SnO2 nanoparticles concentration dependent structural and luminescence characteristics of Er+ 3 doped zinc-lead-phosphate glass

NOC-18242; No of Pages 5 Journal of Non-Crystalline Solids xxx (2017) xxx–xxx

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SnO2 nanoparticles concentration dependent structural and luminescence characteristics of Er+ 3 doped zinc-lead-phosphate glass Haydar Aboud a,⁎, Raja J. Amjad b,c a b c

Baghdad College of Economic Sciences University, Iraq Advanced Optical Materials Research Group, Department of Physics, Faculty of Science, Universiti Teknologi, Malaysia Department of Physics, COMSATS Institute of Information Technology, 54000, Lahore, Pakistan

a r t i c l e

i n f o

Article history: Received 23 November 2016 Received in revised form 15 February 2017 Accepted 15 March 2017 Available online xxxx Keywords: Photoluminescence Phosphate glass SnO2 nanoparticles Er+3 ions

a b s t r a c t We report the modifications in the structural and luminescence properties of erbium (Er+3) doped Zinc-LeadPhosphate (ZLP) glasses containing SnO2 nanoparticles (SNPs). Glasses are prepared via melt quenching technique and characterized using high resolution scanning electron microscope (FE-SEM), differential thermal analyzer (DTA), Fourier transform infrared (FTIR), UV–Visible absorption and photoluminescence (PL) spectroscopy. The DTA results showed an enhancement in the thermal stability with the incorporation of SNPs. The FESEM micrograph revealed the occurrence of uniformly distributed SNPs with average diameter around 21 nm. FTIR spectra exhibited various bonding vibrations, where the IR transmission band intensities are increased accompanied by a shift with the increase of SNPs contents. The UV–Vis spectra displayed six significant absorption peaks centered around 1536, 979, 799, 650, 523, and 485 nm. Room temperature PL spectra showed three emission peaks centered at 502, 545 and 606 nm. The emission intensities are enhanced with increasing SNPs contents. Present glass composition may be useful for the development of solid state lasers and other photonic devices. © 2017 Elsevier B.V. All rights reserved.

1. Introduction In recent times, the trivalent rare earth ions (REIs) doped inorganic binary and ternary glass system received focused attention due to their distinct physical, structural, thermal, and optical properties useful for efficient photonic device fabrication [1–3]. Glass properties such as transparency, chemical durability, optical gain, inexpensiveness, total recyclability, and the abundance of raw materials are attractive for the development of new materials and assorted technological applications [4–11]. Among all the binary glasses phosphate is considered as a potential host material [12–15] because of several advantages such as good optical properties, low melting temperature, improved chemical stability and good mechanical properties [16–18]. Moreover, phosphate based glass system exhibits prominent luminescent properties when doped with suitable sensitizers, modifiers, and REIs as activators. In the past, many efforts are dedicated for the production and applications of such glasses targeted toward fluorescent lamp, LED, solid state lasers, nuclear waste disposal, display, optical fiber etc. [19–23]. During last few decades, REIs doped glasses have been a subject of interest in optical and electrical applications. Unlike other luminescence ⁎ Corresponding author. E-mail addresses: [email protected] (H. Aboud), [email protected] (R.J. Amjad).

center in glass, sharp emission bands occur due to the inclusion of REIs as activators [24–27]. It is well known that in REIs, the electronic transition that occurs among shielded 4f electrons is responsible for various absorptions and emissions. Interestingly, both absorption and emission bands of REIs inside the glass host are relatively sharp and insignificantly influenced by their surroundings. One does not expect to find large shifts in the emission bands of glasses with widely varying composition [28–30]. Recently, the various metallic nanoparticles (NPs) incorporated glasses with rare earth doping are increasingly studied owing their strong luminescence and high-brightness useful for sundry optical applications [31–35]. Generally, these NPs acting as sensitizers (donor) can well compensate the weak absorption cross-section of RE transitions. When the NPs are positioned in the proximity of REIs they can transfer the electromagnetic energy strongly to the REIs [36]. The occurrence of strong electric field in the neighborhood of NPs is attributed to their localized surface plasmon resonance (LSPR) mediated processes. Despite much research, the potency of Er+3 doped ZLP glasses with SNPs embedment are not yet explored. Considering the considerable technological benefits of REIs doped phosphate glass systems and the strong LSPR effects of metal NPs we prepare a series of Er+3 doped ZLP glasses with SNPs inclusion. The influence of varying SNPs concentration on the thermal, structural and luminescence properties of such glass systems are determined. Glasses are thoroughly characterized by means of spectroscopic and imaging techniques. Results are analyzed and compared.

