Sintering Behavior and Electrical Conductivity of Gd0.1Ce0.9O1.95 with Li2O Additives

doi:10.15541/jim20140452

Abstract

Abstract:

Cerium oxide-based materials are the most widely used electrolyte material for low-intermediate temperature Solid Oxide Fuel Cell (SOFC). In this study, the interaction between Li₂O and CeO₂ was calculated based on density functional theory (DFT). The results showed that the sintering of CeO₂ was positively affected by Li₂O. Based on this result, the actual sintering process of Gd_0.1Ce_0.9O_1.95(GDC) with different concentration (0-5mol%) of Li₂O additive was characterized through the sintering behavior and scanning electron microscope (SEM). The electrochemical performance was also being investigated simultaneously. The results show that the initial shrinkage temperature shifted to lower temperature significantly, and the temperature of the highest shrinkage rate also decreased with the increasing of the Li₂O additive content. The shrinking of GDC with 2.5mol% Li₂O started at 650 ℃, and the GDC electrolyte with higher than 99% relative density was obtained at a low sintering temperature of 900 ℃. The total electrical conductivity of GDC was improved with Li₂O additive. Meanwhile, the open circuit voltage of the corresponding single cell maintained nearly the same with pure GDC. These preliminary results indicate that Li₂O is a very effective sintering aid for cerium oxide-based electrolyte in SOFC.

Key words: cerium oxide-based electrolyte, sintering aid, solid oxide fuel cell

CLC Number:

TQ174

YANG Zhi-Bin, ZHU Teng-Long, XIANG Wen-Long, YU Li-An, HAN Min-Fang. Sintering Behavior and Electrical Conductivity of Gd_0.1Ce_0.9O_1.95 with Li₂O Additives[J]. Journal of Inorganic Materials, 2015, 30(4): 345-350.

Figures/Tables 9

Fig. 1 Calculation results optimized by BP86/TZVPP and TPSS/TZVPP (in brackets)

Fig. 2 Possible structures included 2CeO2+3Li2O and 2CeO2+ 4Li2O optimized by BP86/TZVPP and TPSS/TZVPP (in brackets)

Fig. 3 Sintering property of nmol% (n=0, 0.5, 1.5, 2.5, 5.0) Li2O-GDC

Fig. 4 Relationship between relative density and sintering temperatures of nmol% (n=0, 0.5, 1.5, 2.5, 5.0) Li2O-GDC

Table 1 The temperature of initial shrinkage and the highest shrink rate of Li2O-GDC

Temperature/℃	GDC	0.5mol%Li₂O-GDC	1.5mol%Li₂O-GDC	2.5mol%Li₂O-GDC	5mol%Li₂O-GDC
Initial shrinkage	1000	700	670	650	600
Highest shrink rate	1175	1170	920	800	750

Table 2 The lowest densification temperature of nmol% (n=0, 0.5, 1.5, 2.5, 5.0) Li2O-GDC

	GDC	0.5mol%Li₂O-GDC	1.5mol%Li₂O-GDC	2.5mol%Li₂O-GDC	5mol%Li₂O-GDC
Densification temperature/℃	1400	1400	1250	900	850

Fig. 5 Microstructure of nmol% (n=1.5, 2.5, 5.0) Li2O-GDC sintered at the lowest densification transition temperature Surface and cross section of 5mol%Li2O-GDC (a, b), 2.5mol%Li2O-GDC (c, d), 1.5mol%Li2O-GDC(e, f)

Fig. 6 Relationship of electrical conductivity with temperature of nmol% (n=0, 2.5, 5.0) Li2O-GDC samples

Table 3 OCV of NiO-GDC/2.5mol%Li2O-GDC/LSCF cell

Temperature/℃	2.5mol%Li₂O-GDC-900 ℃/V	GDC-1400℃/V
550	0.883	0.889
600	0.879	0.877
650	0.866	0.857
700	0.843	0.841

