Hindawi Publishing Corporation
Advances in Materials Science and Engineering
Volume 2013, Article ID 278934, 4 pages
http://dx.doi.org/10.1155/2013/278934
Research Article
Dopant Concentration and Effective Atomic Number of
Copper-Doped Potassium Borate Glasses
I. Hossain,1,2 N. K. Shekaili,2 and H. Wagiran2
1
2
Department of Physics, Rabigh College of Science and Arts, King Abdul Aziz University, Rabigh 21911, Saudi Arabia
Department of Physics, Universiti Teknologi Malaysia, 81310 Skudai, Johor Darul Takzim, Malaysia
Correspondence should be addressed to I. Hossain; [email protected]
Received 5 May 2013; Revised 1 October 2013; Accepted 17 October 2013
Academic Editor: Achim Trampert
Copyright © 2013 I. Hossain et al. This is an open access article distributed under the Creative Commons Attribution License,
which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Copper-doped (0.5 mol%) and undoped potassium borate glasses have been prepared by the composition of (100-x)H3 BO3 +
xK2 CO3 , where 10 ≤ x ≤ 30 mol % by the traditional melting quenching method. The structural pattern of glasses with different
composition has been identified by X-ray diffraction (XRD). The glow curves were analysed to determine various characterizations
of the TLDs. Identification of the compositions and concentrations and effective atomic number of undoped and doped potassium
borate glass was carried out using scanning electron microscope analysis (SEM). The dopant concentrations are found to be
0.25 mol%, while Zeff are 11.42 and 10.48 for Cu-doped and undoped potassium borate glasses, respectively.
1. Introduction
Borate compounds have been widely studied due to their
features as glass formers and also on account of being very
advantageous materials for radiation dosimetry application
as discussed elsewhere [1, 2]. The main advantages of these
compounds are an effective atomic number which is very
close to that of human tissue (𝑍eff = 7.42), low cost, and
easy preparation. This fact leads to use some borates ideal
materials to develop medical and environmental dosimeter
as discussed by Rao et al. [3].
A number of researchers investigated the thermoluminescence (TL) properties of lithium tetraborate: Li2 B4 O7
(LTB) doped materials with different activators such as Mn
as discussed by Annalakshmi et al. [4] and Cu as discussed
by Corradi et al. [5]. Kinetic parameters of some tissue
equivalent TL materials were investigated “as discussed by
Kitis et al. [6]”. Calcium-doped and undoped borate glass
system for TL dosimeter were studied by Rojas et al. [2].
The electron paramagnetic resonance spectroscopy of the
Mn2+ and Cu2+ centers in the glasses with Li2 B4 O7 and
KLiB4 O7 compositions was investigated by Padlyak et al.
[7]. TL and optical absorption properties of neodymiumdoped yttrium aluminoborate and yttrium calcium borate
glasses were studied by Yoshimura et al. [8]. Recently, we
have investigated the high dose (range: 0.5–4.0 Gy) photon
irradiation response of K2 B4 O7 , Cu system, aiming to develop
new host materials for thermoluminescence dosimeter (TLD)
[9]. To date, to the best of our knowledge, no report has been
published on dopant concentration, effective atomic number,
and a TL study of copper-doped potassium borate glasses.
2. Experimental
2.1. Sample Preparation. The samples of potassium borate
and Cu-doped potassium borate glass were prepared by a melt
quenching technique. These five samples have been made
by mixing different compositions of potassium carbonate
(mole 10%, 15%, 20%, 25%, and 30%) and boric acid (mole
90%, 85%, 80%, 75%, and 70%) after they were weighed. The
mass of each sample was measured using an electronic balance (PAG, Switzerland). The best copper-dopped potassium
borate glasses was formed using potassium borate samples
(mole 20% potassium carbonate and mole 80% boric acid)
and doped with 0.5 mole% of pure copper (Cu). Before the
melting process, the powders were mixed and homogenized
by milling the powders for 30 minutes. Then, the samples
Advances in Materials Science and Engineering
10
Intensity (a.u.)
Intensity (a.u.)
2
20
30
40
50
60
70
80
2𝜃
Figure 1: XRD pattern of composition [10%K2 CO3 + 90%H3 BO3 ],
polycrystalline.
(undoped) were melted in an alumina crucible in an electric
furnace at a temperature of 1000∘ C for 30 minutes depending
on composition until a clear homogenous melt was obtained.
