- Email: [email protected]
UV-laser irradiation on the soda-lime silicate glass
international journal of hydrogen energy 34 (2009) 1123–1125
Available at www.sciencedirect.com
journal homepage: www.elsevier.com/locate/he
Technical Communication
UV-laser irradiation on the soda-lime silicate glass Jiawei Shenga, Yanfen Wua, Xinji Yangb, Jian Zhanga,* a
College of Chemical Engineering and Materials Science, Zhejiang University of Technology, Zhaohui No. 6, Hangzhou, Zhejiang 310032, China b College of medicine, Jiaxing University, Zhejiang 314001, China
article info
abstract
Article history:
Defects induced by ArF UV-laser irradiation in the soda-lime silicate glass were studied by
Received 29 October 2008
means of optical spectrophotometric and electron spin resonance measurements. The UV-
Accepted 31 October 2008
laser induced defects in glass showed similar behavior to the X-ray induced defects. The
Available online 13 December 2008
defects of nonbridging oxygen hole centers attributed to two absorption peaks at 431 and 627 nm which were observed in the glass after the UV-laser radiation. The induced
Keywords:
absorption increased when laser irradiation time or energy density increased. Our results
ArF UV-laser
demonstrated that the induced color in glass by UV-laser radiation could be bleached
Glass
reversibly, which provides an alternative way to develop a recyclable colored glass.
Defects
ª 2008 International Association for Hydrogen Energy. Published by Elsevier Ltd. All rights
Optical absorption
1.
Introduction
The study of high-energy ionizing radiation on glass has been carried out for many decades. The mechanism and nature of the radiation damage on defects of silicate glasses have been critically reviewed by many authors [1–3]. The recent advent of new glass compositions for optical fiber waveguides that may be exposed to radiation has triggered studies of the radiation-induced changes in the optical transmission of glasses. By characterizing the resultant defects that occur when glass is irradiated, it has been often possible to determine, or at least postulate, the preexisting flaws in the glass structure that cause the defects, and how modifier ions or dopants are incorporated into the glass matrix and participate in the damaging process [2]. However, much work has been referred to high-energy radiation such as that produced by nuclear reactors, particle accelerators, and X-ray machine.
reserved.
Currently, most of the used colored glasses are difficult to recycle and treated as waste. Development of recyclable colored glasses is of great interest from the view point of economics and environment. The application of the highenergy radiation for inducing colors in soda-lime glass has recently prompted a renewed interest since the induced color can be bleached reversibly. Sheng et al. have investigated the X-ray irradiation-induced defects of the glass that were found to attribute to the optical absorptions [4]. The induced color was unstable at room temperature and decolorized after thermal annealing. However, little work has been carried on the defects of the glass using other radiation techniques such as low energy UV irradiation. In the present study, we used an ArF UV-laser to induce defects in soda-lime silicate and characterized the defects by optical spectrophotometric and electron spin resonance (ESR) measurements. Our results could not only provide some basic data of laser irradiation-induced
* Corresponding author. Tel.: þ86 571 88320851. E-mail address: [email protected] (J. Zhang). 0360-3199/$ – see front matter ª 2008 International Association for Hydrogen Energy. Published by Elsevier Ltd. All rights reserved. doi:10.1016/j.ijhydene.2008.10.097
1124
international journal of hydrogen energy 34 (2009) 1123–1125
properties of glass, but also present an alternative way to produce a recyclable colored glass.
1500
Experimental
Commercial soda-lime silicate glass substrates composed of (wt%): 73.2 SiO2, 15.3 Na2O, 1.3 Al2O3, and 10.2 CaO were used. Analytically pure carbonates and oxides of the elements mentioned were melted in a platinum crucible at 1400 C for 3 h under an air atmosphere followed by annealing at 550 C for 1 h. The glass was ground and polished and cut into 10 20 2 mm3 plates. Irradiation was performed using an ArF (l ¼ 193 nm) excimer laser. The laser beam is shaped by lenses and an aperture until a cross section of 5 5 mm2 was obtained. Irradiation was carried out at an output energy density of 25–400 mJ/cm2/pulse, with a repetition frequency of 10 Hz and 20 ns pulse duration. With these parameter settings, the laser irradiation time ranged from 10 s to 200 min. Optical absorption spectra were recorded using a SHIMADZU UV-2550 spectrophotometer at ambient room temperature and all recorded optical spectra were referred to air. First-derivative ESR measurements were conducted at room temperature on a BRUKER 300E, operating at 9.7 GHz. The g-value in ESR spectra was defined by the equation of hv ¼ gbH, where h is the Planck’s constant, v the spectrometer frequency, b the Bohr magneton, and H is the magnitude of the laboratory applied magnetic field at resonance.
