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Published by SIDEK BIN HJ AB AZIZ / FS, 2019-11-10 10:57:33

SAA - UV Vis Sm Glass Ceramic 001A purple

SAA - UV Vis Sm Glass Ceramic 001A purple

7th International Conference on Solid State Science and Technology (7th ICSSST 2019)

November 11-13, 2019, Everly Hotel, Putrajaya Malaysia

UV-VIS SPECTROSCOPY OF SAMARIUM DOPED WOLLASTONITE
- CaSiO3:Sm3+

Sidek Ab Aziz, Karima AlMasri,

Mohd Hafiz Mohd Zaid, Khamirul Amin Matori
Department of Physics, Faculty of Science

Universiti Putra Malaysia, 43400 UPM Serdang, Selangor

 Introduction

 A batch of prepared glass was mixed with CaO and Sm2O3 in
a composition ratio of [(SLS)0.79(CaO)0.21]1-y[Sm2O3]y where y
=(0,1,2,3,4,5) mol%, and specimens were then blended by
using regular melt-quenching method.

 Melting and quenching technique followed by conventional
solid state method is used in order to produce wollastonite-
based glass ceramics.

 Calcium Silicate acquires a higher luminous efficiency when it
is doped with rare earth activated ions due to their thermal
stability, high temperature strength, low thermal expansion
and chemical inertness.

PROBLEM STATEMENT OBJECTIVES

➢Over the last few years, the optical  To synthesis wollastonite doped samarium
researches on rare earth doped glasses oxide based glass-ceramics by using
draw much attention due to their wide conventional melt quenching method
applications in optical areas such as followed by sintering method.
optical switches for laser, sensors, and
optical communications.  To study the effect of different sintering
➢The most important concerns in rare earth temperatures on the physical, structural,
doped glasses are to define the dopant and optical characteristics of wollastonite
effect to the host materials . based glass-ceramics.
➢ Recently, there are not much work had
been done on wollastonite glass and only a  To examine the effect of Sm3+ doping on
few studies have been published on it, and the physical, structural, and optical
none with samarium oxide. characteristics of wollastonite based glass-
ceramics.

LITERATURE REVIEW

RESEARCH FINDINGS AUTHOR

Performances of • Dense wollastonite ceramic was produced by SPS. Xianghui
et al
CaSiO3ceramic sintered Amorphous wollastonite crystallized to wollastonite 2M firstly, (2008)
then, transformed to pseudowollastonite.
by Spark • The grain sizes of wollastonite increase slowly at lower
plasma sintering
sintering temperature (from1100 °C to 1150 °C) and then

rapidly at higher sintering temperatures (from 1150 °C to 1200

°C).

• While the relative density, increase rapidly at lower sintering

temperature and then slowly at higher sintering

temperatures

Synthesis, • PXRD patterns reveal monoclinic CaSiO3 phase can be at Nagabhush
characterization and et al
photoluminescence 900 ◦C. (2011)
properties of CaSiO3: • SEM micrographs show the crystallites with irregular shape,
Eu3+ red phosphor
mostly angular.
• The UV–vis absorption of undoped and doped phosphor

show an intense absorption band at 240–270 nm.
• The optical band gap is less in undoped sample when

compared to Eu3+ doped CaSiO3

LITERATURE REVIEW

RESEARCH FINDINGS AUTHOR

Low temperature • The α-wollastonite phase was fully obtained at a Rashid et al
production of limestone/silica sand molar ratio of 1:1, sintered at (2014)
wollastonite from 1450 ◦C for 4 h, with a dense microstructure and
limestone and olivine as a minor phase.
silica sand
through solid-state • Purity of the raw materials, molar ratio of
reaction limestone/silica sand and firing temperature all had an
influence on the final product of calcium silicate
materials

Characteristic of • wollastonite (CaSiO3) has been synthesized from local raw Shukur et al
Wollastonite (2014)
Synthesized from materials by solid state method at different temperatures. Low
Local Raw temperature wollastonite (β- CaSiO3) was achieved at 1050◦C
Materials
with a density of 1.75 g/cm3.

• As the temperature increased to 1150◦C, pseudowollastonite can be

observed and continued its crystallization up to 1250 ◦C with a

maximum density of about 1.98 g/cm3. Linear thermal expansion

for samples sintered at 1050 ◦C is more compatible with natural

wollastonite

METHODOLOGY

Sample preparationcleanin crushin grindin sievin powde
g g g r
g

❖ SLS glass powder

Weighting 1 Milling 24 2 0MCel˚t)in2gh(o1u40rs3 Crushing & 6 Sieving 7 Powder 8
(CaO-SLS- hours pressing -
grinding
Sm2O3)
pellet
2

Quenching in4 hoDurrys iangt ro24om5 Sintering at 9
water different
temperature temperatures

RESULTS & DISCUSSION

Analysis and X-RAY X-RAY Fluorescence(XRF)
Measureme Fluorescence(XRF)
Chemical composition of SLS
nts X-RAY
diffraction(XRD) and precursor glass.

