A Raman Spectroscopic Study of the Structural Modifications Associated with the Addition of Calcium Oxide and Boron Oxide to Silica

Kline, Jeff; Tangstad, Merete; Tranell, Gabriella

doi:10.1007/s11663-014-0194-9

Cited by 32 publications

(8 citation statements)

References 34 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…As plotted in Figure 4, the mole fractions of Q 3 (Si) considerably increased at the cost of SiO 4 tetrahedral with more non-bridging oxygens, especially Q 0 (Si) and Q 2 (Si), with increasing B 2 O 3 content, which was in agreement with a recent study by Kline et al [32] This indicated that the added B 2 O 3 gave rise to a higher DOP of the networks, as also verified by the FTIR spectra. Thus it can be further concluded that the added B 2 O 3 acted as a typical network former in the present glasses.…”

Section: Yongqi Sun and Zuotai Zhangsupporting

confidence: 92%

Structural Roles of Boron and Silicon in the CaO-SiO2-B2O3 Glasses Using FTIR, Raman, and NMR Spectroscopy

Sun

Zhang

2015

Metall Mater Trans B

View full text Add to dashboard Cite

The present paper provided not only a deep insight of network structures of borosilicate glasses but also a basic linkage between the network structures and the viscous flow behaviors of many borosilicate melts. The structures of a ternary system of CaO-SiO 2 -B 2 O 3 were characterized using Fourier transformation infrared (FTIR), Raman, and magic angular spinning nuclear magnetic resonance spectroscopy. The results of FTIR and Raman spectra complementally verified that the main Si-related units were SiO 4 tetrahedral with zero, one, two, and three bridging oxygens [Q 0 (Si), Q 1 (Si), Q 2 (Si), and Q 3 (Si)]; the added B 2 O 3 leaded to an increase of Q 3 (Si) at the cost of Q 0 (Si) and Q 2 (Si), and therefore an increasing degree of polymerization (DOP) was induced. Additionally, the 11 B NMR spectra demonstrated that the dominant B-related groups were BO 3 trigonal and BO 4 tetrahedral, while an increasing B 2 O 3 content facilitated the existence of BO 4 tetrahedral. Moreover, there was a competitive effect between the enhanced DOP and the presence of BO 3 trigonal and BO 4 tetrahedral in the networks, which therefore resulted in a decreasing viscosity of borosilicate melts in numerous studies.Borosilicate-based glasses and melts are important materials because of their wide applications in glass industry. [1][2][3][4] and metallurgical industry. [5][6][7][8][9] The macroscopic properties of these glasses and melts are primarily determined by the microscopic structure; thus it is of crucial importance to acquire the structural environments of boron (B) and silicon (Si) including the role and coordination conditions. Meanwhile, numerous studies [5][6][7][10][11][12][13][14][15][16][17] explored the viscous flow behavior and analyzed the variation trend of the viscosities of B 2 O 3 -bearing melts. The foregoing investigations on the structures and viscosities of borosilicate glasses and melts could be categorized into three types.First, many researchers [6,[10][11][12][13][14][15][16] measured the viscosity of borosilicate melts and discovered that the viscosity remarkably or slightly decreased with increasing B 2 O 3 content depending on the melt components, while the discussion on the varying viscosity was focused on the overall nature of B 2 O 3 with a low-melting point. Second, recently several studies [5,7,17] investigated the viscosities of boron-bearing melts from the prospect of qualitative analysis of the melt structures using Fourier transformation infrared (FTIR) and Raman spectra. Third, because of the crucial importance of borosilicate glasses, many studies have explored the structures of borosilicate glasses [1][2][3][4] and substantial knowledge has been obtained.As for the Si-related structures, there were five structural units of SiO 4 tetrahedral, [18][19][20][21] which could be denoted as Q i (Si) (i = 0, 1, 2, 3, 4), where i represents the number of bridging oxygens (BO). The mole fraction of these structural units could be derived based on the deconvolutions of the Raman or magic angular...

show abstract

Section: Yongqi Sun and Zuotai Zhangsupporting

confidence: 92%

Structural Roles of Boron and Silicon in the CaO-SiO2-B2O3 Glasses Using FTIR, Raman, and NMR Spectroscopy

Sun

Zhang

2015

Metall Mater Trans B

View full text Add to dashboard Cite

show abstract

“…The schematic of the various borate structural units adapted from previous reports is depicted in Figure 2 32,34 and the structural change from silicate network structures to boro-silicate network structures by B 2 O 3 additions is depicted in Figure 3. 9,27,28,32,[35][36][37] The structural analyses were performed at least three times to estimate the standard errors; the standard errors of the deconvoluted area of Raman spectroscopy are the differences between the observed spectra and the fitted spectra by Peakfit v4 program (AISN software Inc., United Kingdom). Within the present study, structural analysis of as-quenched glassy fluxes from 1673 K (1400°C) was conducted using a combination of FTIR and Raman spectroscopy.…”

Section: Raman Spectroscopymentioning

confidence: 99%

Effect of CaF₂, B₂O₃ and the CaO/SiO₂ mass ratio on the viscosity and structure of B₂O₃‐containing calcium‐silicate‐based melts