http://dx.doi.org/10.1016/j.jnoncrysol.2017.03.018 0022-3093/© 2017 Elsevier B.V. All rights reserved.

Please cite this article as: H. Aboud, R.J. Amjad, SnO2 nanoparticles concentration dependent structural and luminescence characteristics of Er+3 doped zinc-lead-phosphate glass, J. Non-Cryst. Solids (2017), http://dx.doi.org/10.1016/j.jnoncrysol.2017.03.018

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H. Aboud, R.J. AmjadJournal of Non-Crystalline Solids xxx (2017) xxx–xxx

Table 1 Nominal composition (in mol%) of Er+3-doped ZLP glass containing various concentration of SNPs. Glass code

P2O5

ZnO

PbO

Er2O3

SnO2

ZLPE1S0.0 ZLPE1S0.10 ZLPE1S0.25 ZLPE1S0.50

59 58.9 58.75 58.5

20 20 20 20

20 20 20 20

1 1 1 1

0 0.1 0.25 0.5

2. Materials and methods Glass samples with nominal composition of (59-x)P2O5-20ZnO20PbO-1Er2O3-xSnO2, where x = 0, 0.05, 0.1, 0.25, 0.5 mol% (hereafter coded as ZLPE1Sx) are prepared using melt quenching method. Sol-gel method is used to synthesize SnO2 NPs in the diameter range of 22– 31 nm [37]. Table 1 enlists the detail glass compositions and their codes. The required proportions of highly analytical grade raw materials in the powder form are weighed on a sensitive weighing machine. The glass constituents are thoroughly mixed using a milling machine for 30 min. The homogeneous mixture is then placed in a platinum crucible before being melted in an electric furnace (1100 °C) for 30 min. Upon achieving the desired viscosity, the molten fluid is quenched in between two pre-heated brass plates and then cooled down to room temperature. Finally, the samples are cut and polished for further characterizations. Highly transparent and scratch fee samples are obtained. The surface morphology and local chemical composition of the prepared glass samples are examined using FESEM. The structural properties in the wavenumber range of 400–2000 cm− 1 at the scanning resolution of 2 cm−1 are determined using FTIR (PerkinElmer, Spectrum two). A Perkin-Elmer Pyris Diamond TG/DTA 7 Series system is used to analyze the thermal properties of synthesized glass samples. The finely powdered samples of weight 5 to 20 mg are loaded in alumina crucible and heated in the DTA instrument at a rate of 10 °C/min. The structural properties of the corresponding glass were measured by means of FTIR Spectroscopy. The absorption spectra of the glass samples in the wavelength range of 200–2000 nm are recorded using a Shimadzu 3101 UV– Vis-NIR spectrophotometer. The absorbance signal is captured via double monochromatic diffraction grating system and photomultiplier R928 detector with resolution of 0.1 nm. The absorption peak wavelength and their assignments are obtained. The PL emission spectra are measured using a Perkin Elmer LS55 Luminescence Spectrophotometer. A xenon discharge lamp (300 b λ b 1300 nm) is used as excitation source. The luminescence signal is analyzed using a Monk-Gillieson type monochromator equipped with a photodiode detector at a particular excitation wavelength. All the characterizations of samples are carried out at room temperature. 3. Results and discussion Fig. 1 depicts the FESEM images of the erbium doped ZLP glass containing 0.25 mol% of SNPs. The nucleation of SnO2 inside the glass matrix

Fig. 2. DTA curves of all glass samples.

