| 157 | 1 | 527 |
| 下载次数 | 被引频次 | 阅读次数 |
针对固体氧化物燃料电解池(SOEC)中二氧化碳还原反应(CO_2RR)效率低的问题，提出了一种双重调控策略：在Sr_2FeCo0.7Mo0.3O6–δ氧化物中掺杂氟离子并引入A位缺陷来优化电极材料性能。采用乙二胺四乙酸与柠檬酸复合溶胶–凝胶法制备了一系列改性电极，并通过多种表征手段系统研究了材料结构与性能的演变规律。结果发现：氟掺杂与A位缺陷的协同作用显著改变了材料的晶格结构，使氧空位浓度提高，同时增强了氧离子传输能力。Sr1.95Fe Co0.7Mo0.3F0.1O5.9–δ材料的氧空位浓度，在CO2吸附和电解方面的性能分别提升了125%和66.7%，极化电阻降低了73.2%。该电极材料在700～850℃表现出优越的CO_2RR催化活性，并且在120 h连续运行测试中衰减仅为7%。本工作不仅为开发高效SOEC阴极材料提供了新思路，也证实了氧位阴离子掺杂是提高钙钛矿氧化物电化学性能的有效策略。
Abstract：Introduction In view of the problems of easy oxidation and carbon deposition of conventional electrode materials in the actual working environment of SOEC,as well as the lack of understanding of the structure-activity relationship between oxygen vacancies and electrode performance of the existing materials,a dual regulation strategy of simultaneous doping of fluoride ion(F~-) and introducing A-site defects in Sr_2FeCo0.7Mo0.3O6-δ oxide was investigated.The crystal structure,electronic structure,chemical stability and other aspects of electrode materials were optimized to overcome the limitations of traditional materials and develop high-performance SOEC cathode materials.The influence mechanism of the dual regulation strategy on the key factors(i.e.,oxygen vacancy concentration,ion transport capacity and surface chemical properties) of the material was explored.It was expected that the adsorption and activation ability of the material to CO2 could be enhanced,the electrode overpotential could be reduced,and the electrode reaction rate could be improved via increasing the oxygen vacancy concentration,enhancing the oxygen ion transport capacity and optimizing the surface chemical state,thereby significantly improving the catalytic activity and electrolysis efficiency of CO_2RR,realizing the efficient conversion and utilization of carbon dioxide,and providing technical support for alleviating greenhouse gas emissions and energy crisis.Methods A series of Sr_2FeCo0.7Mo0.3O6-δ based electrode materials and related powders were prepared by an improved EDTA-citric acid composite sol-gel method.In the preparation process,the raw material ratio and reaction conditions were accurately controlled.For the preparation of A-site defect samples by adjusting the stoichiometric ratio of strontium source,and for the preparation of fluorine-containing samples by replacing part of Sr(NO3)2 with SrF2 as fluorine source and strontium source,all the samples were calcined under the same conditions to ensure the comparability of experimental results.Also,the LSGM electrolyte sheet was prepared by a tape casting method,and the LDC buffer layer was prepared by a sol-gel method.The symmetrical battery was assembled by a screen printing process.The printing thickness and sintering temperature of each functional layer were strictly controlled to ensure the structural integrity and interface bonding quality of the battery.Results and discussion The prepared materials are analyzed by advanced characterization techniques and experimental methods.The analysis of X-ray diffraction patterns clearly shows the crystal structure change of the material.Fluorine doping causes a lattice expansion,while the introduction of A-site defects causes a lattice contraction,and effectively inhibits the precipitation of SrF2 secondary phase.The analysis of X-ray photoelectron spectroscopy further reveals a significant change in the chemical state of the material surface.The fluorine element is effectively incorporated into the lattice,and the lattice Sr ratio is greatly increased,which effectively reduces the surface segregation of Sr and enhanced the stability of the material.Also,the decrease of the valence state of the B-site transition metal increases the number of d-orbital electrons,thus improving the electrocatalytic activity of the material.The increase of the relative content of adsorbed oxygen also indicates that the concentration of oxygen vacancies increases,which creates favorable conditions for