Results and discussion
As shown in Fig. 1, the as-quenched base glass was colorless and had no measurable absorptions in the visible region. In addition, no ESR signal was observed in the blank samples. After laser irradiation, two characteristic absorption bands in the visible region with maxima at about 620, and 430 nm,
2.0
Absorption, cm-1
50 h after irradiation
1.5
Absorption, cm-1
As irradiated
0 E' center g=1.992
-500
-1500 3300
3350
3400
3450
3500
3550
3600
Magnetic induction, Gauss Fig. 2 – ESR spectra of glass after irradiation at 75 mJ/cm2 for 10 min.
respectively, were observed. More precise peak positions were determined to be 627 and 431 nm for these two bands, respectively, with the assistance of Gaussian resolution [2,5,6] (Fig. 1, insert). As a result, the glass showed slight brown. The induced color was unstable, as indicated by the decease of the peak intensity after 50 h room temperature storage following the irradiation (Fig. 1). These results were similar to the case using X-ray radiation [4]. Radiation may cause the displacement of lattice atoms or electron defects that involve changes in the valence state of lattice or impurity atoms. The ionizing radiation produces electron-hole pairs in the glass structure. Accordingly, new optical absorption bands were developed [1–4]. In general, these absorptions are associated with either oxygen deficiency or oxygen excess in the glass network. The most fundamental radiation-induced defects in glass are the non0 bridging oxygen hole center (NBOHC: ^Si–O*), the E center (^Si*), the peroxy radical (POR: ^Si–O–O*), and the trapped
3.0
2.0
Base glass
500
pre-irradiated 10 s 1 min 10 min 30 min 60 min 200 min
1.5
2.5 1.0 431 nm 0.5
627 nm
0.0 300 400 500 600 700 800 900
1.0
Wavelength. nm
2.0
1.6
Absorption, cm-1
3.
NBOHCs g=1.99~2.00
-1000
Absorption, cm-1
2.
ESR intensity, a.u.
1000
1.5
627 nm 431 nm
1.4 1.2 1.0 0.8 0.6 10
100
1000
10000
Irradiation time, s
1.0
0.5
0.5
0.0
300
400
500
600
700
800
900
Wavelength, nm Fig. 1 – Optical absorptions in soda-lime silicate glass after UV-laser irradiation at 75 mJ/cm2 for 10 min (insert: Gaussian resolution of induced absorptions).
0.0
300
400
500
600
700
800
900
Wavelength, nm Fig. 3 – Radiation induced optical absorption with varied irradiation time (75 mJ/cm2) (insert: Optical absorptions affected by irradiation time).
international journal of hydrogen energy 34 (2009) 1123–1125
energy density was increased, while the induced absorption peak positions were relatively constant.
3.0 1.2 2
Absorption, cm-1
Absorption, cm-1
25 mJ/cm 70 mJ/cm2 250 mJ/cm2 400 mJ/cm2
2.4
627 nm 431 nm
1.1
1.8
1.0 0.9
4.
0.8 0.7
0.4 0
50 100 150 200 250 300 350 400
Energy, mJ/cm2
1.2
0.6
0.0 400
500
Conclusions
0.6 0.5
300
1125
600
700
800
900
Wavelength, nm Fig. 4 – Optical absorptions affected by irradiation energy (100 shots) (insert: Optical absorptions affected by irradiation energy).
electrons (TE), where the notation ‘‘^’’ represents three bonds with other oxygen in the glass network and ‘‘*’’ denotes an unpaired electron. According to current knowledge, absorption bands of 627 and 431 nm in the soda-lime silicate glass were identified mainly as absorption of NBOHCs [5–8]. The 0 main absorptions of the E center and the POR are in the far UV region, which have less effect on the glass visible color. Fig. 2 shows the ESR spectrum of the glass after the irradiation. Two distinctive signals at g ¼ 1.99 w 2.00 and g ¼ 1.992, respectively, were observed. As expected, the g ¼ 1.99 w 2.00 was identified as the defects of NBOHCs, correlating absorption bands of 627 and 431 nm. The signal of g ¼ 1.992 might attri0 bute to the defect of E center. The spectra of the induced absorption with varying exposure time are presented in Fig. 3. The peak heights of the induced absorption increased with the laser irradiation time, and the peak positions absorption band were relatively constant, suggesting that only variations of their populations of defects be effected by the irradiation time. As shown in Fig. 3 (insert), the absorptions at 627 or 431 nm increased rapidly during the first 30 min radiation. The increase was then slow down and no more increase was observed after 60 min radiation. Irradiation energy is another important factor that affects the induced absorption of glass. As can be seen in Fig. 4, the induced absorption increased when the
In summary, this study investigated the ArF UV-laser irradiation on the soda-lime silicate glass. The UV-laser induced defects in glass showed similar behavior to the X-ray induced defects. The induced optical absorption was due to the generation of defects by the laser irradiation. Two absorption bands at 627 and 431 nm were observed, presumably due to the induced NBOHCs. The absorption bands increased when the laser irradiation time or energy density of the laser increased. Our results demonstrated that the induced color in glass by UV radiation could be bleached reversibly, which provides an alternative way to develop a recyclable colored glass.