Table 2 Thermal characteristics of all synthesized glass samples. Glass code

Tg (°C) ± 0.01

Tc (°C) ± 0.01

Tm (°C) ± 0.01

Tc − Tg (°C) ± 0.001

HR ± 0.001

ZLPE1S0.0 ZLPE1S0.10 ZLPE1S0.25 ZLPE1S0.50

534 530 528 525

655 652 648 642

854 852 850 848

121 122 120 117

0.60 0.61 0.70 0.56

is clearly evidenced (Fig. 1(a)). Fig. 1(b) illustrates the corresponding SNPs size distribution by using Imagej software, which is found to be Gaussian with average NPs diameter ~21 nm. Fig. 2 displays the SNPs concentration dependent DTA curves of all samples. The observation of a broad endothermic hump is assigned to the glass transition temperature (Tg), the exothermic peak is allocated to the crystallization temperature (Tc), and the other endothermic peak corresponded to the melting temperature (Tm).Table 2 summarizes the SNPs concentration dependent variation in the thermal parameters of all glass samples. Fig. 3 shows the SNPs concentration dependent variations in the characteristic transition temperatures and glass stability. The glass transition temperature is found to reduce from 534 to 525 °C with increasing SNPs contents from 0 to 0.5 mol% (Fig. 3(a)). The value of ΔT = T c − T g (a measure of glass thermal stability) is achieved to be higher than 100 °C (Fig. 3(b)). This clearly indicates a good glass forming ability and superior thermal stability of the present glass composition against crystallization or devetrification [38]. Based on the observed good linear relationship between T c − T g and T c with SNPs concentration it is asserted that this types of glass can easily be formed and have potential for device fabrication [39].

Fig. 1. (a) Cross-sectional FESEM image of the ZLPE1S0.25 sample and (b) SNPs size distribution inside the glass.

Please cite this article as: H. Aboud, R.J. Amjad, SnO2 nanoparticles concentration dependent structural and luminescence characteristics of Er+3 doped zinc-lead-phosphate glass, J. Non-Cryst. Solids (2017), http://dx.doi.org/10.1016/j.jnoncrysol.2017.03.018

H. Aboud, R.J. AmjadJournal of Non-Crystalline Solids xxx (2017) xxx–xxx

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Fig. 3. SNPs size dependent variation in (a) Tg and, (b) Tg, Tm, Tc, Tc − Tg for all glass samples.

Fig. 4. FTIR spectra of all samples.

The glass stability is determined in term of Hruby parameter (HR) expressed as [40]: H¼

T c −T g T m −T c

ð1Þ

Calculated values of SNPs concentration dependent HR are enlisted in Table 2. The appearance of higher HR signifies higher thermal stability and improved glass formation ability of the chosen composition [40]. The FTIR spectra of all glass samples are shown in Fig. 4. The absorption bands position the corresponding band assignments are summarized in Table 3. Irrespective of the SNPs contents, the FTIR spectra of