The Cu-doped potassium borate samples were prepared
by using high temperature furnace with a temperature of
1200∘ C for 30 minutes. Then the molten samples were poured
onto a steel plate into another furnace to be annealed at a
temperature of 300∘ C for 3 hours. This furnace was used
with a different temperature for melting. The samples were
left to be cooled inside the furnace until they reached room
temperature to avoid thermal stress.
2.2. Annealing and Exposure to Radiation. In the current
investigation a Perspex sheet (tough transparent plastic material) contains 100 wells was covered by a thick black cover
to avoid any light signal during transportation and storage
or ultraviolet radiation from sunlight which can give rise to
the TL signal. Finally the Perspex sheet which contains the
Cu-doped and undoped potassium borate glass all together
was placed on the beam axis at a depth of 10 cm in a solid
phantom. The glass samples were exposed to 6 MV photon
irradiation emitted from Linear Accelerator (LINAC) Primus
MLC 3339 provided by the Department of Radiotherapy and
Oncology, Hospital Sultan Ismail, Johor Bahru, Malaysia. The
beam field size was set to 10 × 10 cm2 and placed at the
standard source surface distance (SSD) of 100 cm. The dose
delivered by LINAC machine was 20 to 400 MU (Monitor
Unit) using a constant dose rate of 200 MU/min. Each 50 MU
dose is equivalent to 0.5 Gy and it took 15 seconds for
complete exposure. The readout of the dosimeters was done
24 hours after irradiation. This period of time is very useful
to eliminate the lower traps deliberately and also allows time
for the lower energy thermoluminescence to decay away. The
TL response was read out by using TLD Reader 4500 in
Ibnu Sina Institute. The preheat temperature was 50∘ C for
10 seconds and the used readout temperature was 300∘ C for
33 seconds with a heating rate of 25∘ C S−1 and finally an
annealing temperature of 300∘ C was applied for 10 seconds
[9]. Consequently, the characteristics of TLD were discussed
and analyzed as follows.
10
20
30
40
50
60
70
80
2𝜃
Figure 2: XRD pattern of composition [30%K2 CO3 + 70%H3 BO3 ],
glass sample.
3. Results and Discussions
3.1. X-Ray Diffraction (XRD) Analysis. In this experiment,
XRD technique has been done for all the different compositions of samples previously prepared of undoped potassium
borate. The measurements were carried out using Siemens
Diffractometer D5000 system to analyze the structure of
the samples whether amorphous or crystalline state. Two
samples composed of 90% H3 BO3 (boric acid) + 10% K2 CO3
(potassium carbonate) and 85% H3 BO3 (boric acid) + 15%
K2 CO3 (potassium carbonate) are firmly crystalline by XRD
analysis. Figure 1 shows XRD pattern of polycrystalline by
the composition of 90% boric acid and 10% potassium
carbonates. On the other hand the XRD analysis showed that
the other three samples which are composed of 80% boric
acid and 20% potassium carbonate; 75% boric acid and 25%
potassium carbonate; 70% boric acid and 30% potassium
carbonate are glasses since there are broad peaks appearing
on the spectra pattern as shown in Figure 2.
3.2. TL Glow Curve. Thermoluminescence light emission
which is known as the thermoluminescence glow curve is
defined as the intensity of luminescence as a function of
temperature, which is possible to exhibit several maxima.
This glow curve varies with the mode of heating and heating
temperature. The area under the curve represents the radiation energy deposited.
Figures 3 and 4 present the glow curve for Cu-doped and
undoped potassium borate glass. The red line which appears
in the graph is the readout temperature which represents
300∘ C from the time-temperature profile set up for the
TLD reader. It is clear that the glow curve of Cu-dopped
potassium borate glasses is better than undoped potassium
borate glasses.
3.3. Scanning Electron Microscope Analysis (SEM). Scanning
electron microscope (SEM) technique has been done for
all the three different compositions of the glass samples
which were characterized by the XRD. The measurements
were carried out to identify the real composition of the
materials in the glass samples and to detect if there is any
Advances in Materials Science and Engineering
3
600
500
50.0
400
40.0
300
30.0
200
20.0
100
10.0
0.0
50
100
Channel
Table 2: Identification of the compositions and concentrations of
Cu-doped potassium borate glass by SEM.
