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New chalcohalide glasses from the Sb2S3-MXn system
] O U R N A L OF
ELSEVIER
Journal of Non-Crystalline Solids 184 (1995) 1-4
New chalcohalide glasses from the
Sb2S3-MXnsystem
Ling Zan *, Lin Huang, Chengshan Zhang IR Materials Laboratory, Wuhan University, Wuhan 430072, People's Republic of China
Abstract New chalcohalide glasses involving Sb2S 3 and MXn have been prepared. Glass-forming regions have been shown in the Sb2S3-MXn binary systems and Sb2S3-LiF-NaBr, Sb2S3-LiF-CaC12 ternary systems. These glasses are easy to prepare and chemically stable. Depending on the composition, the glass transition temperature, Tg, is between 218 and 230°C, the crystallization temperature, Tc, is between 270 and 330°C and the difference Tc - Tg is between 50 and 90°C, permitting the preparation of preforms of considerable size. These glasses are not transparent in the visible range. The infrared transparent wavelength extends up to about 7.5 txm. These glasses are potential condidates for IR transparent glass around 3-7 I~m. The value of o'(100-200°C) of the glasses is about 10 -5 I'U 1 cm-1.
1. Introduction Chalcohalide glasses containing both halide and chalcogenide components have been studied intensively in recent times [1]. Their glass-forming ability is often better than those of pure halides and chalcogenides. For some properties they are even better than that of pure chalcogenide glasses. Sb2S 3 is considered a glass-former but a pure single-component glass is too difficult to prepare [2]. Tg of the Sb2S 3 glass is 174°C and Tc of the Sb2S 3 glass is also 174°C [3]. It was expected that, by adding the halide as a modifier, the glass-forming ability of the Sb 2 S 3 would have been improved. In this paper, new chalcohalide glasses involving Sb2S 3 and MXn are reported. Glass-forming regions
* Corresponding author. Tel: + 86-27 781 0167. Telefax: + 8627 781 2661.
have been shown. The characteristic temperature, the infrared transmission spectra and the electrical conductivity of the glass samples have been measured.
2. Experimental The starting materials are GR or A R MXn and prepared Sb2S 3. A mixture of Sb2S 3 and MXn was put into a covered quartz crucible in an argon atmosphere and rapidly heated to a temperature between 800 and 850°C [4]. The mixture was completely melted and quenched in air after melting homogeneously for several minutes. Glassy flakes with the thickness of 0 . 5 - 2 m m were found. The glass-forming region of the S b 2 S 3 - M X n system was determind by X-ray diffractometry. The thermal properties of these glasses were measured using a DT-3013 with a heating rate of 10 K s -1. The IR spectra were recorded by a spectraphotometer (Nicolet SX-170).
0022-3093/95/$09.50 © 1995 Elsevier Science B.V. All rights reserved SSDI 0022-3093(94)00593-1
2
L. Zan et al./Journal of Non-Crystalline Solids 184 (1995) 1-4
3. Results +
Binary glasses may be formed by combining S b 2 S 3 and one of the following halides. The results are reported in Tables 1-3. The composition ranges are shown in Fig. 1. Numerous ternary glasses are derived from these binary associations. The results are given in Table 4. Fig. 2 describes the vitreous areas in the Sb2S 3LiF-NaBr and Sb2S3-LiF-CaCI 2 systems. A Typical differential thermal analysis (DTA) curve is shown in Fig. 3. The results are given in Table 5. These glasses are black in color and not transparent in the visible range. Typical transmission curves are
SbzS3
,
'
90
,
Tf
I
I
I
200
400
600
T ('C)
Fig. 3. Typical D A T curve.
T0//°
5
6
40
7
8
10 (urn)
~ .
20
LiF
70 i
4000 Sb~s
' "--"'~" 90
' 70
'
'
'
'
'
' NaCI
3000
2000
1500
Fig. 4. Typical IR transmission curves: - - , . . . . . . , 7 5 S b 2 $3 - 1 5 N a B r - 10LiF.
