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Published by Harish N, 2019-07-05 02:24:55

NCASMDT final file

NCASMDT final file

Advances in Semiconductor Materials and Device Technologies

3,450W Xenon source with excitation 403nm and cm-1 is assigned to combined vibrations of BO4
recorded in the region 500 -800nm. Gamma Chamber and PbO4 groups and Te-O bonds stretching
5000, Maximum 60Co source capacity 518 TBq vibrations in TeO3 units9,10. The second band:
(14000 Ci), dose rate at maximum capacity, ~9kGy/ 800-1200 cm-1 is due to B-O stretching vibrations
hr(0.9MRad/hr) at the centre of sample chamber.
After subjection of radiation of TS series for 3hr in BO4 units. The band at 890 cm-1 which is
32min (30kGy) the samples were again characterized characteristic of the stretching vibrations of B-O
using FTIR, Raman and PL to know the effects and
changes caused by irradiation. For the convenience bonds in BO4 tetrahedra from diborate groups11
samples are named after irradiation as TS0_G, and a band centred at 1005 cm-1 assigned to B-O
TS05_G, TS1_G and TS2_G for Sm3+ 0, 0.5, 1,2mol
% respectively. bonds stretching vibrations in BO4 tetrahedra
(oxygen atom bridging two boron atoms) from
3. Results and Discussion
tri-, tetra- and penta-borate groups. Further the
a) FTIR
band from 1200 cm-1 to 1600 cm-1 is due to
The FTIR spectrum shown in Fig 1(a) and (b)
consists of three bands in the wavenumber stretching vibration of BO3 units12. The band at
range: 500-800 cm-1, 800-1200 cm-1 and 1200- 1231 cm-1 is a characteristic of the B-O bonds
1600 cm-1 7. The first band in the wavenumber
range of 500-800 cm-1 is due to Te-O vibrations asymmetric stretching vibrations from pyro-
in different Te-O structural units8. The shoulder
at 618 cm-1 is assigned to O-B-O bonds bending and ortho-borate groups, the band centred at
vibrations and Te-O bonds stretching vibrations
in TeO4 units, while the band centred at 688 1388 cm-1 is a characteristic of the asymmetric

stretching mode of borate triangles (BO3) and
the small band centred at 1494 cm-1 assigned to

the stretching vibrations of borate triangles with

non bridging oxygen (NBO)13. Anyhow non-

irradiated and irradiated samples show not much

variation in vibration modes, slight broadening

is majorly have been observed.

Fig. 1(a) FTIR spectra of non irradiated samples (b) FTIR spectra of irradiated sample

b) Raman studies polyhedra and TeO3 units14. The second band
The Raman spectrum is shown in Fig 2 (a) comprises of two merged broad band centring
at 764 and 851cm-1 which can be attributed to
and (b) which consists of three bands in the Te-O bonds stretching vibrations in TeO3 tp
wavenumber range: 300-500 cm-1, 500-1000 units or TeO3+1 polyhedra , symmetric breathing
cm-1 and 1000-1800 cm-1. The first band centred vibrations of six member ring with one or two
at 302 cm-1 is due to the symmetric stretching BO4 tetrahedral and Te-O-B bonds vibrations15.
bending vibrations of Te–O–Te linkages which The third band also a combination of four
are formed by corner sharing of TeO4, TeO3+1

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Advances in Semiconductor Materials and Device Technologies

bands, band at 1182 cm-1 can be attributed to the bond breaking of TeO4 networks16.17. Lastly
bands at 1509 and 1625 cm-1 may be attributed
stretching modes of terminal oxygen’s (B-O-) to B–O stretching vibrations in BO3 units from
varied types of borate Groups18. The irradiated
belonging to metaborate triangles. Band at 1338 and non irradiated Raman spectra shows similar
cm-1 can be assigned to the overtone of the out- bands but with slight variation in intensity of
of-plane bending mode of BO33−. Initially, the bands which may be due to irradiation.

introduction of B2O3 breaks the TeO4 into TeO3
units, but at higher concentrations of B2O3, it
involves in forming the BO3 group rather than

Fig. 2(a). Raman spectra of non irradiated samples (b). Raman spectra of irradiated samples

c) Photoluminescence spectra TS2 proves to be better sample as even after
subjection of irradiation the emission property
Photoluminescence (PL) spectra of the Sm3+: is unaltered.

TS glasses recorded at room temperature in 4. Conclusion

the wavelength region 550–750 nm with an Radiation effects on tellurium oxide varied samarium
doped lanthanum- lead- borate glasses were
excitation of 403 nm is shown in Fig. 3. For the successfully carried out and discussed in detail. When
a glass is subjected to ionizing radiation such as
comparison both non irradiated and irradiated gamma radiation dose becomes darkly colored which
is due to the generation of radiation induced defects.
were subjected to PL analysis surprisingly for Majorly borate glasses related functional groups were
observed in FTIR, Raman structural studies. Whereas,
TS05 irradiated sample intensity is decreased PL spectra reveals that TS2 proves to be better sample
as even after subjection of irradiation the emission
where as for TS2 irradiated sample not affected property is unaltered this exhibits shielding property.

by any means. The spectra exhibits four

emission peaks at 563, 599, 646 and 712 nm

corresponding to 4G5/2→6H5/2, 6H7/2, H6 and
9/2

6H11/2 transitions, respectively19-21. Among the

four observed bands, the 4G5/2→6H7/2 transition
is more intense. The 4G5/2→6H7/2 and 4G5/2→6H9/2
transitions correspond to the orange and red

emission respectively. PL spectra reveals that

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Advances in Semiconductor Materials and Device Technologies

Fig. 3(a). Emission spectra of non irradiated and samples (b). Emission spectra of non irradiated and irradiated

irradiated samples

Acknowledgment 10. L. Griguta and I. Ardelean, Modern Physics Letters B,. 21,
No. 26 (2007) 1767.
The authors acknowledge DST purse project, Dept.
of Physics, Bangalore University, Bengaluru, for 11. Jlassi. I., Elhouichet. H., Ferid. M., Chtourou. R. &
extending Raman experimental facility. Oueslati. M. Opt. Mater. 32 (2010)743.