Acknowledgement The authors gratefully acknowledge the financial support for this work from Zhejiang Provincial Natural Science Foundation of China (Y406033, Y4080034).
references
[1] Rajaram M, Friebele EJ. Effects of radiation on the properties of low thermal expansion coefficient materials: a review. J NonCryst Solids 1989;108:1–17. [2] Friebele EJ. Radiation effects in optical and properties of glass. New York, Westerville; 1991. [3] Marshall CD, Speth JA, Payne SA. Induced optical absorption in gamma, neutron and ultraviolet irradiated fused quartz and silica. J Non-Cryst Solids 1997;212:59–73. [4] Sheng J. Photo-induced and controlled synthesis of Ag nanocluster in soda-lime silicate glass. Int J Hydrogen Energy 2007;32(13). 2062–65. [5] Bishay A. Radiation induced color centers in multicomponent glasses. J Non-Cryst Solids 1970;3:54–114. [6] Zhang J, Dong W, Qiao L, Li J, Zheng J, Sheng J. Silver nanocluster formation in the soda-lime glass by X-ray irradiation and annealing. J Cryst Growth 2007;305:278–84. [7] Wong J, Angell CA. Glass: structure by spectroscopy. New York: Marcel Dekker; 1976. [8] Sheng J, Li J, Yu J. The development of silver nanoclusters in ion-exchanged soda-lime silicate glasses. Int J Hydrogen Energy 2007;32(13):2598–601.
Available at www.sciencedirect.com
journal homepage: www.elsevier.com/locate/he
Technical Communication
UV-laser irradiation on the soda-lime silicate glass Jiawei Shenga, Yanfen Wua, Xinji Yangb, Jian Zhanga,* a
College of Chemical Engineering and Materials Science, Zhejiang University of Technology, Zhaohui No. 6, Hangzhou, Zhejiang 310032, China b College of medicine, Jiaxing University, Zhejiang 314001, China
article info
abstract
Article history:
Defects induced by ArF UV-laser irradiation in the soda-lime silicate glass were studied by
Received 29 October 2008
means of optical spectrophotometric and electron spin resonance measurements. The UV-
Accepted 31 October 2008
laser induced defects in glass showed similar behavior to the X-ray induced defects. The
Available online 13 December 2008
defects of nonbridging oxygen hole centers attributed to two absorption peaks at 431 and 627 nm which were observed in the glass after the UV-laser radiation. The induced
Keywords:
absorption increased when laser irradiation time or energy density increased. Our results
ArF UV-laser
demonstrated that the induced color in glass by UV-laser radiation could be bleached
Glass
reversibly, which provides an alternative way to develop a recyclable colored glass.
Defects
ª 2008 International Association for Hydrogen Energy. Published by Elsevier Ltd. All rights
Optical absorption
1.
Introduction
The study of high-energy ionizing radiation on glass has been carried out for many decades. The mechanism and nature of the radiation damage on defects of silicate glasses have been critically reviewed by many authors [1–3]. The recent advent of new glass compositions for optical fiber waveguides that may be exposed to radiation has triggered studies of the radiation-induced changes in the optical transmission of glasses. By characterizing the resultant defects that occur when glass is irradiated, it has been often possible to determine, or at least postulate, the preexisting flaws in the glass structure that cause the defects, and how modifier ions or dopants are incorporated into the glass matrix and participate in the damaging process [2]. However, much work has been referred to high-energy radiation such as that produced by nuclear reactors, particle accelerators, and X-ray machine.
reserved.