The Fourier SiO2 CaO Na2O Fe2O3 SiO2 CaO Na2O Fe2O3
transform
infrared 58.0 27.0 12.0 1.5
spectroscopy
Dens(FitTyI-RF)ESEM CaO-SLS SiO2 CaO Na2 Fe2O K2O Others
glass O
UV-VIS (Optical 51.0 44.0 3 0.3 0.2
band gap) compositio 3.8
n (%) 0.7

 DENSITY

2.82

2.815

Density (g/cm3)2.81 ❖ Density increases up to 4 mol % of Sm2O3 then
2.805 suddenly drops at 5 mol % of Sm2O3.

2.8 ❖ This indicates that by addition of small amount of
2.795 Sm2O3 in to CaO-SiO2 glass network, initially it may
resist the creation of non-bridging oxygen so the
2.79 density increases.
2.785
❖ With further increase in Sm2O3 concentration, the
2.78 creation of non-bridging oxygen takes place so the
2.775
density drops at 5 mol% of Sm2O3.
0123456
mol% of Sm2O3 Sm2O3 undoped 1% 2% 3% 4% 5%

Variation in density of samples sintered at Density(g/ ) 2.780 2.78 2.791 2.802 2.81 2.80
1000°C versus Sm2O3 concentration. 5 50

 DENSITY

❖ During crystallization, re-adjustment of particles occurs as viscosity

increases, sintering occurs in viscous flow, and the particles were

joined via sintering necks.
❖ Since it has little effect in decreasing the pore size of the glass-

ceramic samples, the result is growth of grains and increased

densification.
❖ Sintering also causes the precursor glass to release stress,

which could result in a reduction in average interatomic
spacing. The reduction in interatomic spacing plays a
role in increasing density as sintering temperature
increases.

Variation in density of undoped sample Temperature 700 800 900 1000 1100
versus sintering temperatures. C˚

Density(g/ ) 2.65 2.680 2.730 2.780 2.820
0

FTIR ❖ There are two broad bands at ~460 cm-1 and ~880 cm-1. The silica

undoped existing in SLS glass powder contributed to both infrared absorption
1 wt. %
2 wt. % bands.
3 wt. % ❖ The bands at ~460 cm-1 may be ascribed to the Si-O-Si bending
4 wt. %
5 wt. % mode. The data from FTIR analysis shows that only minor
changes occurred when a transition metal was
Transmittance (a.u.) introduced into the glass system. Absorption within the
425-600 cm-1 range may be ascribed to the Si-O
400 800 1200 1600 2000 2400 2800 3200 3600 4000 vibration.
Wavenumber (cm-1) ❖ The bands at 711 cm-1 may be ascribed to the Si-O-Si
symmetric stretching vibrational mode. Si-O vibration is
responsible for the absorption bands occurring at 1010
cm-1 .
❖ No change was observed in the location or intensity of
absorption bands of Sm3+ (1–5 mol %) doped CaSiO3
which proved that the dopant did not alter its phase and
crystallinity. These results are congruous with the findings
of a study carried out by Manjunatha et al. (2013).

FTIR spectra of undoped and Sm+3 doped SLS-CaO based
glass sintered at 1000 ˚C.

FTIR ❖ FTIR spectra of samples within the range of 400 and
4000 cm-1 which were sintered at varying
27 ⁰C temperatures. The bands in the low frequency (400-
700 ⁰C 600 cm-1) range can be ascribed to Si-O vibration
800 ⁰C (Nagabhushana et al., 2011).
900 ⁰C
1000 ⁰C ❖ The mid-frequency band between t 600-800 cm-1 can
1100 ⁰C

Transmittance (a.u.) be ascribed to the symmetric stretching vibrations of

both Si-O and Si-O-Si bond bending, while the high-

frequency bands within the spectral range of 800-1250

cm-1 can be ascribed to the asymmetric stretching

modes of Si-O inwards the SiO4 tetrahedron.

❖ The data from the FTIR analysis validates that the IR

bands at 470, 508, 650, 905 and 1020 cm-1 are a result

of the wollastonite phase (Atalay et al., 2001). The

bands in the 1460 cm-1 span of the sample indicate

the presence of CaO in the structure of the sample.