REFERENCES 12. Ruijie Cao, Yu Lu, Ying Tian, Feifei Huang, Yanyan Guo,
Shiqing Xu & Junjie Zhang, Sci. Rep. 6 (2016) 37873.
1. Bishay A, J.Non-Cryst solids, 3(1970) 54.
13. E. I. Kamitsos, M. A. Karakassides and G. D. Chryssikos,
2. Friebele E J ,Griscom D L, Treaties on materials science and J. Phys. Chem. 91 (1987)1073.
technology.Eds M. Tomozawa, R.H. Doremus (Academic
press. New York), 17(1979) 257. 14. G. Upender, V.G. Sathe, V. Chandea Mouli, Phys. Chem.
Glasses 50 (2009) 399.
3. Ezz-Eldin F M.Elalily N A, El-Batal H A, Ghoneim N,A,
J.Rad Phy Chem 48(1996) 811. 15. M. Arnaudov, V. Dimitrov, Y. Dimitrov, L. Markova, Mater.
Res. Bull. 17 (1982)1121.
4. Friebele E J in optical properties of glass (Eds) D R
Uhlman, N J Kreidl (American ceramic society, Ohio 16. E. I. Kamitsos and M. A. Karakassides, Phys. Chem.
USA) 1991, 205. Glasses, 30, (1989) 19.

5. A.F Abbas, F M Ezz- Eldin, Indian journal of pure and 17. K. Nakamoto, Infrared and Raman Spectra of Inorganic
applied physics, 38(2000) 714. and Coordination Compounds, Wiley, New York, (1978).

6. M.A. Marzouk, Journal of Molecular Structure 1019 18. C. Gautam, A.K. Yadav, V.K. Mishra, K. Vikram, J. Inorg.
(2012) 80. Non-metallic Mater. 2(2012) 47.

7. S. Rada, M. Culea, Journal of Non-Crystalline Solids 354, 19. M Jayasimhadri, Eun-Jin Cho, Ki-Wan Jang, Ho Sueb Lee
(2008)5491. and Sun II Kim, J. Phys. D: Appl. Phys. 41(2008)175101.

8. H. Burger, W. Vogel, V. Kozhukharov, M. Marinov, Journal 20. N. Sooraj Hussain, G. Hungerford, R. El-Mallawany, M. J.
of Material Science 19 (1984) 403. M. Gomes, M. A. Lopes, Nasar Ali, J.

9. T. Sekiya, N. Mochida, A. Ohtsuka, A. Soejima, Journal of D. Santos, S. Buddhudu, J. Nanoscience and Nanotechnology
Non-Crystalline Solids 15 (1992) 222. Vol.8 (2008)1.

21. R. Praveena,V.Venkatramu, P.Babu,C.K.Jayasankar,
Physica B, 403 (2008)352.

 43

OPTICAL STUDIES ON ZINC-BORO-VANADATE
GLASSES CONTAINING SULPHATE IONS

N. Sivasankara Reddy1,2, M. Sudhakara Reddy3, Asha Rajiv3, C. Narayana Reddy4* 1Department
of Physics, School of Engineering, Presidency University, Bengaluru - 560064, India 2Department of
Physics, CPGS, Jain (Deemed-to-be University), Bengaluru-560011, India 3Department of Physics, SGS,
Jain (Deemed-to-be University), Bengaluru-560027, India. 4 Department of Physics, PES Degree College,
Bengaluru-560050, India *Corresponding author: C Narayana Reddy, Email: [email protected]

Abstract coordinated environments and the strong covalent
B-O bonds enable borates to form stable glasses.
Glasses were synthesized by using the general The host borate glasses containing ZnO, PbO, BaO,
formula xZnSO4-10ZnO-(90-x)[0.50 B2O3-0.50 SrO as modifiers are optimistic materials for their
V2O5], where 5 ≤ x ≤ 25 mol% were synthesized using applications in the field of optical communications
microwave heating method. Optical absorption laser hosts, optical filters, photonic devices etc. [3-4].
studies were carried out on these glasses. The In the present study we attempted to study the optical
optical absorption spectra of all glasses reveal two properties of borate glasses containing transition
bands at about 505 nm (19,802 cm-1) and 602 nm metal ions in order to find the suitability of these
(16,611 cm-1) are characteristic of vanadyl VO2+ glasses for electro-optic applications.
ions in a tetragonal crystal field (C4V) of distorted
octahedral (Oh) sites and correspond to the 2. Experimental Procedure
transitions 2B2g→2A1g and 2B2g→2B1g respectively.
The values of optical band gap decrease from 2.77 Glasses were synthesized by using the general formula
to 2.26 eV for indirect allowed transitions when xZnSO4-10ZnO-(90-x)[0.50 B2O3-0.50 V2O5], where
ZnSO4 concentration increased from 5 to 25 mol%. 5 ≤ x ≤ 25 mol% by a microwave heating technique
The values of molar electronic polarizability are in using analar grade zinc sulphate (Sd fine chemicals),
the range 5.83-6.10 Å3. The metallization criterion zinc monoxide (Sd fine chemicals), boric acid (Sd
M decrease, the metallic character of the solid fine chemicals) and vanadium pentoxide (Merck) as
increases and insulating property decreases when chemical ingredients. The detail of the microwave
ZnSO4 concentration increased. synthesis is described elsewhere. The sample codes
were designated as ZBVS1, ZBVS2, ZBVS3, ZBVS4
Keywords: Optical band gap, Transition metal ion, ZBVS5 and for x = 5, 10, 15, 20 and 25 mol%
Optical absorption, Urbach energy respectively. The UV-Visible absorption spectra of
the synthesized glasses were recorded using a Perkin
1. Introduction Elmer (Lamda 35) spectrometer in the UV-Vis-NIR
region in the range of 200 to 1000 nm.
Glasses containing transition metal ions (TMI) such
as Fe2O3, V2O5, MoO3, WO3 etc. exhibit superior 3. Results and Discussion
semiconducting properties and find useful applications
in solid state batteries [1]. Borate is one of the most a) OPTICAL ABSORPTION STUDIES
widely used glass forming oxides due to its superior
chemical, physical properties and can form glass The optical absorption spectra of the investigated
over a wide range of compositions. The network of glasses were recorded at room temperature
borate glasses composed of BO3 triangles and BO4 is shown in Fig. 1. The non-sharp optical
tetrahedra, gathering of these units’ results in the absorption edge present in the absorption spectra
formation of well-defined stable borate groups such confirms the glassy nature of the samples. For
as diborate, triborate and tetraborate [2]. The unique all the glasses, only two intense absorption
property of boron to exist in three and four oxygen bands were observed. These bands were at about