ion transport and CO2 adsorption activation.The analysis of CO2 adsorption and thermal stability,temperature-pro grammed desorption and thermogravimetric experiments shows that the synergistic effect of fluorine doping and A-site defects greatly improves the desorption temperature,desorption amount and anti-carbonation ability of the material for CO2.The desorption amount of SFCMAF sample is 2.25 times greater than that of SFCM sample.The electron paramagnetic resonance characterization also confirms that SFCMAF has the maximum oxygen vacancy concentration,providing a great support for efficient CO2 electrolysis reaction.The results of electrochemical performance test indicate that the current density of SFCMAF material is 66.7% higher than that of the original material,and the performance of each sample improves and the amplitude is similar for CO2/H_2O co-electrolysis under the working conditions of 850℃ and 2 V.The analysis of electrochemical impedance spectroscopy and distribution relaxation time shows that the polarization resistance of SFCMAF reduces and the surface catalytic activity enhances.The SFCMAF electrode has a superior stability in both short-term and long-term stability tests,with only 7% decay in 120 h long-term test.The calculations based on the density functional theory indicate the essential reasons for the performance improvement in micron scale.SFCMAF has a stronger ability to adsorb and activate CO2.Fluorine doping and A-site defects synergistically optimize the electronic structure,reduce the oxygen vacancy formation energy,and change the electronic structure of the active site,which is highly consistent with the experimental results,and provides a solid theoretical guidance for further optimizing the material properties.Conclusions This study developed a high-performance SOEC cathode material via introducing fluoride ion doping and A-site defects in Sr_2FeCo0.7Mo0.3O6-δ matrix.The modified material maintained a basic double perovskite structure with significant changes in lattice parameters.The dual-regulation strategy improved the surface chemical properties,CO2 adsorption,and electrochemical performance.The oxygen vacancy concentration increased,and the polarization resistance decreased.The theoretical calculations revealed the mechanism of performance improvement.This strategy could provide some ideas for designing efficient SOEC cathode materials and validate the effectiveness of anion doping combined with cation defect regulation.
[1] SU C, WANG W, LIU M L, et al. Progress and prospects in symmetrical solid oxide fuel cells with two identical electrodes[J]. Adv Energy Mater, 2015, 5(14):1500188.
[2] SHEN Y F, SONG Y, ZHAO Y X, et al. Mo-doped Ba0.5Sr0.5Co0.8Fe0.2O3-δ as a high-performance symmetric electrode for solid oxide fuel cells[J]. J Alloys Compd, 2022, 928:167029.
[3] ZHANG Y, CHEN B, GUAN D Q, et al. Thermal-expansion offset for high-performance fuel cell cathodes[J]. Nature, 2021, 591(7849):246–251.
[4] SHIMADA H, YAMAGUCHI T, KISHIMOTO H, et al. Nanocomposite electrodes for high current density over 3 A cm-2 in solid oxide electrolysis cells[J]. Nat Commun, 2019, 10(1):5432.
[5] YAJIMA T, TAKEIRI F, AIDZU K, et al. A labile hydride strategy for the synthesis of heavily nitridized BaTiO3[J]. Nat Chem, 2015, 7(12):1017–1023.
[6] BIKBAEVA V, NESTERENKO N, KONNOV S, et al. A low carbon route to ethylene:Ethane oxidative dehydrogenation with CO2 on embryonic zeolite supported Mo-carbide catalyst[J]. Appl Catal B Environ, 2023, 320:122011.
[7] CHEN D K, BARREAU M, TURCZYNIAK-SURDACKA S, et al.Ceria nanoparticles as promoters of CO2 electroreduction on Ni/YSZ:An efficient preparation strategy and insights into the catalytic promotion mechanism[J]. Nano Energy, 2022, 101:107564.
[8] LIU C Y, LI S T, GAO J Q, et al. Enhancing CO2 catalytic adsorption on an Fe nanoparticle-decorated LaSrFeO4+δ cathode for CO2electrolysis[J]. ACS Appl Mater Interfaces, 2021, 13(7):8229–8238.