❖ Samples sintered at higher temperature contains

400 800 1200 1600 2000 2400 2800 3200 3600 4000 higher amounts of β-CaSiO3, resulting in the bands
Wavenumber (cm-1) becoming more intensive. The FTIR measurements

basically conform with the results of the XRD and

prove that wollastonite began to crystallize at 800 ⁰C

FTIR spectra of undoped sample sintered at varying temperatures. and that the crystallinity of wollastonite are improved
with higher sintering temperatures.

XRD w = wollastonite ❖ It can be noticed that the
corresponding planes for the major
w diffraction peak can be indexed
using the standard diffraction pattern
Intensity (a.u.) for the CaSiO3 crystal phase.

❖ Also it can be noticed that there are
no changes in crystal phases when
increase the ratio of samarium oxide.

undoped
1 wt. %
2 wt. %
3 wt. %
4 wt. %
5 wt. %

0 10 20 30 40 50 60 70 80 90



XRD patterns for samples with varying ratios of Sm2O3

sintered at 1000˚C.

XRD

w

ww w

w w w w ww w w ww ww w w w
w
❖ XRD confirms the amorphous generation of
Intensity (a.u.) w = wollastonite soda lime silicate glass prior to sintering.
Increasing sintering temperature to 800 °C
(CaSiO3) causes the nucleation of the triclinic
N = nepheline wollastonite (CaSiO3) phase.

(NaAlSiO4) ❖ Para wollastonite (β-CaSiO3) phase,
together with a little nepheline (NaAlSiO4)
NN phase, are formed at 900 ⁰C.
N
❖ At 1000 ⁰C relative intensities of the
27 °C crystalline peaks in the samples improved,
700 °C which can be clearly seen in the β-CaSiO3.
800 °C At 1100 ⁰C resulted in an improvement in
900 °C the crystallinity of the glass-ceramic
1000 °C samples.
0 10 20 30 40 50 60 70 80 90


XRD patterns of undoped samples sintered at varying
sintering temperatures.

Optical band gap

❖ The optical band gap of the Sm2O3 Band gap
specimens increase as the (eV)
fraction of samarium oxide was undoped
increased. 1% 4.12
2% 4.2
❖ This shows that inter-band 3% 4.24
transitions in the undoped and 4% 4.28
doped specimens are due to 5% 4.27
the allowed direct transitions. 4.36

❖ These results conform with those
presented in the literature
(Manjunatha et al., 2013). The
undoped samples have lower
optical band gap that that of
the Sm3+ doped CaSiO3.

Plot of (αhv)2 versus photon energy (hv) for undoped and Sm3+
doped CaSiO3 based glass-ceramic sintered at 1000 °C.

Optical band gap ❖ Basically, as sintering

Plot of (αhv)2 versus photon energy (hv) for undoped and Sm3+ temperature was gradually
doped CaSiO3 based glass-ceramic sintered at 1000 °C.
increased, the sizes and number

of the crystals formed also

increased. Hence, the centers of

❖ The energy band gap for the scattering decreased; this proves
that the energy band gap for the

sample sintered at varying samples have increased.

sintering temperature were Additionally, the shift in energy

determined by deducing the band gap is more likely with

linear region to zero. The regard to structural

values for energy band gap rearrangements (Henriques et al.,

increased as the sintering 2006).

temperature was raised

gradually. Temperatur Band gap
❖ It can be concluded that as e (eV)

the sintering temperature was (C˚) 4.12
increased, the energy gap
increases as a result of the 700

direct allowed transition. The 800 4.2

increasing trend of energy 900 4.24
band gap can be ascribed to 1000 4.28
the scattering of short

wavelength light by the 1100 4.27

crystals.

FE-SEM analysis

Sm2O3 Grain size(nm)

undoped 1% Sm3+ 2% Sm3+ undoped 24.2
1% 24.310
2% 24.482
3% 25.331
4% 25.824
5% 26.101

❖ The FESEM results show a

uniform distribution of particles

and the morphology is

agglomerated in spherical

shapes.
❖ The grain sizes increase as the

amount samarium oxide was

3% Sm3+ 4% Sm3+ 5% Sm3+ increased (Manjunatha et al.,
2013).