1000 (cm-L) 7 5 S b 2S 3 - 2 5 N a F ;
Sb~Ss (mot°/~o) Fig. 1. G l a s s - f o r m i n g range in the binary s y s t e m s Sb2S 3 - M X . Table 2 S b 2 S 3 - M X 2 (M = Mg, Ca, Sr, Ba; X = F, CI, Br) system Table 1 S b 2 S 3 - M X (M = Li, Na, K; X = F, CI, Br, I) system
Li Na K
F
CI
Br
I
~ /t
~ ~
tJ u,~
u'~ tl
t,,~, Binary glass m a y be formed as M X concentration ranges f r o m 10 to 25 mol%.
F
C1
Mg
A
Z~
Ca Sr Ba
A A
A
X
A
A
A , Glass with a few crystals; these glasses w o u l d probably require a faster cooling rate than used in these experiments. X , no glass formation.
SbzSa
LiF
Br
Sb2Sa
CaClz-
LiF
Fig. 2. G l a s s - f o r m i n g range in the ternary systems.
NaBr
L. Zan et al. / J o u r n a l of Non-Crystalline Solids 184 (1995) 1 - 4
Table 3 Sb2S3-MX2(3) (M = Zr, Cd, Mn, Co, Ni, La, AI, Gd; X = F, C1, Br) system F
CI
Zn
A
A
Cd Mn Co Ni La AI Gd
A ,',
zx ,', ×
0 × 0
Table 6 Electrical conductivity of glasses System
Composition (mol%)
T(°C)
~ ([l I c m - l )
Sb2S3-NaC1 Sb2S3-NaC1-LiF
80:20 70:15:15 80:20 50:30:20
100-200 100-200 180 180
4 × 10 5 1.5x10 -5 6.8 × |0 7 1.1X 10 8
Br
Sb2S3-T12S [5]
Sb2S3-AszS3 -T12S315]
X
3
×
zx, Glass with a few crystals; these glasses would probably require a faster cooling rate than used in these experiments. 0, not melted ×, no glass formation
the chalcohalide glasses is greater than the multic o m p e n e n t c h a l c o g e n i d e glasses. The conduction m e c h a n i s m requires further study.
4. D i s c u s s i o n
s h o w n in Fig. 4 for a glass sample o f 1 m m thickness. The electrical c o n d u c t i v i t y of these glasses was m e a s u r e d (Table 6). The electrical c o n d u c t i v i t y of
Table 4 Ternary chalcohalide glasses based on Sb2S 3 Binary system
Third component
Binary system
Third component
SzS3-LiF
NaFtl NaClt,,~ NaBru," NaltJ KFt~ KBrt~ KI~ CaCI2 t J ZnCI2 zx
SbzS3-NaF
KFI,,," KCI.o," KBru,'r KIu~ KCltl KBrt~ KIt,J MnF2 A ZnF2 z~ BaCI2 u~'
SbzS3-NaCI
SbzS3-NaF
J,', Ternary glasses may be formed as Sb2S 3 concentration ranges from 90 to 75 mol%.