all glasses can be divided into three main regions. The region between 1400 and 1150 cm−1 corresponds to vibrations of non-bridging (PO2) groups, the region around 1150–1000 cm−1 is the characteristic of terminal P\\O− and PO3 groups, and the region between 900 and 700 cm−1 belongs to the vibrations of bridging (P\\O\\P) groups. The absorption bands around 477–486 cm− 1 is allocated to the Bending unit of PO4 tetrahedra. The symmetric stretching modes of bridging oxygen atoms bonded to a phosphorus atom are assigned in the range of 740–748 cm−1. The asymmetric stretching of bridging oxygen atoms bonded to a phosphorus atom (P\\O\\P groups) are allocated around 893–898 cm−1. The vibrations of terminal/end groups of PO3 are occurred around 1108–1117 cm−1 and the asymmetric stretching mode of the two nonbridging oxygen atoms bonded to phosphorus atoms (the O\\P\\O or (PO2) units in the phosphate tetrahedral) are appeared in the range of 1297–1306 cm− 1. The slight shift of the absorption bands toward higher wavenumber with increasing SNPs contents is attributed to the convolution of the P2O5 vibrational mode. Furthermore, an increase in the IR transmission with increasing concentration of SNPs is ascribed to the modification of glass structural units and network structure. Fig. 5 illustrates the assignments absorption spectra of synthesized glasses in the wavelength range of 400–1700 nm. Table 4 depicts the absorption band assignments, wavelength and energy for different galls samples. The assignments spectra are comprised of six significant absorption bands centered at 1536, 979, 799, 650, 523, and 485 nm, which corresponds to the transition from 4I15/2 ground state to 4I13/2, 4 I11/2, 4I9/2, 4F9/2, 2H11/2 and 4F7/2 excited levels of Er3+ ions, respectively. Fig. 6 shows the up-conversion PL spectra in the range of 400– 700 nm for all the glasses under excitation of 797 nm. Three emission bands are evidenced which are centered at 502, 545 and 606 aroused due to transitions from the excited states to the ground state of Er3+ ion (strong green: 2H11/2 → 4I15/2, weak green: 4S3/2 → 4I15/2 and orange: 4 I9/2 → 4I15/2).The PL intensity revealed an enhancement by a factor of four times with increasing SNPs concentrations from 0.1 to 0.25 mol% and then quenched beyond this value. This behavior may be due to the presence of defects in the host material and subsequent carrier

Table 3 The FTIR band positions and assignments for all synthesized glasses.

Glass ZLPE1S0.0 ZLPE1S0.10 ZLPE1S0.25 ZLPE1S0.50

450–490 cm−1 Bending unit in PO4 tetrahedron

700–900 cm−1 Bridging (P\ \O\ \P) oxygen atoms

700–900 cm−1 Bridging (P\ \O\ \P) oxygen atoms

1000–1150 cm−1 Terminal P\ \O− and PO3 groups

1200–1400 cm−1 Vibrations of non-bridging (PO2) groups

477 481 483 486 Increase of intensity with the shifting toward higher wavenumber

740 742 746 748 Increase of intensity with the shifting toward higher wavenumber

893 895 896 898 Increase of intensity with the shifting toward higher wavenumber

1108 1112 1115 1117 Increase of intensity with the shifting toward higher wavenumber

1297 1301 1304 1306 Increase of intensity with the shifting toward higher wavenumber

Please cite this article as: H. Aboud, R.J. Amjad, SnO2 nanoparticles concentration dependent structural and luminescence characteristics of Er+3 doped zinc-lead-phosphate glass, J. Non-Cryst. Solids (2017), http://dx.doi.org/10.1016/j.jnoncrysol.2017.03.018

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H. Aboud, R.J. AmjadJournal of Non-Crystalline Solids xxx (2017) xxx–xxx

Fig. 5. Absorption spectra of synthesized glasses. Fig. 7. Partial energy level diagram of Er+3 showing various transitions. Table 4 Absorption band assignments, energy, and wavelength for all synthesized glasses. Sample

Absorption band

Wavelength λ (nm)

Energy (cm−1)

ZLPE1S0.0 ZLPE1S0.10 ZLPE1S0.25 ZLPE1S0.50

4

1536 979 799 650 523 485

6511 10,215 12,516 15,385 19,121 20,619

I13/2 I11/2 4 I9/2 4 F9/2 2 H11/2 4 F7/2 4

recombination. The most common defect of the oxygen vacancies act as radiative centers in the host and the energy transfer process between SnO2 nanoparticles and Er+3 ions. Conversely, the observed PL intensity quenching is attributed to the increasing agglomeration of SNPs, decreasing the surface-to-volume ratio, and the energy transfer from Er+3 ion to the surface of SNPs. Fig. 6(b) demonstrates the SNPs concentration dependent PL intensity enhancement factor for different transitions. The occurrence of PL emission is further explained using the partial energy level diagram of Er+3 ions as depicted in Fig. 7. The up-conversion emission mechanism is comprised of excited state absorption (ESA) and energy transfer (ET). The excitation energy converts to upconversion luminescence spectra by sequential absorption of photons from ground state (4I15/2 → 4I9/2). The non-radiative losses and multiphonon relaxations can be observed at (4I9/2 → 4I11/2, 4I11/2 → 4I13/2, 4 I7/2 → 2H11/2 and 2H11/2 → 4S3/2). The probability of energy transfer (ET) between two neighboring Er+ 3 ions is indicated at (4I11/ 4 4 9 4 4 2 → I15/2) non-radiative decay, and ( I13/2 → F9/2), ( I11/2 → I7/2)