References 20

[1]	STEELE B C H. Materials for IT-SOFC stacks 35 years R&D: the inevitability of gradualness.Solid State Ionics, 2000, 134: 3-20.
[2]	YANG N T, MENG X X, TAN X Y, et al.Anode of intermediate temperature solid oxide fuel cells.Journal of Inorganic Materials, 2006, 21(2): 409-414.
[3]	KEEGAN C W, JOYCE S C.Taxonomies of SOFC material and manufacturing alternatives.Journal of Power Sources, 2005, 140: 280-296.
[4]	MACA K, CIHLAR J, CASTKOVA K, et al.Sintering of gadolinia-doped ceria prepared by mechanochemical synthesis.Journal of the European Ceramic Society, 2007, 27(13/14/15): 4345-4348.
[5]	ZHANG T, HING P, HUANG H, et al. Densification, microstructure and grain growth in the CeO2-Fe2O3 system(0≤Fe/Ce≤20%).Jour-nal of the European Ceramic Society, 2001, 21: 2221-2228.
[6]	JUD E, HUWILER C, GAUCKLER L J.Sintering analysis of undoped and cobalt oxide doped ceria solid solutions.Journal of the American Ceramic Society, 2005, 88(11): 3013-3019.
[7]	KLEINLOGEL C, GAUCKLER L J.Sintering of nanocrystalline CeO2 ceramics.Advanced Materials, 2001, 13: 1081-1085.
[8]	GUO Q Q, DAI L, WU Y L, et al.Effect of Li2O additions on properties of gadolinia-doped ceria ceramics. Journal of Functional Materials, 2009, 40(1): 101-106.
[9]	LE S R, ZHU S C, ZHU X D, et al.Densification of Sm0.2Ce0.8O1.9 with the addition of lithium oxide as sintering. Journal of Power Sources, 2013, 222: 367-372.
[10]	HAN M F, LIU Z, ZHOU S, et al.Infuence of lithium oxide addition on the sintering behavior and electrical conductivity of gadolinia doped ceria.Journal of Materials Science and Technology, 2011, 27(5): 460-464.
[11]	LEWIS G S, ATKINSON A, STEELE B C H, et al. Effect of Co addition on the lattice parameter, electrical conductivity and sintering of gadolinia-doped ceria. Solid State Ionics, 2002, 152/153: 567-573.
[12]	HAN M F, JIAO C R, XIONG J, et al.Properties of yttria doped zirconia electrolyte with Li2O additive.Journal of the Chinese Ceramic Society, 2012, 40(10): 1507-1514.
[13]	ZHU T L, LIN Y, YANG Z B, et al.Evaluation of Li2O as an efficient sintering aid for gadolinia-doped ceria electrolyte for solid oxide fuel cells. Journal of Power Sources, 2014, 261: 255-263.
[14]	FUENTES R O, BAKER R T.Synthesis and properties of gadolinium-doped ceria solid solutions for IT-SOFC electrolytes.International Journal of Hydrogen Energy, 2008, 33(13): 3480-3484.
[15]	BELLERT D, BRECKENRIDGE W H.A spectroscopic determination of the bond length of the LiOLi molecule: Strong ionic bonding.Journal of Chemical Physics, 2001, 114: 2871-2874.
[16]	PE´REZ-COLL D, NU´N˜EZ P, ABRANTES J C C, et al. Effects of firing conditions and addition of Co on bulk and grain boundary properties of CGO.Solid State Ionics, 2005, 176: 2799-2805.
[17]	LE S R, ZHU S C, ZHU X D, et al.Densification of Sm0.2Ce0.8O1.9 with the addition of lithium oxide as sintering aid.Journal of Power Sources, 2013, 222: 367-372.
[18]	TONG Q F, WANG J Y, LI Z P, et al.Low-temperature synthesis/densification and properties of Si2N2O prepared with Li2O additive.Journal of the European Ceramic Society, 2007, 27: 4767-4772.
[19]	NICHOLAS J D, DEJONGHE L C.Creating dense, constrained Ce0.9Gd0.1O1.95 films at low temperature for SOFC applications. Materials Research Society Proceedings, 2007, 1023: 1005-1009.
[20]	ZHANG T S, PETER H, HUANG H T, et al.Ionic conductivity in the CeO2-Gd2O3 system (0.05≤Gd/Ce≤0.4) prepared by oxalate coprecipitation.Solid State Ionics, 2002, 148: 567-573.

Sintering Behavior and Electrical Conductivity of Gd_0.1Ce_0.9O_1.95 with Li₂O Additives

RichHTML

PDF (PC)

