ZrO2 Solid Electrolyte Aided Investigation on Electrodeposition in Na3AlF6-SiO2 Melt

doi:10.11900/0412.1961.2021.00132

Acta Metall Sin

2022, Vol. 58

Issue (10): 1292-1304 DOI: 10.11900/0412.1961.2021.00132

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ZrO₂ Solid Electrolyte Aided Investigation on Electrodeposition in Na₃AlF₆-SiO₂ Melt

GAO Yunming¹^,²(

), HE Lin¹^,², QIN Qingwei¹^,², LI Guangqiang¹^,²

^1.The State Key Laboratory of Refractories and Metallurgy, Wuhan University of Science and Technology, Wuhan 430081, China
^2.Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education, Wuhan University of Science and Technology, Wuhan 430081, China

Cite this article:

GAO Yunming, HE Lin, QIN Qingwei, LI Guangqiang. ZrO₂ Solid Electrolyte Aided Investigation on Electrodeposition in Na₃AlF₆-SiO₂ Melt. Acta Metall Sin, 2022, 58(10): 1292-1304.

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Abstract

Electrodeposition of silicon from a cryolite-based melt is a possible solution for the mass production of silicon with high purity. Currently, deposition of Si from dissolved SiO₂ in cryolite-based melts occurs primarily in a graphite crucible using graphite and quasi-reference electrodes, resulting in series of problems, such as CO _x emissions due to carbon participation, non-significant peak positions on cyclic voltammetry (CV) curves due to melt electronic conduction, various reference standards of metal deposition potential, and insufficient investigations on electrode reaction mechanism due to melt composition complexity. In this work, a novel three-electrode electrochemical cell with Pt, O₂(air)|YSZ reference (RE), and counter electrodes (CE) was constructed using a Y₂O₃ stabilized ZrO₂ solid electrolyte (YSZ) tube, CV and potentiostat electrolysis tests were performed on Ir wire working electrode in Na₃AlF₆-5%SiO₂ (mass fraction) melt under the conditions of a complete carbon-free and 1323 K. The precipitation potentials of related metals on the cathode in the melt were investigated, and the electrodeposition law in the melt at different potentials was analyzed, using a combination of thermodynamic theoretical calculations, SEM observation, and EDS analysis. The results show that Si can be deposited on the Ir wire in a single step, and its peak potential is about -1.65 V on the CV curve, while the deposition potentials of Al, Na (Zr) are all negative than -1.8 V and increase negatively in turn. During potentiostatic electrolysis, intermetallic compound particles of Zr₅Si₄ are observed to generate at -1.8 V or -2.0 V, with a generation potential of -1.7 V to -1.8 V. The deposited Si, Al, and Na metals are mainly derived from oxygen-containing compounds produced by the Na₃AlF₆-SiO₂ melt itself but Zr metal from the ZrO₂ of the corrosion of YSZ tubes by the melt. The precipitation potentials of related metals (or intermetallic compounds) relative to Pt, O₂(air)∣YSZ RE agree well with thermodynamic calculations.

Key words: silicon silica cryolite zirconia solid electrolyte electrodeposition

Received: 21 March 2021

ZTFLH:

TF89

Fund: National Natural Science Foundation of China(51174148)

About author: GAO Yunming, professor, Tel: (027)68862529, E-mail: gaoyunming@wust.edu.cn

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	Guangqiang LI

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https://www.ams.org.cn/EN/10.11900/0412.1961.2021.00132 OR https://www.ams.org.cn/EN/Y2022/V58/I10/1292

Fig.1 Schematic diagram of electrochemical cell device

Fig.2 Curve of open circuit potential vs time for Na₃AlF₆-5%SiO₂ melt at 1323 K (RE: Pt, O₂(air)| YSZ)

Table 1 Chemical reactions involving oxides and standard Gibbs energy (ΔG^Θ) and potential data at 1323 K^[33]

Fig.3 Cyclic voltammetry (CV) curves of Na₃AlF₆-SiO₂ melt on the Ir WE at the scan rate of 30 mV/s (RE: Pt, O₂(air)|YSZ)