Temperature (∘ C)
Intensity (nA)
60.0
0
200
150
Element
BK
OK
KK
Cu K
Total
Weight %
51.85
32.34
14.64
1.17
100
𝑊𝑖
0.5185
0.3234
0.1464
0.0117
1.0
At%
66.52
28.04
5.19
0.25
100
𝑍
5
8
19
29
𝐴𝑤
10.811
15.999
39.098
63.546
𝐴 𝑤 : the atomic weight, 𝑍: the atomic number of the element, 𝑊𝑖 : the
fractional weight, and At%: the atomic percentage.
Figure 3: The glow curve for the Cu-doped potassium borate glass
following 6 MV photon irradiations.
Intensity (nA)
500
400
2.0
300
200
1.0
100
50
100
Temperature (∘ C)
600
3.0
0.0
found to be 0.25 mol% as shown in Table 2. The effective
atomic number of undoped glass was found to be 10.48 by
the following formula:
0
200
150
Channel
Figure 4: The glow curve for the undoped potassium borate glass
following 6 MV photon irradiations.
Table 1: Identification of the compositions and concentrations of
undoped potassium borate glass by SEM.
Element
BK
OK
KK
Total
Weight %
26.24
61.51
12.25
100
𝑊𝑖
0.2623
0.6151
0.1225
1.0
𝑍
5
8
19
𝐴𝑤
10.811
15.999
39.098
36.546
𝐴 𝑤 : the atomic weight, 𝑍: the atomic number of the element, and 𝑊𝑖 : the
fractional weight.
other contaminated material which may affect the glass
samples. The result showed that all the glass samples were
contaminated by either silica (SiO2 ) or alumina (AL2 O3 ) or
both except the third glass which was composed of 80%
boric acid + 20% potassium carbonate. Table 1 shows the
actual composition of the glass sample. The former glass
samples were chosen to be doped with copper (Cu) in order to
study its TLD characterization. SEM technique also has been
done for the Cu-doped potassium borate glass to identify the
elemental compositions of the sample and the concentration
of each composition as shown in Table 2.
3.4. Dopant Concentration in Mol% and 𝑍eff . The SEM
technique was used to determine the dopant concentration.
The dopant concentration of copper (Cu) on the Cu-doped
potassium borate glass was presented by At% which was
1/𝑚
(𝑍eff ) 𝑍eff = (𝑎1 𝑍1𝑚 + 𝑎2 𝑍2𝑚 + 𝑎3 𝑍3𝑚 + ⋅ ⋅ ⋅ + 𝑎𝑛 𝑍𝑛𝑚 )
, (1)
where 𝑎1 , 𝑎2 , 𝑎3 , . . . 𝑎𝑛 are the weight fraction contributions
of each element in the glass depend on the total number
of electrons in the mixture and 𝑍𝑛 is the atomic number of
the element-𝑛. The value of 𝑚 adopted for photon purposes
is 2.94. Moreover the Cu-doped potassium borate glass was
found to have 𝑍eff = 11.42. This study indicates that
the effective atomic numbers of Cu-doped and undoped
potassium borate glasses were higher than the soft tissue
which is 7.4. These results indicated that Cu-doped and
undoped potassium borate glasses were not tissue equivalent.
4. Conclusions
Out of five different compositions, we have found three glass
samples composed of 80% boric acid and 20% potassium
carbonate; 75% boric acid and 25% potassium carbonate; 70%
boric acid and 30% potassium carbonate by XRD technique.
The glow curve of Cu-doped potassium borates glass is better
than undoped sample. The effective atomic numbers are
11.42 and 10.48 for Cu-doped and undoped potassium borate
glasses, respectively, which are higher than 𝑍eff in soft tissue
7.4. The Cu-doped potassium borate glass has been evaluated
to have dopant concentration of 0.25 mol% and this dopant of
Cu-doped glass has the capability of producing luminescence
as well as good TL response on irradiation.
Acknowledgments
This work was funded by the Deanship of Scientific Research
(DSR), King Abdulaziz University, Jeddah, Saudi Arabia,
under Grant no. 662-010-D1433. The authors, therefore,
acknowledge DSR technical and financial support. The
authors would like to thank Mr. Hasan Ali, Hospital Sultan
Ismail, Johor Bahru Malaysia, for helping in performing the
irradiations and Universiti Teknologi Malaysia (UTM) for
providing research facilities.
4
References
[1] M. Santiago, C. Grasseli, E. Caselli, M. Lester, A. Lavat, and
F. Spano, “Thermoluminescence of SrB4 O7 :Dy,” Physica Status
Solidi A, vol. 185, no. 2, pp. 285–289, 2001.