Currently, most of the used colored glasses are difficult to recycle and treated as waste. Development of recyclable colored glasses is of great interest from the view point of economics and environment. The application of the highenergy radiation for inducing colors in soda-lime glass has recently prompted a renewed interest since the induced color can be bleached reversibly. Sheng et al. have investigated the X-ray irradiation-induced defects of the glass that were found to attribute to the optical absorptions [4]. The induced color was unstable at room temperature and decolorized after thermal annealing. However, little work has been carried on the defects of the glass using other radiation techniques such as low energy UV irradiation. In the present study, we used an ArF UV-laser to induce defects in soda-lime silicate and characterized the defects by optical spectrophotometric and electron spin resonance (ESR) measurements. Our results could not only provide some basic data of laser irradiation-induced
* Corresponding author. Tel.: þ86 571 88320851. E-mail address: [email protected] (J. Zhang). 0360-3199/$ – see front matter ª 2008 International Association for Hydrogen Energy. Published by Elsevier Ltd. All rights reserved. doi:10.1016/j.ijhydene.2008.10.097
1124
international journal of hydrogen energy 34 (2009) 1123–1125
properties of glass, but also present an alternative way to produce a recyclable colored glass.
1500
Experimental
Commercial soda-lime silicate glass substrates composed of (wt%): 73.2 SiO2, 15.3 Na2O, 1.3 Al2O3, and 10.2 CaO were used. Analytically pure carbonates and oxides of the elements mentioned were melted in a platinum crucible at 1400 C for 3 h under an air atmosphere followed by annealing at 550 C for 1 h. The glass was ground and polished and cut into 10 20 2 mm3 plates. Irradiation was performed using an ArF (l ¼ 193 nm) excimer laser. The laser beam is shaped by lenses and an aperture until a cross section of 5 5 mm2 was obtained. Irradiation was carried out at an output energy density of 25–400 mJ/cm2/pulse, with a repetition frequency of 10 Hz and 20 ns pulse duration. With these parameter settings, the laser irradiation time ranged from 10 s to 200 min. Optical absorption spectra were recorded using a SHIMADZU UV-2550 spectrophotometer at ambient room temperature and all recorded optical spectra were referred to air. First-derivative ESR measurements were conducted at room temperature on a BRUKER 300E, operating at 9.7 GHz. The g-value in ESR spectra was defined by the equation of hv ¼ gbH, where h is the Planck’s constant, v the spectrometer frequency, b the Bohr magneton, and H is the magnitude of the laboratory applied magnetic field at resonance.
Results and discussion
As shown in Fig. 1, the as-quenched base glass was colorless and had no measurable absorptions in the visible region. In addition, no ESR signal was observed in the blank samples. After laser irradiation, two characteristic absorption bands in the visible region with maxima at about 620, and 430 nm,
2.0
Absorption, cm-1
50 h after irradiation
1.5
Absorption, cm-1
As irradiated
0 E' center g=1.992
-500
-1500 3300
3350
3400
3450
3500
3550
3600
Magnetic induction, Gauss Fig. 2 – ESR spectra of glass after irradiation at 75 mJ/cm2 for 10 min.
respectively, were observed. More precise peak positions were determined to be 627 and 431 nm for these two bands, respectively, with the assistance of Gaussian resolution [2,5,6] (Fig. 1, insert). As a result, the glass showed slight brown. The induced color was unstable, as indicated by the decease of the peak intensity after 50 h room temperature storage following the irradiation (Fig. 1). These results were similar to the case using X-ray radiation [4]. Radiation may cause the displacement of lattice atoms or electron defects that involve changes in the valence state of lattice or impurity atoms. The ionizing radiation produces electron-hole pairs in the glass structure. Accordingly, new optical absorption bands were developed [1–4]. In general, these absorptions are associated with either oxygen deficiency or oxygen excess in the glass network. The most fundamental radiation-induced defects in glass are the non0 bridging oxygen hole center (NBOHC: ^Si–O*), the E center (^Si*), the peroxy radical (POR: ^Si–O–O*), and the trapped
3.0
2.0
Base glass
500
pre-irradiated 10 s 1 min 10 min 30 min 60 min 200 min
1.5
2.5 1.0 431 nm 0.5
627 nm
0.0 300 400 500 600 700 800 900
1.0
Wavelength. nm
2.0
1.6
Absorption, cm-1
3.
NBOHCs g=1.99~2.00
-1000
Absorption, cm-1
2.
ESR intensity, a.u.