FESEM micrographs of undoped and Sm3+ doped with varying ratios of CaSiO3
sintered at 1000⁰C

FE-SEM analysis

700⁰C 800⁰C 900⁰C ❖ Based on the FESEM

Temperatu Grain measurements, the glassy
re size(nm) surface is located at 700 ⁰C.
(C˚) ❖ Triclinic wollastonite crystal
21.318
800 22.911 grains began to form at 800
⁰C. with raising the heat
900 24.2
26.602 treatment temperature to 900
1000 ⁰C and higher, the

1100 morphology of the crystal of

1000⁰C 1100⁰C para wollastonite became

FESEM micrographs of undoped specimens sintered at varying relict shaped granular crystals
temperatures.
with identical distribution.
❖ The microstructure of the

samples at temperatures
exceeding 1000 ⁰C can be

attributed to the monoclinic

para wollastonite crystal

phase. Additionally, the

average grain increasing

slightly as the sintering

temperature increase.

CONCLUSION

❖ Wollastonite has been ❖ XRD confirms the amorphous
synthesized from recycled generation of soda lime silicate glass,
SLS glass by using solid triclinic wollastonite (CaSiO3) phase
state method. formed at 800 °C, Para wollastonite (β-
CaSiO3) phase, together with a little
❖ The density of the sintered nepheline (NaAlSiO4) phase, are
samples increased with formed at 900 ⁰C. At 1000 ⁰C relative
higher sintering intensities of the crystalline peaks in
temperature and higher the samples improved, which can be
Sm3+ concentration. clearly seen in the β-CaSiO3. At 1100
⁰C resulted in an improvement in the
❖ The proportion of SiO2 and crystallinity of the glass-ceramic
Al2O3 in waste materials samples. Also it can be noticed that
determines their glass there are no changes in crystal phases
forming potential since when increase the ratio of samarium
these elements may oxide.
dominate the constitution
of the vitreous matrix of a ❖ UV-Vis spectroscopy shows that
glass product. intensive absorption occur in the UV
region, between of 250-390 nm. The
values of energy band gap increased

CONCLUSION

❖ Based on the FTIR results, the ❖ Based on the FESEM
bands in the low frequency measurements, the glassy
(400-600 cm-1) range can be surface is located at 700 ⁰C.
ascribed to the Si-O Triclinic wollastonite crystal
vibration. The bands within grains began to form at 800
the mid-frequency range of ⁰C. at 900 ⁰C and higher,
600-800 cm-1 ascribed to the morphology of the
both the symmetric crystal of para wollastonite
stretching vibrations of Si-O became relict shaped
and the Si-O-Si bond granular crystals with
bending, while those within identical distribution. The
the high-frequency range of microstructure of the
800-1250 cm-1 ascribed to samples at temperatures
the asymmetric stretching exceeding 1000 ⁰C can be
modes of Si-O inwards the attributed to the monoclinic
SiO4 tetrahedron. The bands para wollastonite crystal
at 1460 cm-1 indicate the phase. Additionally, the
presence of CaO in the average grain increasing
sample structure. These slightly as the sintering
bands decreased as the temperature increase. The
sintering temperature grain sizes increase as the
increased. The infrared
spectra of undoped SLS-
CaO and SLS-CaO doped

REFERENCES

 Yoon, S. D., Lee, J. U., Lee, J. H., Yun, Y. H., & Yoon, W. J. (2013).
Characterization of wollastonite glass-ceramics made from waste
glass and coal fly ash. Journal of Materials Science &
Technology, 29(2), 149-153.

 Eraiah, B. (2006). Optical properties of samarium doped zinc-tellurite
glasses. Bulletin of Materials Science, 29(4), 375-378.

 Matori, K. A., Zaid, M. H. M., Sidek, H. A. A., Halimah, M. K., Wahab, Z.
A., & Sabri, M. G. M. (2010). Influence of ZnO on the ultrasonic
velocity and elastic moduli of soda lime silicate glasses. International
Journal of Physical Sciences, 5(14), 2212-2216.

 Ismail, H., Shamsudin, R., & Hamid, M. A. A. (2016). Effect of
autoclaving and sintering on the formation of β-
wollastonite. Materials Science and Engineering, C (58), 1077-1081.

 Shukur, M. M., Al-Majeed, E. A., & Obied, M. M. (2014). Characteristic
of wollastonite synthesized from local raw materials. Int. J. Eng.
Technol, 4(7), 426-429.

 Henriques, J. M., Caetano, E. W. S., Freire, V. N., Da Costa, J. A. P., &
Albuquerque, E. L. (2006). Structural and electronic properties of
CaSiO3 triclinic. Chemical physics letters, 427(1), 113-116.

 Holland, W., & Beall, G. (2002). Glass–Ceramic Technology.
American ceramic society. Westerville, OH.


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