Knowledge

Cited

Abstract

Cite this article

share this article

Figures/Tables 9

References 20

Related Articles 15

Recommended Articles

Metrics

Comments

[1]	PAN Jianlong, MA Guanjun, SONG Lemei, HUAN Yu, WEI Tao. High Stability/Catalytic Activity Co-based Perovskite as SOFC Anode: In-situ Preparation by Fuel Reducing Method [J]. Journal of Inorganic Materials, 2024, 39(8): 911-919.
[2]	YE Zibin, ZOU Gaochang, WU Qiwen, YAN Xiaomin, ZHOU Mingyang, LIU Jiang. Preparation and Performances of Tubular Cone-shaped Anode-supported Segmented-in-series Direct Carbon Solid Oxide Fuel Cell [J]. Journal of Inorganic Materials, 2024, 39(7): 819-827.
[3]	ZHANG Kun, WANG Yu, ZHU Tenglong, SUN Kaihua, HAN Minfang, ZHONG Qin. LaNi_0.6Fe_0.4O₃ Cathode Contact Material: Electrical Conducting Property Manipulation and Its Effect on SOFC Electrochemical Performance [J]. Journal of Inorganic Materials, 2024, 39(4): 367-373.
[4]	CHEN Zhengpeng, JIN Fangjun, LI Mingfei, DONG Jiangbo, XU Renci, XU Hanzhao, XIONG Kai, RAO Muming, CHEN Chuangting, LI Xiaowei, LING Yihan. Double Perovskite Sr₂CoFeO₅₊_δ: Preparation and Performance as Cathode Material for Intermediate-temperature Solid Oxide Fuel Cells [J]. Journal of Inorganic Materials, 2024, 39(3): 337-344.
[5]	XUE Dingxi, YI Bingyao, LI Guojun, MA Shuai, LIU Keqin. Numerical Simulation of Thermal Stress in Solid Oxide Fuel Cells with Functional Gradient Anode [J]. Journal of Inorganic Materials, 2024, 39(11): 1189-1196.
[6]	GUO Tianmin, DONG Jiangbo, CHEN Zhengpeng, RAO Mumin, LI Mingfei, LI Tian, LING Yihan. Enhanced Compatibility and Activity of High-entropy Double Perovskite Cathode Material for IT-SOFC [J]. Journal of Inorganic Materials, 2023, 38(6): 693-700.
[7]	FAN Shuai, JIN Tian, ZHANG Shanlin, LUO Xiaotao, LI Chengxin, LI Changjiu. Effect of Li₂O Sintering Aid on Sintering Characteristics and Electrical Conductivity of LSGM Electrolyte for Solid Oxide Fuel Cell [J]. Journal of Inorganic Materials, 2022, 37(10): 1087-1092.
[8]	CAO Dan,ZHOU Mingyang,LIU Zhijun,YAN Xiaomin,LIU Jiang. Fabrication and Characterization of Anode-supported Solid Oxide Fuel Cell Based on Proton Conductor Electrolyte [J]. Journal of Inorganic Materials, 2020, 35(9): 1047-1052.
[9]	HU Zewang,CHEN Xiaopu,LIU Xin,LI Xiaoying,SHI Yun,KOU Huamin,XIE Tengfei,LI Jiang. Trace SiO₂ Addition on Optical and Scintillation Property of Pr:Lu₃Al₅O₁₂ Ceramics [J]. Journal of Inorganic Materials, 2020, 35(7): 796-802.
[10]	XIA Tian, MENG Xie, LUO Ting, ZHAN Zhongliang. La ³⁺-substituted Sr₂Fe_1.5Ni_0.1Mo_0.4O_6-_δ as Anodes for Solid Oxide Fuel Cells [J]. Journal of Inorganic Materials, 2020, 35(5): 617-622.
[11]	Kai LI, Xiao LI, Jian LI, Jia-Miao XIE. Structural Stability of Ni-Fe Supported Solid Oxide Fuel Cells Based on Stress Analysis [J]. Journal of Inorganic Materials, 2019, 34(6): 611-617.
[12]	Wei WANG, Li-Li YUAN, Qian-Yuan QIU, Ming-Yang ZHOU, Mei-Lin LIU, Jiang LIU. A Direct Carbon Solid Oxide Fuel Cell Stack Based on a Single Electrolyte Plate Fabricated by Tape Casting Technique [J]. Journal of Inorganic Materials, 2019, 34(5): 509-514.
[13]	XIA Tian, MENG Xie, LUO Ting, ZHAN Zhong-Liang. Synthesis and Evaluation of Ca-doped Sr₂Fe_1.5Mo_0.5O_6-_δ as Symmetrical Electrodes for High Performance Solid Oxide Fuel Cells [J]. Journal of Inorganic Materials, 2019, 34(10): 1109-1114.
[14]	YUAN Kang, LIAO Qi-Long, WANG Fu, DAI Yun-Ya, HUANG Jin-Shan. Effects of Sintering Aids (Y³⁺, La³⁺ and Mg²⁺) on the Optical Transmittance of Translucent Alumina Ceramic [J]. Journal of Inorganic Materials, 2017, 32(9): 1004-1008.
[15]	XU Hong-Mei, ZHANG Hua, LI Heng, JIAN Yao-Yong, XIE Wu, WANG Yi-Ping, XU Ming-Ze. Preparation and Oxygen-reduction Mechanism Investigation of Nanostructure LSCF-SDC Composite Cathodes [J]. Journal of Inorganic Materials, 2017, 32(4): 379-385.