1000
1.5
627 nm 431 nm
1.4 1.2 1.0 0.8 0.6 10
100
1000
10000
Irradiation time, s
1.0
0.5
0.5
0.0
300
400
500
600
700
800
900
Wavelength, nm Fig. 1 – Optical absorptions in soda-lime silicate glass after UV-laser irradiation at 75 mJ/cm2 for 10 min (insert: Gaussian resolution of induced absorptions).
0.0
300
400
500
600
700
800
900
Wavelength, nm Fig. 3 – Radiation induced optical absorption with varied irradiation time (75 mJ/cm2) (insert: Optical absorptions affected by irradiation time).
international journal of hydrogen energy 34 (2009) 1123–1125
energy density was increased, while the induced absorption peak positions were relatively constant.
3.0 1.2 2
Absorption, cm-1
Absorption, cm-1
25 mJ/cm 70 mJ/cm2 250 mJ/cm2 400 mJ/cm2
2.4
627 nm 431 nm
1.1
1.8
1.0 0.9
4.
0.8 0.7
0.4 0
50 100 150 200 250 300 350 400
Energy, mJ/cm2
1.2
0.6
0.0 400
500
Conclusions
0.6 0.5
300
1125
600
700
800
900
Wavelength, nm Fig. 4 – Optical absorptions affected by irradiation energy (100 shots) (insert: Optical absorptions affected by irradiation energy).
electrons (TE), where the notation ‘‘^’’ represents three bonds with other oxygen in the glass network and ‘‘*’’ denotes an unpaired electron. According to current knowledge, absorption bands of 627 and 431 nm in the soda-lime silicate glass were identified mainly as absorption of NBOHCs [5–8]. The 0 main absorptions of the E center and the POR are in the far UV region, which have less effect on the glass visible color. Fig. 2 shows the ESR spectrum of the glass after the irradiation. Two distinctive signals at g ¼ 1.99 w 2.00 and g ¼ 1.992, respectively, were observed. As expected, the g ¼ 1.99 w 2.00 was identified as the defects of NBOHCs, correlating absorption bands of 627 and 431 nm. The signal of g ¼ 1.992 might attri0 bute to the defect of E center. The spectra of the induced absorption with varying exposure time are presented in Fig. 3. The peak heights of the induced absorption increased with the laser irradiation time, and the peak positions absorption band were relatively constant, suggesting that only variations of their populations of defects be effected by the irradiation time. As shown in Fig. 3 (insert), the absorptions at 627 or 431 nm increased rapidly during the first 30 min radiation. The increase was then slow down and no more increase was observed after 60 min radiation. Irradiation energy is another important factor that affects the induced absorption of glass. As can be seen in Fig. 4, the induced absorption increased when the
In summary, this study investigated the ArF UV-laser irradiation on the soda-lime silicate glass. The UV-laser induced defects in glass showed similar behavior to the X-ray induced defects. The induced optical absorption was due to the generation of defects by the laser irradiation. Two absorption bands at 627 and 431 nm were observed, presumably due to the induced NBOHCs. The absorption bands increased when the laser irradiation time or energy density of the laser increased. Our results demonstrated that the induced color in glass by UV radiation could be bleached reversibly, which provides an alternative way to develop a recyclable colored glass.
Acknowledgement The authors gratefully acknowledge the financial support for this work from Zhejiang Provincial Natural Science Foundation of China (Y406033, Y4080034).
references
[1] Rajaram M, Friebele EJ. Effects of radiation on the properties of low thermal expansion coefficient materials: a review. J NonCryst Solids 1989;108:1–17. [2] Friebele EJ. Radiation effects in optical and properties of glass. New York, Westerville; 1991. [3] Marshall CD, Speth JA, Payne SA. Induced optical absorption in gamma, neutron and ultraviolet irradiated fused quartz and silica. J Non-Cryst Solids 1997;212:59–73. [4] Sheng J. Photo-induced and controlled synthesis of Ag nanocluster in soda-lime silicate glass. Int J Hydrogen Energy 2007;32(13). 2062–65. [5] Bishay A. Radiation induced color centers in multicomponent glasses. J Non-Cryst Solids 1970;3:54–114. [6] Zhang J, Dong W, Qiao L, Li J, Zheng J, Sheng J. Silver nanocluster formation in the soda-lime glass by X-ray irradiation and annealing. J Cryst Growth 2007;305:278–84. [7] Wong J, Angell CA. Glass: structure by spectroscopy. New York: Marcel Dekker; 1976. [8] Sheng J, Li J, Yu J. The development of silver nanoclusters in ion-exchanged soda-lime silicate glasses. Int J Hydrogen Energy 2007;32(13):2598–601.