Fig.4 Curves of current vs time during potentiostatic electrolysis for Na₃AlF₆-SiO₂ melt (RE: Pt, O₂(air)|YSZ)

Fig.5 SEM images of cross section (a1) of the Ir electrode and local magnification (a2), sediment particles (b1) at the bottom of YSZ tube and local magnification (b2) after electrolysis for pure Na₃AlF₆ melt at -2.2 V

Table 2 EDS results corresponding to the points in Fig.5

Fig.6 SEM images and scanline results of the Ir electrode section after electrolysis for Na₃AlF₆-5%SiO₂ melt at constant potentials of -1.4 V (a), -1.6 V (b), -1.8 V (c), and -2.0 V (d)

Table 3 EDS results corresponding to the points in Fig.6

Fig.7 SEM images of cross section of the Ir electrode vicinity after electrolysis of the melt at constant potentials of -1.4 V (a), -1.6 V (b), -1.8 V (c), and -2.0 V (d)

Table 4 EDS results corresponding to the points in Fig.7

Fig.8 Standard Gibbs free energy ΔG^Θ and temperature T of oxidation reactions for Zr and Zr₅Si₄

1	Xu J L, Haarberg G M. Electrodeposition of solar cell grade silicon in high temperature molten salts [J]. High Temp. Mater. Proc., 2013, 32: 97 doi: 10.1515/htmp-2012-0045
2	Elwell D, Feigelson R S. Electrodeposition of solar silicon [J]. Sol. Energy Mater., 1982, 6: 123 doi: 10.1016/0165-1633(82)90014-4
3	Elwell D, Rao G M. Electrolytic production of silicon [J]. J. Appl. Electrochem., 1988, 18: 15 doi: 10.1007/BF01016199
4	Sokhanvaran S, Barati M. Electrochemical behavior of silicon species in cryolite melt [J]. J. Electrochem. Soc., 2014, 161: E6 doi: 10.1149/2.042401jes
5	Sokhanvaran S, Danaei A, Barati M. Determination of cell potential for silicon electrodeposition [J]. Metall. Mater. Trans., 2014, 1E: 187
6	Sokhanvaran S, Thomas S, Barati M. Charge transport properties of cryolite-silica melts [J]. Electrochim. Acta, 2012, 66: 239 doi: 10.1016/j.electacta.2012.01.077
7	Jia M, Lai Y Q, Tian Z L, et al. Electrodeposition behavior of silicon from Na₃AlF₆-LiF melts [J]. Acta Phys.-Chim. Sin., 2011, 27: 1108 doi: 10.3866/PKU.WHXB20110504
	贾明, 赖延清, 田忠良等. Na₃AlF₆-LiF熔盐体系中硅的电沉积行为 [J]. 物理化学学报, 2011, 27: 1108
8	Korenko M, Vasková Z, Šimko F, et al. Electrical conductivity and viscosity of cryolite electrolytes for solar grade silicon (Si-SoG) electrowinning [J]. Trans. Nonferr. Met. Soc., 2014, 24: 3944 doi: 10.1016/S1003-6326(14)63554-8
9	Suzuki Y, Inoue Y, Yokota M, et al. Effects of oxide ions on the electrodeposition process of silicon in molten fluorides [J]. J. Electrochem. Soc., 2019, 166: D564 doi: 10.1149/2.0441913jes
10	Hu Y J, Wang X, Xiao J S, et al. Electrochemical behavior of silicon (IV) ion in BaF₂-CaF₂-SiO₂ melts at 1573K [J]. J. Electrochem. Soc., 2013, 160: D81 doi: 10.1149/2.038303jes
11	Sakanaka Y, Goto T. Electrodeposition of Si film on Ag substrate in molten LiF-NaF-KF directly dissolving SiO₂ [J]. Electrochim. Acta, 2015, 164: 139 doi: 10.1016/j.electacta.2014.12.159