[2] S. S. Rojas, K. Yukimitu, A. S. S. de Camargo, L. A. O. Nunes,
and A. C. Hernandes, “Undoped and calcium doped borate
glass system for thermoluminescent dosimeter,” Journal of NonCrystalline Solids, vol. 352, no. 32–35, pp. 3608–3612, 2006.
[3] G. V. Rao, P. Y. Reddy, and N. Veeraiah, “Thermoluminescence
studies on Li2 O-CaF2 -B2 O3 glasses doped with manganese
ions,” Materials Letters, vol. 57, no. 2, pp. 403–408, 2002.
[4] O. Annalakshmi, M. T. Jose, and G. Amarendra, “Dosimetric
characteristics of manganese doped lithium tetraborate - An
improved TL phosphor,” Radiation Measurements, vol. 46, no.
8, pp. 669–675, 2011.
[5] G. Corradi, V. Nagirnyi, A. Kotlov et al., “Investigation of
Cu-doped Li2 B4 O7 single crystals by electron paramagnetic
resonance and time-resolved optical spectroscopy,” Journal of
Physics, vol. 20, Article ID 025216, 2008.
[6] G. Kitis, C. Furetta, M. Prokic, and V. Prokic, “Kinetic parameters of some tissue equivalent thermoluminescence materials,”
Journal of Physics D, vol. 33, p. 1252, 2000.
[7] B. V. Padlyak, W. Wojtowicz, V. T. Adamiv, Y. A. V. Burak,
and I. M. Teslyuk, “EPR spectroscopy of the Mn2+ and Cu2+
centres in lithium and potashium-lithium tetroborate glasses,”
Acta Physica Polonica A, vol. 117, p. 112, 2010.
[8] E. M. Yoshimura, C. N. Santos, A. Ibanez, and A. C. Hernandes, “Thermoluminescent and optical absorption properties of
neodymium doped yttrium aluminoborate and yttrium calcium
borate glasses,” Optical Materials, vol. 31, no. 6, pp. 795–799,
2009.
[9] I. Hossain, N. K. Shekali, and H. Wagiron, “Thermoluminescence response of copper-doped potassium borate glasses subjected to 6 Megavolt photon irradiation,” subjected to Journal of
Applied Spectroscopy.
Advances in Materials Science and Engineering
Journal of
Nanotechnology
Hindawi Publishing Corporation
http://www.hindawi.com
Volume 2014
International Journal of
International Journal of
Corrosion
Hindawi Publishing Corporation
http://www.hindawi.com
Polymer Science
Volume 2014
Hindawi Publishing Corporation
http://www.hindawi.com
Volume 2014
Smart Materials
Research
Hindawi Publishing Corporation
http://www.hindawi.com
Journal of
Composites
Volume 2014
Hindawi Publishing Corporation
http://www.hindawi.com
Volume 2014
Journal of
Metallurgy
BioMed
Research International
Hindawi Publishing Corporation
http://www.hindawi.com
Volume 2014
Nanomaterials
Hindawi Publishing Corporation
http://www.hindawi.com
Volume 2014
Submit your manuscripts at
http://www.hindawi.com
Journal of
Materials
Hindawi Publishing Corporation
http://www.hindawi.com
Volume 2014
Journal of
Nanoparticles
Hindawi Publishing Corporation
http://www.hindawi.com
Volume 2014
Nanomaterials
Journal of
Advances in
Materials Science and Engineering
Hindawi Publishing Corporation
http://www.hindawi.com
Volume 2014
Journal of
Hindawi Publishing Corporation
http://www.hindawi.com
Volume 2014
Journal of
Nanoscience
Hindawi Publishing Corporation
http://www.hindawi.com
Scientifica
Hindawi Publishing Corporation
http://www.hindawi.com
Volume 2014
Journal of
Coatings
Volume 2014
Hindawi Publishing Corporation
http://www.hindawi.com
Crystallography
Volume 2014
Hindawi Publishing Corporation
http://www.hindawi.com
Volume 2014
The Scientific
World Journal
Hindawi Publishing Corporation
http://www.hindawi.com
Volume 2014
Hindawi Publishing Corporation
http://www.hindawi.com
Volume 2014
Journal of
Journal of
Textiles
Ceramics
Hindawi Publishing Corporation
http://www.hindawi.com
International Journal of
Biomaterials
Volume 2014
Hindawi Publishing Corporation
http://www.hindawi.com
Volume 2014