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Advances in Semiconductor Materials and Device Technologies

505 nm (19,802 cm-1) and 602 nm (16,611 cm- transitions 2B2g→2A1g and 2B2g→2B1g, which
are usually observed in the region 23,000-26,700
1). These two bands are typical for VO2+ ions
cm-1 and 14,000-17,400 cm-1 respectively [5].
in a tetragonal crystal field (C4V) of distorted
octahedral (Oh) sites and correspond to the

Fig. 1. Optical absorption spectra of ZBVS glasses

b) OPTICAL BAND GAP (EOPT) AND that occur in the glass matrix due to the addition
URBACH ENERGY (∆E) of ZnSO4. The decrease in band gap energy
is also attributed to the increase in degree of
The method of estimation of optical band gap delocalization of electrons due to increasing
(Eopt) values are estimated from the Tauc plots concentration of larger SO42- ions occupying the
shown in Fig.2 corresponding to indirect allowed interstitial positions of the network structure of
Mott’s transition for all the glasses using the boro-vanadate glasses [7]. Moreover the addition
relation proposed by Mott and Davis [16]. The ZnSO4 leads to the oxygen anions loosely bound
Eopt values are presented in the Table.1. The to the host material [8], an increase in the
values of optical band gap decrease from 2.77 concentration of bonding defects. As a result the
to 2.26 eVfor indirect allowed transitions due to degree of delocalization of electrons increases
the increase of ZnSO4 concentration from 5 to which in turn increases the donor centers in the
25 mol% (see Fig. 3). The values are comparable glass network. The improvement in these donor
to the reported data Eopt = 2.5 - 2.7 eV for the centers decreases the optical band gap and
glasses B2O3-BaO-V2O5 [6].The variations in shifts the absorption edge towards the longer
Eopt can be attributed to the structural changes wavelength [9-10].

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Advances in Semiconductor Materials and Device Technologies

Fig. 2. Tauc plot for ZBVS2 glass Fig. 3. Variation of optical band gap with ZnSO4mol%

Urbach energy, ΔE is the reciprocal of the slope of Table 1 and lie in the range of 0.205 eV – 0.255 eV.
ln(α) versus hν plot (see Fig. 4) in the region of lower Further Urbach energies increase from 0.205 eV to
photon energy[16]. ΔE can give information about the 0.255 eV with increase in ZnSO4 concentration,
degree of disorder effects in amorphous systems [11- which is attributed to the increment in the defects,
12]. The increase in the values of ΔE of the materials disorderlyness and fragility of glasses [8]. The
is expected to have a greater tendency to convert increase in ΔE is also attributed to the reduction in
weak bonds into defects and degree of disruption the rigidity of the glass structure [13], which is in well
is high in glassy materials. The obtained values of agreement with the trends seen elastic properties of
ΔE for the investigated glasses are presented in the the investigated glasses.

Fig. 4. Urbach plot for ZBVS2 glass Fig. 5. Variation of refractive index with ZnSO4mol%

The refractive index of the glasses is estimated using polarization effect of oxide ions caused by Zn2+ ions

the expression [16] and are presented in the Table 1. whose cation polarizabilities are = 0.286 Å3

The refractive index, n lies in the range of 2.46 to [14]. The variation of refractive index n with ZnSO4
mol% is shown in Fig. 5. It can be noticed from Fig
2.63. The values are in agreement with the values
5 the refractive index of glasses increases with the
reported by Tasheva et al [6] for the B2O3 – BaO -
V2O5 glass system. The high values of the refractive addition of ZnSO4 content.
index in the present glasses have been attributed to the

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Advances in Semiconductor Materials and Device Technologies