[9] WANG R J, LIU S S, LI Q W, et al. CO2 capture performance and mechanism of blended amine solvents regulated by N-methylcyclohexyamine[J].Energy, 2021, 215:119209.
[10] GU J M, ZHANG X X, ZHAO Y X, et al. Advances and challenges in symmetrical solid oxide electrolysis cells:Materials development and resource utilization[J]. Mater Chem Front, 2023, 7(18):3904–3921.
[11] LI P, LIU F, YANG B B, et al. Enhanced electrochemical redox kinetics of La0.6Sr0.4Co0.2Fe0.8O3 in reversible solid oxide cells[J].Electrochim Acta, 2023, 446:142069.
[12] CHENG Y, WU X, VEDER J P, et al. Tuning the electrochemical property of the ultrafine metal-oxide nanoclusters by iron phthalocyanine as efficient catalysts for energy storage and conversion[J]. ENERGY ENVIRONMENTAL Mater, 2019, 2(1):5–17.
[13] CUI W C, YANG X X, MA M J, et al. Boosting catalytic and CO2adsorption ability by in situ Cu nanoparticle exsolution for solid oxide electrolysis cell cathode[J]. Ceram Int, 2023, 49(16):27214–27221.
[14] SUN C W, ALONSO J A, BIAN J J. Recent advances in perovskitetype oxides for energy conversion and storage applications[J]. Adv Energy Mater, 2021, 11(2):2000459.
[15] TIAN Y F, ABHISHEK N, YANG C C, et al. Progress and potential for symmetrical solid oxide electrolysis cells[J]. Matter, 2022, 5(2):482–514.
[16] SONG Y, KIM H, JANG J H, et al. Pt3Ni alloy nanoparticle electro-catalysts with unique core-shell structure on oxygen-deficient layered perovskite for solid oxide cells[J]. Adv Energy Mater, 2023,13(42):2302384.
[17] XU X M, WANG W, ZHOU W, et al. Recent advances in novel nanostructuring methods of perovskite electrocatalysts for energy-related applications[J]. Small Meth, 2018, 2(7):1800071.
[18] FU L, ZHOU J, YANG J M, et al. Exsolution of Cu nanoparticles in(LaSr)0.9Fe0.9Cu0.1O4 Ruddlesden-Popper oxide as symmetrical electrode for solid oxide cells[J]. Appl Surf Sci, 2020, 511:145525.
[19] ZHANG Z M, REN D Z, ZHANG D, et al. Electrolyte dependence for the electrochemical decarboxylation of medium-chain fatty acids(n-octanoic acid)into fuel on Pt electrode[J]. Mater Rep Energy, 2024,4(2):100244.
[20] QIAN B, WANG S, ZHENG Y F, et al. Ca-Fe Co-doped La0.75Sr0.25Cr0.5Mn0.5O3 cathodes with high electrocatalytic activity for direct CO2 electrolysis in solid oxide electrolysis cells[J]. J CO2 Util,2023, 67:102305.
[21] SUN C Z, KONG Y, SHAO L, et al. Probing oxygen vacancy effect on oxygen reduction reaction of the NdBaCo2O5+δ cathode for solid oxide fuel cells[J]. J Power Sources, 2020, 459:228017.
[22] WU H, XIAO J, ZENG X Y, et al. A high performance direct carbon solid oxide fuel cell–A green pathway for brown coal utilization[J].Appl Energy, 2019, 248:679–687.
[23] ZHANG S W, JIANG Y N, HAN H R, et al. Perovskite oxyfluoride ceramic with in situ exsolved Ni-Fe nanoparticles for direct CO2electrolysis in solid oxide electrolysis cells[J]. ACS Appl Mater Interfaces, 2022, 14(25):28854–28864.
[24] LI Y T, TIAN Y F, LI J, et al. Sr-free orthorhombic perovskite Pr0.8Ca0.2Fe0.8Co0.2O3-δ as a high-performance air electrode for reversible solid oxide cell[J]. J Power Sources, 2022, 528:231202.