12	De Mattei R C, Elwell D, Feigelson R S. Electrodeposition of silicon at temperatures above its melting point [J]. J. Electrochem. Soc., 1981, 128: 1712 doi: 10.1149/1.2127716
13	Haarberg G M, Famiyeh L, Martinez A M, et al. Electrodeposition of silicon from fluoride melts [J]. Electrochim. Acta, 2013, 100: 226 doi: 10.1016/j.electacta.2012.11.052
14	Monnier R, Giacometti J C. Recherches sur le raffinage électrolytique du silicium [J]. Helv. Chim. Acta, 1964, 47: 345 doi: 10.1002/hlca.19640470202
15	Suzdaltsev A V, Pershin P S, Filatov A A, et al. Review—Synthesis of aluminum master alloys in oxide-fluoride melts: A review [J]. J. Electrochem. Soc., 2020, 167: 102503 doi: 10.1149/1945-7111/ab9879
16	Liu A M, Shi Z N, Xu J L, et al. Preparation of Al-Si master alloy by electrochemical reduction of volcanic rock in cryolite molten salt [J]. JOM, 2016, 68: 1518 doi: 10.1007/s11837-016-1898-x
17	Oishi T, Watanabe M, Koyama K, et al. Process for solar grade silicon production by molten salt electrolysis using aluminum-silicon liquid alloy [J]. J. Electrochem. Soc., 2011, 158: E93 doi: 10.1149/1.3605720
18	Yu X G, Qiu Z X. Preparation of Al-Si alloy by molten salt electrolysis [J]. J. Northeast. Univ. (Nat. Sci.), 2004, 25: 442
	于旭光, 邱竹贤. 熔盐电解法制取Al-Si合金 [J]. 东北大学学报(自然科学版), 2004, 25: 442
19	Li M, Li Y, Wang Z W. Electrochemical reduction of zirconium oxide and Co-deposition of Al-Zr alloy from cryolite molten salt [J]. J. Electrochem. Soc., 2019, 166: D65 doi: 10.1149/2.1291902jes
20	Bao Morigengaowa. Preparation of Al-Zr alloys by molten salt electrolysis [D]. Shenyang: Northeastern University, 2015
	包莫日根高娃. 熔盐电解法制备铝锆合金的研究 [D]. 沈阳: 东北大学, 2015
21	Wang C Z. Solid Electrolyte and Chemical Sensors [M]. Beijing: Metallurgical Industry Press, 2000: 259
	王常珍. 固体电解质和化学传感器 [M]. 北京: 冶金工业出版社, 2000: 259
22	Gao Y M, Song J X, Zhang Y Q, et al. Measurement of the diffusivity of oxygen in high-temperature liquid silver by electrochemical method [J]. Acta Metall. Sin., 2010, 46: 277 doi: 10.3724/SP.J.1037.2010.00277
	高运明, 宋建新, 张业勤等. 利用电化学方法测定高温银液中氧的扩散系数 [J]. 金属学报, 2010, 46: 277 doi: 10.3724/SP.J.1037.2009.00579
23	Hong C, Gao Y M, Yang C H, et al. Electrochemical behavior of Ni²⁺ in SiO₂-CaO-MgO-Al₂O₃ molten slag at 1673 K [J]. Acta Metall. Sin., 2015, 51: 1001
	洪川, 高运明, 杨创煌等. 1673 K下SiO₂-CaO-MgO-Al₂O₃熔渣中Ni²⁺的电化学行为 [J]. 金属学报, 2015, 51: 1001
24	Hu H B, Gao Y M, Lao Y G, et al. Yttria-stabilized zirconia aided electrochemical investigation on ferric ions in mixed molten calcium and sodium chlorides [J]. Metall. Mater. Trans., 2018, 49B: 2794
25	Gao Y M, Yang C H, Zhang C L, et al. Magnesia-stabilised zirconia solid electrolyte assisted electrochemical investigation of iron ions in a SiO₂-CaO-MgO-Al₂O₃ molten slag at 1723 K [J]. Phys. Chem. Chem. Phys., 2017, 19: 15876 doi: 10.1039/C7CP01945A
26	Gao Y M, Huang Z B, He L, et al. Yttria-stabilized zirconia assisted green electrochemical preparation of silicon from solid silica in calcium chloride melt [J]. Metall. Mater. Trans., 2021, 52B: 1708