As the ZnSO4 content increases, due to volume The estimated values of molar electronic polarizability
increasingeffect, it causes increase in bond- length
of borate and boro-vanadate structural units, are listed in the table.1 and the values are in the range
which in turn increases the refractive index and
the polarizability of glasses [7]. The variation of 5.83-6.10 Å3. The molar electronic polarizability
refractive index with optical band gap is shown in
Fig. 6 and it can be noticed that the refractive index increases with increasing concentration of ZnSO4.
linearly decreases with increase in optical band gap of The variation of molar electronic polarizability with
investigated glasses.
ZnSO4 mol% is shown in Fig. 7. This can be attributed
The values of molar refraction (Rm) are calculated by due to polarization effect of oxide ions caused by
using equation [16] and are presented in Table 1. The
molar refraction Rm for the glasses investigated lie Zn2+ ions whose cation polarizabilities are =
in the range of 14.70 to 15.38 cm3 and Rm increases
with increasing concentration of ZnSO4. The 0.286 Å3 [14]. Also the variation of molar electronic
average electronic polarizability is estimated from
the Lorentz-Lorenz expression by introducing the polarizability with refractive index is shown in Fig.
Avogadro’s number through the following expression
[15] given by 8. It can be noticed form the graph that the molar

electronic polarizability increases with refractive

index.

(1) The metallization criterion, M, which estimates the
metal/insulator behavior of the optical material is
Where NA is the Avogadro’s number corresponding calculated using equation 4.16 and the values are lie
to the number of polarizable ions per mole. The value in the range 0.372-0.336 is presented in the Table.1.
4π/3 is the constant which appear in Lorentz function. It can be noticed the metallization criterion, M,
The molar electronic polarizability estimates the decreases with increasing concentration of ZnSO4.
magnitude of electron response whenelectromagnetic That is when metallization criterion, M, decreases,
field is applied to the electron clouds. By expressing the metallic character of the solid increases and
αm in (Å3) the above equation can be simplified as insulating property decreases [14]. This improvement
in the metallic character can attributed to decrease in
the band gap as pointed out in earlier discussion which
occurs due to the weakening of network bonds due
to the addition of ZnSO4 to boro-vanadate network
structure. The variation of metallization criterion
with ZnSO4 content is shown in Fig.9

(2)

Fig. 6. Variation of n with optical band gap Fig. 7. Variation of αmwith ZnSO4mol%

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TABLE. 1 OPTICAL PARAMETERS OF ZINC-BORO-VANADATE GLASSES

Property ZBVS1 ZBVS2 ZBVS3 ZBVS4 ZBVS5

Indirect optical band gap (EopteV) 2.77 2.70 2.50 2.32 2.26
Urbach energy (ΔE eV) 0.205 0.218 0.233 0.247 0.255
Refractive index (n) 2.46 2.48 2.55 2.61 2.63
Molar refractivity (Rm cm3) 14.70 14.72 14.85 15.10 15.38
Molar electronic polarizability (αm Å3) 5.83 5.84 5.89 5.99 6.10
Metallization criterion (M) 0.372 0.367 0.354 0.341 0.336
Reflection loss (RL) 0.178 0.181 0.190 0.198 0.202
Electronic polarizability (αe Å3) 0.249 0.251 0.256 0.262 0.263

Fig. 8. Variation of αmwith n Fig. 9. The variation of M with ZnSO4mol%

4. Conclusion 5.83-6.10 Å3. The metallization criterion M decrease,
the metallic character of the solid increases
The optical absorption spectra of all glasses reveal and insulating property decreases when ZnSO4
concentration increased.
two bands at about 505 nm (19,802 cm-1) and 602
REFERENCES
nm (16,611 cm-1) are characteristic of vanadyl
1. Anna S, Kalbarczyk, Kalabinski J, Jan L, Nowinski,
(VO2+) ions in a tetragonal crystal field (C4V) of WioletaŚlubowska, MarekWasiucionek, Jerzy E,
distorted octahedral (Oh) sites and correspond to the Garbarczyk, Solid State Ionics, 271 (2015)10.
transitions 2B2g→2A1g and 2B2g→2B1g respectively.
The values of optical band gap decrease from 2.77 2. Maheshvaran K, Veeran P K, Marimuthu K, “Structural
and optical studies on Eu3+ doped boro- tellurite glasses”,
to 2.26 eV for indirect allowed transitions when Solid State Sciences, 17 (2013) pp. 54.

ZnSO4 concentration increased from 5 to 25 mol%. 3. Khattak G D, Tabet N, Wenger L E, Phys. Rev.,B 72 (10)
The decrease in band gap energy can be attributed to (2005) pp. 104-203.

the increase in degree of delocalization of electrons 4. Murugan G S, Fargin E, Rodrigues V, J. Non-Cryst
Solids,(3) (2004) pp. 158.
due to increasing concentration of larger SO42- ions
occupying the interstitial positions of the network 5. SumalathaB, Omkaram I, RajavardhanaRao T,
LingaRajuCh, “The effect of V2O5 on alkaline earth zinc
structure of boro-vanadate glasses. Urbach energies borate glasses studied by EPR and optical absorption”, J.
Mol. Struc., 1006 (2011) pp. 96-103.
increases form 0.205 eV to 1.255 eV. The

refractive index, n lies in the range of 2.46 to 2.63.

