based (ZnO, ZnSe, ZnS etc.) materials are
so attractive instead of toxic CdS [1]. In this study, Zn (O,OH,S) films were synthesized onto
ZnO seed layers by chemical bath deposition which annealed at 500 °C. ZnO seed layer
deposition given by our earlier study [2].The differences of structural, morphological and
detailed optical properties were investigated depending on the annealing time (between 30 min.
and 90 min.). While samples of 30.min and 90 min. showed decomposed structures, sample of
60 min. showed different sizes of nano-flower structures. Although all films have ZnO-
hexzagonal crystal structure, the most obvious ZnS-related peaks were observed in sample of 90
min. Optical absorption edge is shifted at 340 nm.and optical transmittance decreases by the
increase of annealing time as expected. The PL intensities can affected by the annealing time but
defect state-corresponding peaks are similar for each films.
Fig. 1. a) Photoluminescence spectrum of Zn(O,OH,S) films onto ZnO seed layers at room temperature
(λexc.=245 nm.) and b) Uv-Vis spectrum of Zn(O,OH,S) films onto ZnO seed layers, respectively.
Keywords: Zn(O,OH,S) film; ZnO seed layer; photoluminescence spectroscopy; FTIR; optical transperancy
Acknowledgment
This work was supported by the Council of Scientific Research Project (Grant number: FBA-2016-1051).
References
[1] K. Taizo, N. Tokio, Sol. Energ. Mat. Sol. C. 117 (2013) 526.
[2] Ö. Fatma, D. Sani, Dig. J. Nanomater. Bios. 12 (2017).
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International Conference on Molecular Spectroscopy, Białka Tatrzańska 2017
105
T4: O–8
Studies of substituent and solvent effect on spectroscopic properties
of 6-OH-4-CH
3
, 7-OH-4-CH
3
and 7-OH-4-CF
3
coumarin
Sanjay Kumar
1
1
Department of Physics, Rajdhani College, Delhi University, Raja Garden, New Delhi – 110015,
India, e-mail: sanjay_du1963@yahoo.co.in
This paper reports the solvent effects on the electronic absorption and fluorescence emission
spectra of 6-OH-4-CH
3
, 7-OH-4-CH
3
and 7-OH-4-CF
3
coumarin derivatives having –OH, –
CH
3
and –CF
3
substituent at different positions in various solvents (polar and non-polar). The
first excited singlet state dipole moment and ground state dipole moment were calculated using
Bakhshiev, Kawski – Chamma – Viallet and Reichardt – Dimroth equations and were compared
for all the coumarin studied. In all cases the dipole moments were found to be higher in the
excited singlet state then in the ground state indicating a substantial redistribution of π-electron
density in the excited state. The angle between the excited singlet state and ground state dipole
moment is also calculated. The red shift of the absorption and fluorescence emission bands,
observed for all the coumarin studied upon increasing the solvent polarity indicating that the
electronic transitions were π→π* nature.
Keywords: coumarin; solvent effects; absorption spectra; emission spectra; excited singlet state dipole moment;
ground state dipole moment; solvatochromism
XIV
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International Conference on Molecular Spectroscopy, Białka Tatrzańska 2017
106
T4: O–9
Stationary and time-resolved spectra analysis of pyrazoloquinoline
derivatives with pyridyl moiety
Anna Kolbus
1
, Danuta Grabka
1
, and Andrzej Danel
2
1
Institute of Chemistry, The Jan Kochanowski University, Swietokrzyska 15G, 25-406 Kielce, Poland,
e-mail: anna.kolbus@ujk.edu.pl
2
Institute of Chemistry, Faculty of Food Technology, University of Agriculture, Balicka St. 122, 31-
149 Kraków, Poland
In the last three decades there is observed considerable interest with organic materials. They
can be applied in electronics as organic diodes OLED, organic field-effect transistors OFET,
organic photovoltaic cells OPV or as fluorescent pigments. Fluorescent materials with nitrogen
heterocycles are promising compounds in this area of applications [1–3]. Among such
compounds are derivatives of pyrazoloquinoline with blue and green fluorescence [4–6]. These
compounds exhibit quite large quantum yield, especially in non-polar solvents [7, 8].
6-N,N-dimethyl-3-phenyl-1-(2-pyridyl)-1H-pyrazolo[3,4-b]quinoline (Fig. 1a) and 6-N,N-
dimethyl-1,3-(di-2-pyridyl)-1H-pyrazolo[3,4-b]quinoline (Fig. 1b) were synthesized. Stationary
adsorption and fluorescence as well as time-resolved fluorescence studies were performed.
Several electro-optical parameters were also calculated. Our results indicate CT fluorescence of
both compounds. Analyzed derivatives exhibit strong fluorescence and can be potential
candidates for electroluminescent applications.
Fig. 1. 6-N,N-dimethyl-3-phenyl-1-(2-pyridyl)-1H-pyrazolo[3,4-b]quinoline (a), and 6-N,N-dimethyl-1,3-
dipyridyl-1H-pyrazolo[3,4-b]quinoline (b). Colors black, grey and white represent C, N and H respectively.
Keywords: pyrazolo[3,4-b]quinoline; CT fluorescence; luminophores
References
[1] L. Mu, Z. He, J. Wang, G. Hui, Y. Wang, X. Jing, A. Danel, E. Kulig. IEEE Photonics Technology
Lett. 20(21) (2008) 1781.
[2] A. R. Tamaeev, Z. He, G.H.W. Milburn, A.A. Kozlov, A.V.Vannikov, A. Danel, P. Tomasik. Appl.
Phys. Lett. 77(3) (2000) 322.
[3] Y. Tao, T. Chen, P. Xu, H. Li, R. Chen, C. Zheng, L. Zhang, W. Huang, Adv. Mater. 26(47) (2014)
7931.
[4] K. Rechthaler, K. Rotkiewicz, A. Danel, P. Tomasik, K. Khatchatryan, G. Köhler. J. Fluoresc. 7(4)
(1997) 301.
[5] E. Koscień, E. Gondek, M. Pokładko, B. Jarosz, A.Danel, R.O.Vlokh, A.V.Kityk. Mater. Chem. Phys.
114 (2009) 860.
[6] E. Gondek, A. Danel, I.V. Kityk. Optoelectron. Adv. Mat. 2(1) (2008) 10.
[7] D. Grabka, A. Danel, . Kolbus, K. Szary, Opt. Mat. 66 (2017) 527.
[8] Z.He, A. Danel, G.H.W.Milburn. J. Luminesc. 605 (2007) 122.
a)
b)
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