F r o m Tables 1 - 3 and Figs. 1 and 2, w e can see that the ternary or binary chalcohalide glasses m a y be f o r m e d in c o m b i n i n g Sb2S 3 and alkali halides. Glasses with a f e w crystals m a y be f o r m e d in c o m bining Sb2S 3 and alkaline-earth halides. It is v e r y difficult to form glasses by c o m b i n i n g Sb2S 3 and other metal halides. T a b l e 5 s h o w s that the values of Tg and Tc of the n e w chalcohalide glasses are higher than that o f Sb2S 3 glass; the value of Tc is influenced by the halide c o m p o s i t i o n ; the v a l u e of Tg is influenced by the halide content. W h e n the halide content increases, the v a l u e o f Tg increases. F r o m Table 5, we can see that by adding the halide the g l a s s - f o r m i n g ability o f Sb2S 3 has been greatly i m p r o v e d , Tc - Tg can reach 90°C, permitting the preparation o f pref o r m s of considerable size. The absorption band at 2.9 Ixm results from traces of h y d r o x y l groups and water in Fig. 4. The band
Table 5 The characteristic temperatures of the glasses System
Composition (mol%)
Tg (°C)
Tc (°C)
"If (°C)
Tc - Tg (°C)
Sb2S3-LiF Sb2S3-NaC1 Sb2S3-NaBr Sb2S3-Nal Sb2S3-LiF-NaCI Sb2S314]
80:20 80:20 90:10 90:10 70:15:15 100
228 225 218 218 230 174
330 310 273 270 300 300 174
470 405 469 430 405 460 394 470
92 85 55 53 70
4
L. Zan et al./Journal of Non-Crystalline Solids 184 (1995) 1-4
can be eliminated if care is taken during preparation and processing. The transmission of prepared glasses is low; the starting materials require further purification.
wavelength extends up to about 7.5 ~ m . These glasses are potential candidates for IR-transparent glasses ~ 3 - 7 ~ m .
References 5. Conclusion In this work, Sb2S 3 and MXn ming areas have tion temperature T ~ - T g between
new chalcohalide glasses involving have been prepared. The glass-forbeen investigated. The glass transilies between 218 and 230°C and 50 and 90°C. The IR-transparent
[1] J. Pottier, J. Non-Cryst. Solids 112 (1989) 2325. [2] Z. Ling, MS thesis, Wuhan University (1987). [3] L. Cervinka and A. Hrudy, J. Non-Cryst Solids 48 (1982) 231. [4] J.L. Mutz, M. Poulain and F. Chiquet, presented at 8th Int. Symp. on Halide Glasses, Perros Guirec, Franee, Sept. 1992. [5] J. Olivier-Fourcade, A. Bouaza and J.C. Jumas, J. Non-Cryst. Solids 111 (1989) 277.
ELSEVIER
Journal of Non-Crystalline Solids 184 (1995) 1-4
New chalcohalide glasses from the
Sb2S3-MXnsystem
Ling Zan *, Lin Huang, Chengshan Zhang IR Materials Laboratory, Wuhan University, Wuhan 430072, People's Republic of China
Abstract New chalcohalide glasses involving Sb2S 3 and MXn have been prepared. Glass-forming regions have been shown in the Sb2S3-MXn binary systems and Sb2S3-LiF-NaBr, Sb2S3-LiF-CaC12 ternary systems. These glasses are easy to prepare and chemically stable. Depending on the composition, the glass transition temperature, Tg, is between 218 and 230°C, the crystallization temperature, Tc, is between 270 and 330°C and the difference Tc - Tg is between 50 and 90°C, permitting the preparation of preforms of considerable size. These glasses are not transparent in the visible range. The infrared transparent wavelength extends up to about 7.5 txm. These glasses are potential condidates for IR transparent glass around 3-7 I~m. The value of o'(100-200°C) of the glasses is about 10 -5 I'U 1 cm-1.
1. Introduction Chalcohalide glasses containing both halide and chalcogenide components have been studied intensively in recent times [1]. Their glass-forming ability is often better than those of pure halides and chalcogenides. For some properties they are even better than that of pure chalcogenide glasses. Sb2S 3 is considered a glass-former but a pure single-component glass is too difficult to prepare [2]. Tg of the Sb2S 3 glass is 174°C and Tc of the Sb2S 3 glass is also 174°C [3]. It was expected that, by adding the halide as a modifier, the glass-forming ability of the Sb 2 S 3 would have been improved. In this paper, new chalcohalide glasses involving Sb2S 3 and MXn are reported. Glass-forming regions
* Corresponding author. Tel: + 86-27 781 0167. Telefax: + 8627 781 2661.
have been shown. The characteristic temperature, the infrared transmission spectra and the electrical conductivity of the glass samples have been measured.