[25] ZHANG W W, WANG H C, GUAN K, et al. La0.6Sr0.4Co0.2Fe0.8O3-δ/CeO2 heterostructured composite nanofibers as a highly active and robust cathode catalyst for solid oxide fuel cells[J]. ACS Appl Mater Interfaces, 2019, 11(30):26830–26841.
[26] DU Y Q, ZHAO L Y, XIAO Y Z, et al. High electrolysis performance of the SOEC cathode by creating oxygen vacancies to regulate the adsorption energy[J]. J Mater Chem A, 2024, 12(42):28911–28918.
[27] JIANG L, WEI T, HUANG Y H. Review-double-perovskite electrode design strategies and research progress for SOFCs[J]. J Electrochem Soc, 2022, 169(6).
[28] LI G D, GOU Y J, REN R Z, et al. Fluorinated Pr2NiO4+δ as high-performance air electrode for tubular reversible protonic ceramic cells[J]. J Power Sources, 2021, 508:230343.
[29] YANG C C, TIAN Y F, PU J, et al. Anion fluorine-doped La0.6Sr0.4Fe0.8Ni0.2O3-δ perovskite cathodes with enhanced electrocatalytic activity for solid oxide electrolysis cell direct CO2 electrolysis[J]. Acs Sustain Chem Eng, 2022, 10(2):1047–1058.
[30] NIU Y C, SUN C Z, SONG X Q, et al. Porous structured BaCo0.8Nb0.1Sc0.1O3-δ perovskite synthesized by template method as high performance cathode for intermediate-temperature solid oxide fuel cells[J]. J Alloys Compd, 2020, 828:154291.
[31] NIU Y C, YIN X J, SUN C Z, et al. Adjusting surface oxygen vacancies prompted perovskite as high performance cathode for solid oxide fuel cell[J]. J Alloys Compd, 2021, 865:158746.
[32] ADMASU BESHIWORK B, WAN X Y, XU M, et al. A defective iron-based perovskite cathode for high-performance IT-SOFCs:Tailoring the oxygen vacancies using Nb/Ta co-doping[J]. J Energy Chem, 2024, 88:306–316.
[33] PAN Z H, LIU Q L, ZHANG L, et al. Experimental and thermodynamic study on the performance of water electrolysis by solid oxide electrolyzer cells with Nb-doped co-based perovskite anode[J].Appl Energy, 2017, 191:559–567.
[34] HU F, LING Y H, FANG S Y, et al. Engineering dual-exsolution on self-assembled cathode to achieve efficient electrocatalytic CO2reduction[J]. Appl Catal B Environ, 2023, 337:122968.
[35] LIU T, CHEN X, WU J, et al. A highly-performed, dual-layered cathode supported solid oxide electrolysis cell for efficient CO2electrolysis fabricated by phase inversion Co-tape casting method[J]. J Elec Soc, 2017, 164(12):F1130–F1135.
[36]顾佳敏,卜云飞.可逆固体氧化物电池电极材料的研究进展[J].新能源科技, 2024(2):1–19.GU Jiamin, BU Yunfei. New Energy Sci Technol, 2024(2):1–19.
[37] ZHAO J Z, SHEN Y F, GU J M, et al. Optimizing water electrolysis activity in Mo-doped Sr2FeCoO6-δ perovskites by balancing oxygen vacancies and structural stability[J]. J Power Sources, 2024, 592:233928.
[38] ZAMUDIO-GARCíA J, CAIZáN-JUANARENA L, PORRAS-VáZQUEZ J M, et al. A review on recent advances and trends in symmetrical electrodes for solid oxide cells[J]. J Power Sources, 2022, 520:230852.
[39] ZAPATA-RAMíREZ V, MATHER G C, AZCONDO M T, et al.Electrical and electrochemical properties of the Sr(Fe, Co, Mo)O3-δsystem as air electrode for reversible solid oxide cells[J]. J Power Sources, 2019, 437:226895.