transfer the energy to another one. Moreover, the three prominent emission spectra are observed according to the following transitions (green: 2H11/2 → 4I15/2), (green: 4S3/2 → 4I15/2) and (orange: 4I9/ 4 2 → I15/2). 4. Conclusion A series of Er+ 3 ions doped ZLP glasses containing SNPs are prepared via melt quenching method. The influence of SNPs concentration on the structure, thermal and luminescence properties are determined. FESEM images verified the existence of SNPs and DTA data confirmed the thermal stability of the prepared glasses. FTIR demonstrated the modification of bonding vibration due to the inclusion of SNPs. The PL spectra revealed intensity enhancement up to NPs concentration of 0.25 mol% and quenched at higher SNPs contents (0.5 mol%). The energy transfer from the NPs to the REI is majorly attributed to this enhancement. The creation of LSPR mediated strong local electric field of the NPs induced enhanced emission of REI that occurred in the vicinity of NPs. Good features of the results suggest that the present glass system is useful for solid-state laser and other optical devices. Acknowledgments Dr. R.J. Amjad would like to thanks The World Academy of Sciences (TWAS, Italy) for providing financial support under the grant number 15-036 RG/REN/AS_C-FR3240288933.

Fig. 6. (a) Up-conversion PL spectra of prepared glass system, and (b) SNPs concentration dependent variation in the normalized PL intensity.

Please cite this article as: H. Aboud, R.J. Amjad, SnO2 nanoparticles concentration dependent structural and luminescence characteristics of Er+3 doped zinc-lead-phosphate glass, J. Non-Cryst. Solids (2017), http://dx.doi.org/10.1016/j.jnoncrysol.2017.03.018

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References [1] W.H. Zachariasen, J. Am. Chem. Soc. 54 (1932) 38,3841. [2] M. Reza Dousti, M.R. Sahar, S.K. Ghoshal, Raja J. Amjad, A.R. Samavati, J. Mol. Struct. 1035 (2013). [3] M. Nogami, Y. Abe, Appl. Phys. Lett. 69 (1996) 3776. [4] M. Fuju, M. Yoshida, Y. Kanzawa, S. Hayashi, K. Yamamoto, Appl. Phys. Lett. 71 (1997) 1198. [5] M. Nogami, T. Yamazaki, Y. Abe, J. Lumin. 78 (1998) 63. [6] L. Li, H. Li, M. Qian, M. Strachan, J. Non-Cryst. Solids 281 (2001) 189. [7] B. Sun, H. Song, J. Wang, H. Peng, X. Zhang, S. Lu, J. Zhang, H. Xia, Chem. Phys. Lett. 368 (2003) 412. [8] H. Xia, Q. Nie, J. Zhang, J. Wang, Mater. Lett. 57 (2003) 3895. [9] C.F. Song, P. Yang, M.K. Lu, D. Xu, D.R. Yuan, Z.Q. Liu, J. Phys. Chem. Solids 64 (2003) 491. [10] A.B. Corradi, V. Cannillo, M. Montorsi, C. Siligardi, J. Mater. Sci. 41 (2006) 2811. [11] P. Pascuta, M. Bosca, M. Culea, S. Simon, E. Culea, Mod. Phys. Lett. B 22 (2008) 447. [12] R.K. Brow, M.E. Schlesinger, L. Zhang, J. Non-Cryst. Solids 356 (2010) 25–27. [13] G. Boulon, M. Cohen-Adad, C. Dujardin, C. Goutaudier, N. Kbir-Ariguib, G. Panczer, R. Ternane, M. Trabelsi-Ayedi, Solid State Sci. 4 (2002) 53–59. [14] L. Koudelka, P. Mosner, Mater. Lett. 42 (2000) 194–199. [15] M. Scagliotti, M. Villa, G. Geiodell, J. Non-Cryst. Solids 93 (1987) 350. [16] L. Koudelka, J. Jirak, P. Mosner, L. Montagne, G. Palavit, J. Mater. Sci. 41 (2006) 4636–4642. [17] R. Kniep, H. Engelhardt, C. Hauf, Chem. Mater. 10 (1998) 2930–2934. [18] Y.M. Lai, X.F. Liang, S.Y. Yang, J. Mol. Struct. 992 (2011) 84–88. [19] B. Vijaya Kumar, T. Sankarappa, M. Prashant Kumar, Santosh Kumar, J. Non-Cryst. Solids 355 (2009) 229–234. [20] L. Koudelka, P. Mosner, J. Pospisil, L. Montagne, G. Palavit, J. Solid State Chem. 178 (2005) 1837–1843.