The values of electronic polarizability are in the range

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Advances in Semiconductor Materials and Device Technologies

6. Tina Tasheva, VesselinDimitrov, “Optical Properties and Hydrogenated Amorphous Silicon”, Phys. Rev. Lett.,
Structure of B2O3-BaO-V2O5 Glasses”, J. Chemical 47(1981)pp. 1480-1483.
Technology and Metallurgy, 50 (2015) pp. 441-448.
12. Hasan M A, Hogarth C A, “A study of the structural,
7. Saddeek Y B, Aly K A, Bashier S A, “Optical study of lead electrical and optical properties of copper tellurium oxide
borosilicate glasses”, Physica B, 405 (2010) pp. 2407– glasses”, J. Mater.Sci., 23 (1988)pp. 2500-2504.
2412.
13. Hajer S S, Halimah M K, Azmi Z, Azlan M N, “Optical
8. Faznny M F, Halimah M K, Azlan M N, “Effect of properties of zinc-boro-tellurite doped samarium”,
lanthanum oxide on optical properties of zinc borotellurite Chalcogenide Letters, 11(2014)pp. 553-566.
glass system”, J.Optoelectronics and Biomedical Materials,
8 (2016) pp.49 – 59. 14. Dimitrov V, Komatsu T, “An interpretation of optical
properties of oxides and oxide glasses in terms of the
9. Azmoonfa M, Hekmat-shoar M H, Mirzayi M, Behzad H, electronic ion polarizability and average single bond
“Optical properties of glasses in the Li2O–MoO3–P2O5 strength (review)”, J. Chem. Tech., Metallurgy, 45 (2010)
system”, Ionics, 15(2009)pp. 513-518. pp. 219-250.

10. Chimalawong P, Kaewkhao J, Kittiauchawal T, Kedkaew 15. Azlan M N, Halimah M K, Shafinas S Z, Daud W M,
C, Limsuwan P, “Optical Properties of the SiO2-Na2O- “Electronic polarizability of zinc borotellurite glass system
CaO-Nd2O3Glasses”, American J. Applied Sciences, 7 containing erbium nanoparticles”, Mater. Express, 5 (2015)
(2010) pp. 584-589. pp. 211- 218.

11. Cody G D, Tiedje T, Abeles B, Brooks B, Goldstein 16. N. Sivasankara Reddy, R. Viswanatha, R. P. S. Chakradhar,
Y, “Disorder and the Optical-Absorption Edge of C. Narayana Reddy, J. Alloys. Compd. 695 1368-1377
(2017).

 49

STRUCTURAL, THERMAL AND SPECTROSCOPIC
PROPERTIES OF ZIRCONIUM OXIDE INCORPORATED
SODIM BORATE GLASS

Roopa 1, B. Eraiah1*, A. Madhu1
1Department of Physics, Jnana Bharathi campus, Bangalore University, Bengaluru-560 056, India
1* Email:[email protected] *Email:[email protected]

Abstract was observed that the properties of borate glasses
modified with alkali oxides showed nonlinear
Zirconium oxide incorporated sodium borate behavior when the alkali oxide was gradually
glass samples have been prepared by conventional increased [2]. From the literature, The addition of
melt quenching technique and characterized low phonon energy (300-800 cm-1) (Zirconium) to
through thermal, structural and spectroscopic high phonon energy (1300-1500 cm-1), a relatively
measurements. Physical parameters of these high thermal stability, high chemical durability, high
glasses were also investigated. XRD pattern of viscous and ease of fabrication can be attained. It is
the prepared glasses confirms its amorphous also established that the inclusion of ZrO2 to silicate
nature. TGA-DTA measurements were made for glass matrix causes a substantial hike in the refractive
NBZ glasses to observe the mass change effects index, decreases the cut-off wavelength and reduces
during heating process. FTIR and RAMAN the photochromism of the glass [3, 4].
spectra exhibits several stretching/bending
vibration bands, sharp and weak bands which 2. Experimental
gives the information about the local structure of
the prepared glass samples. Upon the excitation In the present study, the glass system (x ranging from
365nm the PL studies were carried out as the 0 to 7 mol %) was chosen for investigation the Glass
absorption spectra shows a broad spectrum near Samples are labeled as NBZ0, NBZ1, NBZ3, NBZ5
365nm to know the possible transitions. and NBZ7 for 0 to7mol% Zr2+ ions respectively.
Initially compounds H3BO4, Na2CO3, ZrO2 are used in
Keywords: Zirconium oxide, FTIR, RAMAN, TG-DTA, the fabrication of glasses of AR grade quality. Batch
Photolumencence calculated compounds with respective gravimetric
factor involved were weighed with electrical balance
1. Introduction to an accuracy of 0.001g and then mixed thoroughly
in an agate mortar. The homogeneous mixture taken
Borate glass is one of the most characteristic glasses in porcelain crucible was kept in furnace at 1030-
having unique superstructure (SS) of intermediate 10400C for 40 min till a bubble free liquid was
range order (IRO) such as boroxol ring and tetra produced. The resultant melt was then transferred
borate. The conversion of three fold coordinated on a brass slab kept at room temperature to obtain
boron with the addition of modifier oxides is found solid pellets. The glass samples were annealed for 2
in short-range order (SRO) and becomes one of the hours at 3000C to remove the thermal and mechanical
main factors bringing about the variety of SS [1]. The stress. X-ray diffraction (XRD) measurements
ability of boron to exist in three- and four-oxygen were carried out using Rigaku Ultima IV, Cu-Ka
coordinate environments and the high strength of radiations (λ = 1.54 Å) with copper filters operating
covalent B–O bonds enable borate to form stable at 40 kV and 100 mA. Fourier Transform Infra-Red
glasses. Physical properties of borate glasses can spectroscope (FTIR) measurements were carried out
often be altered by the addition of a network modifier with resolution of 4cm-1 in the spectral range 400
to the basic constituent. The commonly used network cm-1 to 4000 cm-1 using Thermo Nicolet, Avatar 370
modifiers are the alkali and alkaline earth oxides. It