2. Experimental The starting materials are GR or A R MXn and prepared Sb2S 3. A mixture of Sb2S 3 and MXn was put into a covered quartz crucible in an argon atmosphere and rapidly heated to a temperature between 800 and 850°C [4]. The mixture was completely melted and quenched in air after melting homogeneously for several minutes. Glassy flakes with the thickness of 0 . 5 - 2 m m were found. The glass-forming region of the S b 2 S 3 - M X n system was determind by X-ray diffractometry. The thermal properties of these glasses were measured using a DT-3013 with a heating rate of 10 K s -1. The IR spectra were recorded by a spectraphotometer (Nicolet SX-170).
0022-3093/95/$09.50 © 1995 Elsevier Science B.V. All rights reserved SSDI 0022-3093(94)00593-1
2
L. Zan et al./Journal of Non-Crystalline Solids 184 (1995) 1-4
3. Results +
Binary glasses may be formed by combining S b 2 S 3 and one of the following halides. The results are reported in Tables 1-3. The composition ranges are shown in Fig. 1. Numerous ternary glasses are derived from these binary associations. The results are given in Table 4. Fig. 2 describes the vitreous areas in the Sb2S 3LiF-NaBr and Sb2S3-LiF-CaCI 2 systems. A Typical differential thermal analysis (DTA) curve is shown in Fig. 3. The results are given in Table 5. These glasses are black in color and not transparent in the visible range. Typical transmission curves are
SbzS3
,
'
90
,
Tf
I
I
I
200
400
600
T ('C)
Fig. 3. Typical D A T curve.
T0//°
5
6
40
7
8
10 (urn)
~ .
20
LiF
70 i
4000 Sb~s
' "--"'~" 90
' 70
'
'
'
'
'
' NaCI
3000
2000
1500
Fig. 4. Typical IR transmission curves: - - , . . . . . . , 7 5 S b 2 $3 - 1 5 N a B r - 10LiF.
1000 (cm-L) 7 5 S b 2S 3 - 2 5 N a F ;
Sb~Ss (mot°/~o) Fig. 1. G l a s s - f o r m i n g range in the binary s y s t e m s Sb2S 3 - M X . Table 2 S b 2 S 3 - M X 2 (M = Mg, Ca, Sr, Ba; X = F, CI, Br) system Table 1 S b 2 S 3 - M X (M = Li, Na, K; X = F, CI, Br, I) system
Li Na K
F
CI
Br
I
~ /t
~ ~
tJ u,~
u'~ tl
t,,~, Binary glass m a y be formed as M X concentration ranges f r o m 10 to 25 mol%.
F
C1
Mg
A
Z~
Ca Sr Ba
A A
A
X
A
A
A , Glass with a few crystals; these glasses w o u l d probably require a faster cooling rate than used in these experiments. X , no glass formation.
SbzSa
LiF
Br
Sb2Sa
CaClz-
LiF
Fig. 2. G l a s s - f o r m i n g range in the ternary systems.
NaBr
L. Zan et al. / J o u r n a l of Non-Crystalline Solids 184 (1995) 1 - 4
Table 3 Sb2S3-MX2(3) (M = Zr, Cd, Mn, Co, Ni, La, AI, Gd; X = F, C1, Br) system F
CI
Zn
A
A
Cd Mn Co Ni La AI Gd
A ,',
zx ,', ×
0 × 0
Table 6 Electrical conductivity of glasses System
Composition (mol%)
T(°C)
~ ([l I c m - l )
Sb2S3-NaC1 Sb2S3-NaC1-LiF
80:20 70:15:15 80:20 50:30:20
100-200 100-200 180 180
4 × 10 5 1.5x10 -5 6.8 × |0 7 1.1X 10 8
Br
Sb2S3-T12S [5]
Sb2S3-AszS3 -T12S315]
X
3
×
zx, Glass with a few crystals; these glasses would probably require a faster cooling rate than used in these experiments. 0, not melted ×, no glass formation
the chalcohalide glasses is greater than the multic o m p e n e n t c h a l c o g e n i d e glasses. The conduction m e c h a n i s m requires further study.