5

[21] C. Maurel, T. Cardinal, M. Bellec, L. Canioni, B. Bousquet, M. Treguer, J. Videau, J. Choi, M. Richardson, J. Lumin. 129 (2009) 1514–1518. [22] K. El-Egili, H. Doweidar, Y.M. Moustafa, I. Abbas, Phys. B Condens. Matter 339 (2003) 237. [23] J.S. Kumar, et al., J. Lumin. 130 (2010) 1916–1923. [24] J.L.H. Chau, et al., Mater. Lett. 61 (2007) 2908–2910. [25] A. Ivankov, J. Seekamp, W. Bauhofer, J. Lumin. 121 (2006) 123–131. [26] Y. Changha, G. Chunfang, L.P. Qiu Guanming, J. Rare Earths 25 (2007) 117. [27] H. Ebendorff-Heidepriem, W. Seeber, D. Ehrt, J. Non-Cryst. Solids 183 (1995) 191–200. [28] J.A. Sampaio, T. Catunda, A.A. Coelho, S. Gama, A.C. Bento, L.C.M. Miranda, M.L. Baesso, J. Non-Cryst. Solids 273 (2000) 239–245. [29] P.Y. Shih, Mater. Chem. Phys. 84 (2004) 151–156. [30] S.K. Singh, N.K. Giri, D.K. Rai, S.B. Rai, Solid State Sci. 12 (2010) 1480. [31] P.N. Prasad, Nanophotonics, Wiley, New York, 2004. [32] G. Fu, W. Cai, C. Kan, C. Li, L. Zhang, Appl. Phys. Lett. 83 (2003) 36. [33] T. Som, B. Karmalar, J. Opt. Soc. Am. B 26 (2009) B21. [34] D. Zhou, Zh. Song, G. Chi, J. Qiu, J. Alloys Compd. 481 (2009) 881. [35] L.R.P. Kassab, C.B. de Ara ْ jo, in: V.P. Nilsson (Ed.), Photonics Research Developments, Nova Science Publishers, New York 2008, pp. 385–409. [36] M. Reza Dousti, M.R. Sahar, S.K. Ghoshal, Raja J. Amjad, A.R. Samavati, J. Mol. Struct. 1035 (2013) 6–12. [37] A. Madzlan, S.A. Saad, W. RWB, W. ZWM, Mater. Lett. 74 (2012) 62–64. [38] T. Sekiya, N. Mochida, A. Ohtsuka, A. Soejima, J. Non-Cryst. Solids 151 (1992) 222. [39] R.T. Karunakaran, K. Marimuthu, S. SurendraBabu, S. Arumugam, Phys. B 404 (2009) 3995. [40] M.R. Sahar, N. Norrdin, J. Non-Cryst. Solids 184 (1995) 137.

Please cite this article as: H. Aboud, R.J. Amjad, SnO2 nanoparticles concentration dependent structural and luminescence characteristics of Er+3 doped zinc-lead-phosphate glass, J. Non-Cryst. Solids (2017), http://dx.doi.org/10.1016/j.jnoncrysol.2017.03.018