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following KBR pellet technique. For thermal studies, TGA (residual mass) and DTA plot of NBZ7
DTA/TGA analysis were carried out with nitrogen sample are depicted in Fig. 1 it is observed from
atmosphere in the temperature range 1000C to 8000C TGA curve that, significant mass loss only about
by increasing the ZrO2 in the range 0 to 7 % with the ~1% from room temperature to 8000C indicates
heating rate of 100C/min. The Raman spectra of NBZ that the thermal stability of NBZ glasses up to 800
glass have exhibited different bands & the variations oC [5]. Further, the glass transition temperature
in the relative intensity in the range of 200cm-1 to (Tg) and onset of crystallization temperature
2000cm-1 using MICRO785IDraman (ocean optics). (Tc) and (Tm) were estimated from DTA plot.
The luminescence spectra of the samples were Having known Tg and Tc, glass stability factor,
recorded at room temperature on Photon Technology ΔT =Tc - Tg is determined. The estimated values
International fluorescence spectrophotometer. of Tg, Tc and ΔT are found to be 4410C, 5500C
The polished glasses have been used for optical and 1090C respectively for NBZ0 glass sample.
and photoluminescence measurements. All the Similarly, Tg = 5600C, Tc = 5970C and ΔT =
measurement were carried out at room temperature. 370C for NBZ7 glass samples and it is seen
that, binary glass samples are added to ternary
3. Results and Discussion system shows decreasing ΔT, which results in
the increase instability of glass. Because ΔT is
a) Thermal Studies given more than 1000C. It is also found that, the
The thermal stability of the LPBT glasses was glasses having high stability factor. The values
of Tg, Tc ,Tm were tabulated.
studied using thermal analysis (TG-DTA). The

Table.1.

Sample Name Tg 0C Tc 0C ΔT 0C Tm 0C Mass loss %
NBZ0 441 550 109 799 22
NBZ1 412 519 107 636 14
NBZ3 480 579 99 835 6
NBZ5 489 581 92 805 1.5
NBZ7 560 597 37 851 1

Fig. 1. TG-DTA profile of NBZ0 Glass Sample

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b) FTIR and Raman Studies 450-460 cm-1 may be due to the presence of
Zr-O-Zr units. The Raman spectra NBZ glass is
The FTIR spectra, comprises six major bands as shown in Fig.3. which explores the information
shown in the Fig 2. Band in the range 1200-1600 about the vibrational mode frequencies of the
Cm-1 is due to asymmetric stretching relaxation glass. The Raman Spectra exhibit the following
of B-O bonds from the (BO3) triagonal units, bands at 1200-1600 cm-1 due to asymmetric B-O
band in the range 1230-1270 Cm-1 can be stretching vibrations in BO3 units[7], The
attributed to B-O Streching vibrations in (BO3) bands at 840-880 cm-1 due to B-O-B bending
units from boroxyl ring. Band in the range 400- Vibrations[8], and band 700-780 cm-1 due to the
800cm-1 may be due to various B-O-B bending presence of Zr-O-Zr (or) ZrO4 units[9]. Band in
modes in (BO3) & (BO4) units [6]. The band the range 280-320 cm-1 can be attributed to the
due to the presence of ZrO4 is observed in the several B-O-B bending modes in (BO3 & BO4)
range 700-710 Cm-1 due to the presence of Zr- units.
O-Zr Vibrations (or) ZrO4 and also in the range

Fig. 2. FTIR Spectra of NBZ Glasses Fig. 3. Raman Spectral Studies of NBZ series Glass

c) Photolumencence studies 400 to 700nm. Energy levels which produce
red upconversion emission at 696nm, 685nm
The Fig.4 shows the photoluminescence & orange emission at 580 to 610nm and Green
spectra of NBZ glass samples recorded at emission at 485 to 510nm also there is Broad
room temperature at the excitation wavelength hump in the region 410 to 425nm. This band is
corresponding to the transition 3F2-3P1 due to identified due to 3P1-3P0, P2-P1, G4- F3 , D2- F3,
Zr2+ ions. The spectrum of each glass exhibited S0- F2 transition of Zr2+ ions.
a broad emission band peaking in the region

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Fig. 4. Photoluminesence spectra of NBZ glasses.

4. Conclusion REFERENCES

Zirconium oxide incorporated sodium borate glass 1. T. Yano, N. Kunimine, S. Shibata, and M. Yamane, J, Non-
samples have been prepared by conventional melt Cryst. Solids, vol. 321,p.137, 2003.
quenching technique and characterized through
thermal, structural and spectroscopic measurement. 2. G. D. Chryssikos, M. S. Bitsis, J. A. Kapoidsis, and E. I.
XRD pattern of the prepared glass confirms its Kamitsos, J.of Non-Cryst Solids, vol. 217, p. 278, 1997.
amorphous nature. TGA-DTA measurements were
made for NBZ glasses, to observe the mass loss 3. Ch. Srinivasa Rao, I.V. Kitykb, T. Srikumara, G. Naga
during heating process and it shows good thermal Raju, V. Ravi Kumara, Y. Gandhi, N. Veeraiah, J. Alloys
stability, and also Tg, Tc and Tm were tabulated. and Compounds, 509 (2011) 9230,
FTIR and RAMAN spectroscopy has been used in
order to analyze the local structural peculiarities of 4. T. Srikumar, Ch.SrinvasaRao, Y.Gandhi, N.Venkatramaiah,
our samples, to identify the contributions of each V.Ravikumar, N.Veeraiah, J. Phy. and Chem. of Solids, 72
component on the structure and to point out the role (2011) 190.
of the ZrO4 (or) Zr-O-Zr on changing the structural
properties of Na2O:B2O3 glasses. PL studies were 5. Shuai Kang,Xue Wang,Wenbin Xu,Xin Wang, Dongbing
carried out as the absorption spectra shows a broad He,Lili Hu, Opt.Mater. 66 (2017) 28.
spectrum near 365nm to know the possible transitions.
6. E. Mansour, Journal of molecular structure, 1014 (2012) 1.