4. D i s c u s s i o n
s h o w n in Fig. 4 for a glass sample o f 1 m m thickness. The electrical c o n d u c t i v i t y of these glasses was m e a s u r e d (Table 6). The electrical c o n d u c t i v i t y of
Table 4 Ternary chalcohalide glasses based on Sb2S 3 Binary system
Third component
Binary system
Third component
SzS3-LiF
NaFtl NaClt,,~ NaBru," NaltJ KFt~ KBrt~ KI~ CaCI2 t J ZnCI2 zx
SbzS3-NaF
KFI,,," KCI.o," KBru,'r KIu~ KCltl KBrt~ KIt,J MnF2 A ZnF2 z~ BaCI2 u~'
SbzS3-NaCI
SbzS3-NaF
J,', Ternary glasses may be formed as Sb2S 3 concentration ranges from 90 to 75 mol%.
F r o m Tables 1 - 3 and Figs. 1 and 2, w e can see that the ternary or binary chalcohalide glasses m a y be f o r m e d in c o m b i n i n g Sb2S 3 and alkali halides. Glasses with a f e w crystals m a y be f o r m e d in c o m bining Sb2S 3 and alkaline-earth halides. It is v e r y difficult to form glasses by c o m b i n i n g Sb2S 3 and other metal halides. T a b l e 5 s h o w s that the values of Tg and Tc of the n e w chalcohalide glasses are higher than that o f Sb2S 3 glass; the value of Tc is influenced by the halide c o m p o s i t i o n ; the v a l u e of Tg is influenced by the halide content. W h e n the halide content increases, the v a l u e o f Tg increases. F r o m Table 5, we can see that by adding the halide the g l a s s - f o r m i n g ability o f Sb2S 3 has been greatly i m p r o v e d , Tc - Tg can reach 90°C, permitting the preparation o f pref o r m s of considerable size. The absorption band at 2.9 Ixm results from traces of h y d r o x y l groups and water in Fig. 4. The band
Table 5 The characteristic temperatures of the glasses System
Composition (mol%)
Tg (°C)
Tc (°C)
"If (°C)
Tc - Tg (°C)
Sb2S3-LiF Sb2S3-NaC1 Sb2S3-NaBr Sb2S3-Nal Sb2S3-LiF-NaCI Sb2S314]
80:20 80:20 90:10 90:10 70:15:15 100
228 225 218 218 230 174
330 310 273 270 300 300 174
470 405 469 430 405 460 394 470
92 85 55 53 70
4
L. Zan et al./Journal of Non-Crystalline Solids 184 (1995) 1-4
can be eliminated if care is taken during preparation and processing. The transmission of prepared glasses is low; the starting materials require further purification.
wavelength extends up to about 7.5 ~ m . These glasses are potential candidates for IR-transparent glasses ~ 3 - 7 ~ m .
References 5. Conclusion In this work, Sb2S 3 and MXn ming areas have tion temperature T ~ - T g between
new chalcohalide glasses involving have been prepared. The glass-forbeen investigated. The glass transilies between 218 and 230°C and 50 and 90°C. The IR-transparent
[1] J. Pottier, J. Non-Cryst. Solids 112 (1989) 2325. [2] Z. Ling, MS thesis, Wuhan University (1987). [3] L. Cervinka and A. Hrudy, J. Non-Cryst Solids 48 (1982) 231. [4] J.L. Mutz, M. Poulain and F. Chiquet, presented at 8th Int. Symp. on Halide Glasses, Perros Guirec, Franee, Sept. 1992. [5] J. Olivier-Fourcade, A. Bouaza and J.C. Jumas, J. Non-Cryst. Solids 111 (1989) 277.