[40] ZHANG B-W, ZHU M-N, GAO M-R, et al. Fluorine-stabilized BO6octahedron of host perovskites for robust carbon dioxide electrolysis on exsolved catalysts[J]. ACS Catal, 2023, 13(20):13333–13343.
[41] ZHANG Z B, ZHU Y L, ZHONG Y J, et al. Anion doping:A new strategy for developing high-performance perovskite-type cathode materials of solid oxide fuel cells[J]. Adv Energy Mater, 2017, 7(17):1700242.
[42] ZHANG L M, YANG S Y, ZHANG S Z. A novel perovskite oxychloride as a high performance cathode for protonic ceramic fuel cells[J]. J Power Sources, 2019, 440:227125.
[43] LI Y H, LI Y, WAN Y H, et al. Perovskite oxyfluoride electrode enabling direct electrolyzing carbon dioxide with excellent electrochemical performances[J]. Adv Energy Mater, 2019, 9(3):1803156.
[44] ZHANG S W, YANG C Y, JIANG Y N, et al. A robust fluorine-containing ceramic cathode for direct CO2 electrolysis in solid oxide electrolysis cells[J]. J Energy Chem, 2023, 77:300–309.
[45] LI Y, DING R. Perovskite fluorides for electrochemical energy storage and conversion:Structure, performance and mechanisms[J]. Nano Energy, 2024, 124:109430.
[46] ZHANG L H, SUN W, XU C M, et al. Attenuating a metal–oxygen bond of a double perovskite oxide via anion doping to enhance its catalytic activity for the oxygen reduction reaction[J]. J Mater Chem A,2020, 8(28):14091–14098.
[47] BELOTTI A, WANG Y H, CURCIO A, et al. The influence of A-site deficiency on the electrochemical properties of(Ba0.95La0.05)1-xFeO3-δ as an intermediate temperature solid oxide fuel cell cathode[J]. Int J Hydrog Energy, 2022, 47(2):1229–1240.
[48] XU C M, SUN W, REN R Z, et al. A highly active and carbon-tolerant anode decorated with in situ grown cobalt nano-catalyst for intermediate-temperature solid oxide fuel cells[J]. Appl Catal B Environ, 2021, 282:119553.
[49] DANG X Y, LI T H, JIANG Y Y, et al. High-performance Ti-doped strontium cobaltite perovskites as oxygen electrodes in solid oxide cells[J]. J Power Sources, 2024, 603:234448.
[50] GUAN R, WANG Z, XU H, et al. Manipulating the activity and thermal compatibility of NdBaCoFeO5+δ cathodes for intermediatetemperature solid oxide fuel cells via fluorine doping[J]. Acs Appl Energy Mater, 2022, 5(1):481–491.
[51] ZHUANG Z C, LI Y H, YU R H, et al. Reversely trapping atoms from a perovskite surface for high-performance and durable fuel cell cathodes[J]. Nat Catal, 2022, 5(4):300–310.
[52] JIANG Y N, CHEN F L, XIA C R. A review on cathode processes and materials for electro-reduction of carbon dioxide in solid oxide electrolysis cells[J]. J Power Sources, 2021, 493:229713.
[53] LI F K, ZHANG W, ZHANG P, et al. Anion substitution strategy for constructing abundant oxygen vacancies in perovskites enables efficient nitrate electroreduction[J]. Sep Purif Technol, 2025, 357:129997.
基本信息:
DOI：10.14062/j.issn.0454-5648.20250155
中图分类号:TM911.4
引用信息:
[1]王玉齐,沈钰凡,程琳琳,等.双重缺陷调控的Sr_2FeCo_(0.7)Mo_(0.3)O_(6-δ)电极材料及其CO_2电解性能[J].硅酸盐学报,2025,53(10):2984-2994.DOI:10.14062/j.issn.0454-5648.20250155.
基金信息:
国家自然科学基金(22272081); 江苏省研究生科研与实践创新计划项目(KYCX24＿1527)
2025-10-14
2025-10-14