7. Ch. Srinivasa Rao, V.Ravikumar, T. Srikumar, Y, Gandhi,
N.Veeraiah,” J. of Non-Cryt Solids 357 (2011) 3094.

8. G. Venkataiah, C.K. Jayasankar, K. Venkata Krishnaiah, P.
Dharmaiah, N. Vijaya,optical materials 66 (2016) 28.

9. T. Srikumar , I.V. Kityk , Ch. Srinivasa Rao , Y. Gandhi
, M. Piasecki ,P. Bragiel , V. Ravi Kumar , N. Veeraiah,
Ceramics international, 37 (2011) 2763.

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OPTICAL AND PHYSICAL PROPERTIES OF SODIUM
CALCIUM LEADFLUORO BORATE GLASSES
INCORPORATED WITH PRASEODYMIUM ION

Susheela K. Lenkennavar1,2, Madhu. A1, B. Eraiah1, M.K. Kokila*
1 1Department of Physics, Bangalore University, Bengaluru -56, India
1,2Dept of physics, FMKMC College, Constituent College of Mangalore University,
Madikeri-571201, Karnataka, India 1,2E-mail:[email protected] *1E-mail:[email protected]

Abstract peculiarities such as low melting point, high optical
transparency, high chemical stability and good rare
In the present paper, the glass composition earth ion solubility. They are also found to be robust
20Na2O -10CaO-10PbF2 -60B2O3 doped with and inexpensive [1- 4]. But the addition of alkali/
varied concentrations of Pr3+ have been prepared alkaline earth oxide/fluoride converts the boron
using muffle furnace by the conventional coordination and the structural groups from one to
melt quenching technique and the impact of another depending on the type and concentration of
Praseodymium ions concentration on optical the alkali/alkaline earth oxide/fluoride. On the other
and physical properties of present glasses have hand, the high phonon energies (~1300-1500 cm-1)
been examined. The densities (ρ) of the glass possessed by borate glasses encourage non radiative
samples were measured using Archimede’s emission process very much and cannot acts as good
principle with toluene as an immersion liquid. laser host[5-8]. From this point of view, the fluoride
Refractive indices (n) of samples were measured compounds have less phonon energies (300–600
at 589.3 nm using an Abbe’s refractometer with cm−1) added to borate host as network modifiers,
mono- bromonaphthalene as the contact liquid can strongly reduce the phonon energies of borates
and few physical parameters of the glasses like, to a relatively lower values and even increases their
molar volume (Vm), molar refractivity (Rm), mechanical strength [9]. Moreover, the solubility of
polarizabilities (αm), concentration of rare earth RE ions is also larger in the fluoride medium than in
ion (Ni), polaron radius (rp) , inter ionic distance the oxide [10] and the fluoride compounds present
(ri), field strength(F), reflection loss (RL%) and in borates helps in reacting and removing the – OH
dielectric constant (ε), energy band gap and group from the borate glass. Over and above, the
urbach energy are also calculated and tabulated. fluoride compounds in a glass can reduce scattering
The Powder X-Ray diffraction analysis of the and dispersion losses, which are very much required
prepared samples confirms the amorphous nature for the construction of LEDs. Praseodymium doped
of the samples. The optical absorption spectra glasses find variety of practical applications such as
of polished samples have been recorded at solid lasers, fibre amplifiers in 1.3 μm region, optical
room temperature in the wavelength range 400nm fibres, up-converters [11]. Laser action in visible
-800nm using Perkin Elmer lambda-35 UV-Vis spectral region has been observed for the transition
spectrometer. Direct and Indirect band gaps are 1D2→ 3H4 of the Pr3+ ion. Laser transition 1G4→
calculated using Tauc’s plot. 3H5 observed at ~1.3 μm in Pr3+ doped glass fibres
has been found to be very promising transition for
Keywords: Sodium Borate Glasses, Optical Band developing fibre amplifier for communication in the
Gap, X Ray Diffraction, UV/Visible Spectroscopy second telecom window[12]. In the present work an
attempt is been made to observe the optical properties
1. Introduction upon the Pr3+ ions incorporated to sodium lead fluoro
borate glasses.
Among various optical glasses available, borates are
the most important glassy systems owing to their

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2. Experimental Methods values are 1/2 and 2 for direct and indirect allowed
transitions respectively. The absorption coefficient α
Oxide glasses with composition 20Na2O -10PbF2- (υ), in amorphous materials, in the optical region near
10CaO -60B2O3 -XPr2O3 with X=0, 0.1,0.3,0.5 the absorption edge at particular temperature, obeys
mol% were prepared using electric furnace by empirical relation known as, Urbach rule [15] given
the conventional melt quenching technique and by , Where, hυ is photon
designated as FC, FC01, FC03, FC05, respectively. energy, a0 is a constant and EU is the Urbach energy.
10g batch chemical compositions were weighted more The physical properties were determined using
accurately, mixed and grinded in an agate mortar. standard formulae [16] were also calculated and
Then compositions were taken in porcelain crucible tabulated.
melted in an electric furnace in the temperature
range of at 1030-10500C for 45 minutes (stirred 3. Results and Discussion
for homogeneous mixing) and quickly poured on a
preheated brass moulds to get pellet form samples. a) Physical Properties
The amorphous nature of samples was confirmed by
XRD measurements (Rigaku Ultima IV) using Cu-Ka The idea about the physical properties is
radiations (λ = 1.54 Å) with copper filters at 40 kV necessary to analyze the changes in the structure
and 100 mA. The densities of the glass samples are of the glass systems. The calculated physical
measured at room temperature by using Archimedes parameters of glass samples are enlisted in
principles, with toluene as the immersion liquid Table 1.The refractive index of the present glass
of density (0.866 g/cm3). The refractive indices matrix is higher (~1.65). From the literature it is
measurements were made by the Abbe’s refractometer found that, the glass higher density are rigid in
with mono-bromonaphthalene as the contact liquid. nature [17]. Also glass containing higher average
The optical absorption coefficient α (λ) of the samples molecular weight will have lesser in inter ionic
was calculated by using the following equation [13] distance values [18]. The decrease in inter ionic
distance in the present glasses with increase in
Where A is absorbance and d Pr3+ content indicates that the atoms are more
is thickness of the sample respectively. The optical tightly packed. Table.1.Physical parameters of
bandgap Eopt, defines the direct and indirect energy the glasses: Refractive index(n), density (ρ),
difference between valence and conduction band molar volume (Vm), molar refractivity (Rm),
of glasses, is obtained from the equation [8, 14] polarizabilities (αm), concentration of Rare
earth ion (Ni) , polaron radius (rp) , inter ionic
Where α is the absorption distance (ri), Field strength(F), Reflection loss
coefficient, hν is the incident photon energy, B is (RL%) and Dielectric constant (ε).
the electronic transition constant and the index n