Kim

Sohn

2019

J Am Ceram Soc

View full text Add to dashboard Cite

The relationship between the viscosity and structure of B 2 O 3 -containing calciumsilicate-based mold fluxes and the effects of fluidizers including CaF 2 , CaO, and B 2 O 3 on the viscosity and their correlation with the structural aspects were studied using a rheometer with Fourier transformation infrared and Raman spectroscopy.The viscosity decreased with increasing CaF 2 addition up to 28 wt% at a fixed CaO/ SiO 2 ratio of 0.3, which was related to depolymerization. Furthermore, CaF 2 addition also affected the apparent activation energy for viscous flow, which decreased with increasing CaF 2 content to 105.1 from 151.1 kJ/mol. At higher C/S ratios, the viscosity decreased in the presence of greater Ca 2+ and O 2− supplied from CaO, which subsequently increased the activation energy to 149.7 from 122.0 kJ/mol.With regard to the B 2 O 3 -melt, polymerization of the network structure was observed by comparing the B 2 O 3 -free to 4.4 wt% B 2 O 3 content. However, the viscosity was relatively constant with increasing B 2 O 3 addition. However, the viscosity decreased due to greater simplification of the network structure above 4.4 wt% B 2 O 3 . The break temperature decreased with greater B 2 O 3 addition as the crystallization was inhibited. Furthermore, the apparent activation energy decreased as depolymerization of the network structures occurred above 4.4 wt% B 2 O 3 . K E Y W O R D SB 2 O 3 , CaF 2 , CaO/SiO 2 mass ratio, mold flux, network structure, viscosity

show abstract

“…Sakamoto et al [36] found that the increasing theoretical optical basicity leads to the distinct decrease of the relative fraction of [BO 4 ] and decreases the activity of B 2 O 3 in slag. As investigated by Kline et al, [37] the increasing B 2 O 3 content in slag leads to the transformation from Q 2 species to Q 3 , and the B cation is more likely to react with basic oxygens. Similar results have also been reported by Qian et al [38] that the Q 0 , Q 1 , and Q 2 species play an important role in incorporating B into the Si network and facilitate the formation of Q 3 species when the optical basicity of a CaO-Na 2 O-SiO 2 slag is lower than 0.66.…”

Section: Introductionmentioning

confidence: 89%

Effects of La2O3 Addition into CaO-SiO2 Slag: Structural Evolution and Impurity Separation from Si-Sn Alloy

Zhu

Azarov

et al. 2021

Metall Mater Trans B

View full text Add to dashboard Cite

Boron (B) and phosphorus (P) are the most problematic impurities to be removed in the production of solar-grade silicon by the metallurgical process. In this work, the distribution of B and P between CaO-(La2O3)-SiO2 slags and Si-10 mass pct Sn melt was experimentally studied. B distribution coefficient increased from 2.93 in binary CaO-SiO2 slag to 3.33 and 3.65 with 2 and 10 mass pct La2O3 additions, respectively. In the followed acid-leaching experiments, the slag-treated Si-Sn alloys exhibited higher B and P removal than that of the initial alloy without slag treatment. Molecular dynamics simulations were performed to study the effect of La2O3 addition on the slag structural and transport properties. A novel oxygen classification method was proposed to distinguish the different structural roles of La and Ca in the CaO-La2O3-SiO2 system. It was found that La3+ prefers to stay in the depolymerized region, mostly connects with 6-7 non-bridging oxygen, and requires a weak charge compensation with Ca2+. Possible silicothermic reduction was evaluated to discuss the slag chemistry and the mass transfer between slag and metal phase. A thermodynamic model was derived to theoretically study the alloying effect on impurity distribution in slag refining where positive interaction coefficient and high alloying concentration were found most beneficial to improve the impurity removal.

show abstract

A Raman Spectroscopic Study of the Structural Modifications Associated with the Addition of Calcium Oxide and Boron Oxide to Silica

Cited by 32 publications

References 34 publications

Structural Roles of Boron and Silicon in the CaO-SiO2-B2O3 Glasses Using FTIR, Raman, and NMR Spectroscopy

Structural Roles of Boron and Silicon in the CaO-SiO2-B2O3 Glasses Using FTIR, Raman, and NMR Spectroscopy

Effect of CaF₂, B₂O₃ and the CaO/SiO₂ mass ratio on the viscosity and structure of B₂O₃‐containing calcium‐silicate‐based melts

Effects of La2O3 Addition into CaO-SiO2 Slag: Structural Evolution and Impurity Separation from Si-Sn Alloy

Contact Info

Product

Resources

About

A Raman Spectroscopic Study of the Structural Modifications Associated with the Addition of Calcium Oxide and Boron Oxide to Silica

Cited by 32 publications

References 34 publications

Structural Roles of Boron and Silicon in the CaO-SiO2-B2O3 Glasses Using FTIR, Raman, and NMR Spectroscopy

Structural Roles of Boron and Silicon in the CaO-SiO2-B2O3 Glasses Using FTIR, Raman, and NMR Spectroscopy

Effect of CaF2, B2O3 and the CaO/SiO2 mass ratio on the viscosity and structure of B2O3‐containing calcium‐silicate‐based melts

Effects of La2O3 Addition into CaO-SiO2 Slag: Structural Evolution and Impurity Separation from Si-Sn Alloy

Contact Info

Product

Resources

About

Effect of CaF₂, B₂O₃ and the CaO/SiO₂ mass ratio on the viscosity and structure of B₂O₃‐containing calcium‐silicate‐based melts