27	Zaykov Y P, Isakov A V, Zakiryanova I D, et al. Interaction between SiO₂ and a KF-KCl-K₂SiF₆ melt [J]. J. Phys. Chem., 2014, 118B: 1584
28	Monnier R, Barakat D. Contribution à l'étude du comportement de la silice dans les bains de cryolithe fondue [J]. Helv. Chim. Acta, 1957, 40: 2041 doi: 10.1002/hlca.19570400706
29	Bøe G, Grjotheim K, Matiašovský K, et al. Electrolytic deposition of silicon and of silicon alloys Part II: Decomposition voltages of components and current efficiency in the electrolysis of the Na₃AlF₆-Al₂O₃-SiO₂mixtures [J]. Can. Metall. Quart., 1971, 10: 179 doi: 10.1179/cmq.1971.10.3.179
30	Bøe G, Grjotheim K, Matiašovský K, et al. Electrolytic deposition of silicon and of silicon alloys Part III: Deposition of silicon and aluminum using a copper cathode [J]. Can. Metall. Quart., 1971, 10: 281 doi: 10.1179/cmq.1971.10.4.281
31	Grjotheim K, Matiašovský K, Fellner P, et al. Electrolytic deposition of silicon and of silicon alloys Part I: Physicochemical properties of the Na₃AlF₆-Al₂O₃-SiO₂ mixtures [J]. Can. Metall. Quart., 1971, 10: 79 doi: 10.1179/cmq.1971.10.2.79
32	Bøe G, Grjotheim K, Matiašovský K, et al. Electrolytic deposition of silicon and of silicon alloys. Part IV: Preparation of alloys with a high content of silicon, and silicon refining [J]. Can. Metall. Quart., 1972, 11: 463 doi: 10.1179/cmq.1972.11.3.463
33	FactSage. com [EB/OL]. [2021-03-20].
34	Liu A M, Guan J Z, Xie K Y, et al. Aluminothermic reduction-molten salt electrolysis of silica in cryolite melts [J]. J. Northeast. Univ. (Nat. Sci.), 2016, 37: 522
	刘爱民, 管晋钊, 谢开钰等. 冰晶石熔盐介质中铝热还原-熔盐电解二氧化硅 [J]. 东北大学学报(自然科学版), 2016, 37: 522
35	Well D F, Fyfe W S. The 1010 and 800^oC isothermal section in the system Na₃AlF₆-Al₂O₃-SiO₂ [J]. J. Electrochem. Soc., 1964, 111: 582 doi: 10.1149/1.2426187
36	Bao M G, Wang Z W, Gao B L, et al. Solubility of ZrO₂ in cryolite-based molten salt system [J]. Adv. Mater. Res., 2014, 968: 67
37	Hou H J, Yang H C, Huangfu G L, et al. Factors affecting the loss on ignition of cryolite [J]. Light Met., 2004, (2): 10
	侯红军, 杨华春, 皇甫根利等. 冰晶石灼减的影响因素 [J]. 轻金属, 2004, (2): 10
38	Franke P, Neuschütz D. [Landolt-Börnstein—Group IV Physical Chemistry] Binary Systems. Part 4: Binary Systems from Mn-Mo to Y-Zr\|\| Si-Zr [M], 2006, 19B4: 1
39	Murray J L, Mcalister A J. The Al-Si (aluminum-silicon) system [J]. Bull. Alloy Phase Diagrams, 1984, 5: 74 doi: 10.1007/BF02868729
40	Chen G Z, Fray D J. Invention and fundamentals of the FFC Cambridge process [A]. Extractive Metallurgy of Titanium [M]. Amsterdam: Elsevier, 2020: 227
41	Gratz E S, Milshtein J D, Pal U B. Determining yttria-stabilized zirconia (YSZ) stability in molten oxy-fluoride flux for the production of magnesium with the SOM process [J]. J. Am. Ceram. Soc., 2013, 96: 3279 doi: 10.1111/jace.12449

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