Glass n ρ(g/cm3) Vm Rm αm Ni(×10^ rp ri (nm) F (×10 RL(%) ε
M.W(g) (cm3 (cm-3) (×10^- 20) (nm)
FC 1.624 3.315 89.04 26.86 9.48 3.759 -- -- -- -- 5.655 2.637
FC01 1.654 3.363 89.37 26.57 9.74 3.863 3.176 1.292 3.205 1.797 6.079 2.737
FC03 1.653 3.384 90.03 26.60 9.74 3.860 9.678 8.915 2.211 3.774 6.058 2.732
FC05 1.653 3.314 90.69 27.36 10.02 3.973 1.573 7.582 1.881 5.217 6.065 2.734

b) XRD Measurements hump between 400 and 550 without any sharp
crystallization peak confirms the amorphous
XRD profiles of glasses scanned at the rate of nature of the prepared samples.
20/min. for the 2θ values between 100 and 800
which is shown in Fig.1. The presence of a broad

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Fig 1. XRD spectra of glasses Fig.2. Absorption spectra in visible region of glasses

Absorption spectra transitions of Pr3+ ions. The 4 peaks at 443nm, 470nm,
482nm and 592nm are due to 3P2,3P1,3P0 and 1D2
The spectra in visible region are as shown in Fig.2. respectively from 3H4 ground state of Pr3+ions. As
For Pr3+ doped NPCB glasses. We can clearly the Pr3+ions are increased the intensity of the peak
observe inhomogeneous prominent 4 peaks due to 4f also increasing of FC glasses.

Fig. 3. Direct energy band gap Fig. 4. Indirect energy band gap Fig. 5. Urbach energy

Table 2: Optical Properties of glasses at different concentration of Pr3+

Glasses Direct bandgap energy, E Indirect bandgap Urbach energy, E
D(eV)) energy, E In(eV) U(eV)
FC 3.24 0.44
FC01 3.15 3.27 0.95
FC03 3.10 3.19 1.05
FC05 3.04 3.09 1.33
3.01

Direct(ED) and indirect band gap (EIn) shows with increasing Pr2O3 content and there by shifts the
decreasing in nature as concentration of Pr3+ ions is band edge to lower energies and in-turn lead to have
increased in glasses. The EU is found to be increasing
indicates that weak bonds is converted into defects a decrease in the Eopt values. The direct, indirect
as Pr3+ ions concentration is increased. This suggests
that the non-bridging oxygen ion content increases band gap and urbach energy is calculated as shown in

Fig.3,4 and 5 reported in Table.2.

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4. Conclusion Lokeswara Reddy, B.C.Jamalaiah, J. Lumin. 142 (2013)
128-134.
In the present work, Pr3+ doped FC glasses optical
properties were analysed and few physical properties 5. Arul Rayappan, K. Marimuthu, J. Phys. Chem. Solids 74
are also calculated. We can observe the 4 transition (2013) 1570-1577.
peaks of Pr3+ ions in glasses in UV-Vis region have
increasing intensity of peaks as the concentration 6. W.A. Pisarski, G. Dominiak-Dzik, W. Ryba-Romanowski,
is increased. The Tau’s plot results the direct and J. Pisarska, J. Alloys Compd. 451 (2008) 220-222.
indirect band gap to be decreased as the concentration
of Pr3+ ions is increased which concludes that the non- 7. J. Pisarska, R. Lisiecki, W. Ryba-Romanowski, G.
bridging oxygen ion content increases with increasing Dominiak-Dzik, W.A. Pisarski, J. Alloys. Compd. 451
Pr2O3 content and there by shifts the band edge to (2008) 226-228.
lower energies and in-turn lead to have a decrease
in the Eopt values. These glasses have increase in 8. C. Madhukar Reddy, N. Vijaya, B. Deva Prasad Raju,
Urbach energy therefore weak bonds are converted Spectrochim. Acta A 115 (2013) 297-304. 12. S. A. Pollack,
into defects as Pr3+ ions concentration is increased. D. B. Chang, J. App. Phys. 64 (1988) 2885-2893.
Few physical parameters like density, molar volume,
molar polarizbility and RI are also reported. 9. Lucca, M. Jacquemet, F. Druon, F. Balembois, P. Georges,
P. Camy, J. L. Doulan, R. Moncorge, Opt. Lett. 29 (2004)
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Notes

Notes

Notes




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