Performance degradation shortens the life of solid oxide fuel cells in practical applications.Revealing the degradation mechanism is crucial for the continuous improvement of cell durability.In this work,the effects o...Performance degradation shortens the life of solid oxide fuel cells in practical applications.Revealing the degradation mechanism is crucial for the continuous improvement of cell durability.In this work,the effects of cell operating conditions on the terminal voltage and anode microstructure of a Ni-yttria-stabilized zirconia anode-supported single cell were investigated.The microstructure of the anode active area near the electrolyte was characterized by laser optical microscopy and focused ion beam-scanning electron microscopy.Ni depletion at the anode/electrolyte interface region was observed after 100 h discharge tests.In addition,the long-term stability of the single cell was evaluated at 700℃for 3000 h.After an initial decline,the anode-supported single cell exhibits good durability with a voltage decay rate of 0.72%/kh and an electrode polarization resistance decay rate of 0.17%/kh.The main performance loss of the cell originates from the initial degradation.展开更多
Accurate prediction of performance degradation in complex systems such as solid oxide fuel cells is crucial for expediting technological advancements.However,significant challenges still persist due to limited compreh...Accurate prediction of performance degradation in complex systems such as solid oxide fuel cells is crucial for expediting technological advancements.However,significant challenges still persist due to limited comprehension of degradation mechanisms and difficulties in acquiring in-situ features.In this study,we propose an effective approach that integrates long short-term memory(LSTM) neural network and dynamic electrochemical impedance spectroscopy(DEIS).This integrated approach enables precise prediction of future evolutions in both current-voltage and EIS features using historical testing data,without prior knowledge of degradation mechanisms.For short-term predictions spanning hundreds of hours,our approach achieves a prediction accuracy exceeding 0.99,showcasing promising prospects for diagnostic applications.Additionally,for long-term predictions spanning thousands of hours,we quantitatively determine the significance of each degradation mechanism,which is crucial for enhancing cell durability.Moreover,our proposed approach demonstrates satisfactory predictive ability in both time and frequency domains,offering the potential to reduce EIS testing time by more than half.展开更多
The authors proposed an integrated gasification fuel cell zero-emission system.The coal char gasification is discussed using high temperature and concentration of CO_(2) produced by solid oxide fuel cells and oxy-fuel...The authors proposed an integrated gasification fuel cell zero-emission system.The coal char gasification is discussed using high temperature and concentration of CO_(2) produced by solid oxide fuel cells and oxy-fuel combustion.The gasification is simulated by Aspen plus based on Gibbs free energy minimization method.Gasification model of pulverized coal char is computed and analyzed.Effects of gas flow rate,pressure,preheating temperature,heat losses on syngas composition,reaction temperature,lower heating value and carbon conversion are studied.Results and parameters are determined as following.The optimum O_(2) flow rate is 20 kg/h.The reaction temperature decreases from 1645 to 1329℃when the CO_(2)flow rate increases from 0 to 5 kg/h,the CO_(2) flow rate should be operated reasonably;lower heating value reduces and reaction temperature increases as the pressure increases;compared to the CO_(2) preheating,O_(2) preheating has greater influence on reaction temperature and lower heating value.展开更多
Porous Sr-doped lanthanum manganite–yttria stabilized zirconia(LSM–YSZ)oxygen electrode is prepared by an infiltration process for a reversible solid oxide fuel cell(RSOFC).X-ray diffraction and SEM analysis display...Porous Sr-doped lanthanum manganite–yttria stabilized zirconia(LSM–YSZ)oxygen electrode is prepared by an infiltration process for a reversible solid oxide fuel cell(RSOFC).X-ray diffraction and SEM analysis display that perovskite phase LSM submicro particles are evenly distributed in the porous YSZ matrix.Polarization curves and electrochemical impedance spectra are conducted for the RSOFC at 800 and 850C under both SOFC and SOEC modes.At 850℃,the single cell has the maximum power density of~726 mW/cm^(2)under SOFC mode,and electrolysis voltage of 1.35 V at 1 A/cm^(2)under SOEC mode.Fuel cell/water electrolysis cycle shows the cell has good performance stability during 6 cycles,which exhibits the LSM–YSZ oxygen electrode has high electrochemical performance and good stability.The results suggest that netw ork-like LSM–YSZ electrode made by infiltration process could be a promising oxygen electrode for high temperature RSOFCs.展开更多
Solid oxide fuel cell combined with heat and power(SOFC-CHP)system is a distributed power generation system with low pollution and high efficiency.In this paper,a 10 kW SOFC-CHP system model using syngas was built in ...Solid oxide fuel cell combined with heat and power(SOFC-CHP)system is a distributed power generation system with low pollution and high efficiency.In this paper,a 10 kW SOFC-CHP system model using syngas was built in Aspen plus.Key operating parameters,such as steam to fuel ratio,stack temperature,reformer temperature,air flow rate,and air preheating temperature,were analyzed.Optimization was conducted based on the simulation results.Results suggest that higher steam to fuel ratio is beneficial to the electrical efficiency,but it might decrease the gross system efficiency.Higher stack and reformer temperatures contribute to the electrical efficiency,and the optimal operating temperatures of stack and reformer when considering the stack degradation are 750℃and 700℃,respectively.The air preheating temperature barely affects the electrical efficiency but affects the thermal efficiency and the gross system efficiency,the recommended value is around 600℃under the reference condition.展开更多
The hydrogen fuel cell vehicle is rapidly developing in China for carbon reduction and neutrality.This paper evaluated the life-cycle cost and carbon emission of hydrogen energy via lots of field surveys,including hyd...The hydrogen fuel cell vehicle is rapidly developing in China for carbon reduction and neutrality.This paper evaluated the life-cycle cost and carbon emission of hydrogen energy via lots of field surveys,including hydrogen production and packing in chlor-alkali plants,transport by tube trailers,storage and refueling in hydrogen refueling stations(HRSs),and application for use in two different cities.It also conducted a comparative study for battery electric vehicles(BEVs)and internal combustion engine vehicles(ICEVs).The result indicates that hydrogen fuel cell vehicle(FCV)has the best environmental performance but the highest energy cost.However,a sufficient hydrogen supply can significantly reduce the carbon intensity and FCV energy cost of the current system.The carbon emission for FCV application has the potential to decrease by 73.1%in City A and 43.8%in City B.It only takes 11.0%–20.1%of the BEV emission and 8.2%–9.8%of the ICEV emission.The cost of FCV driving can be reduced by 39.1%in City A.Further improvement can be obtained with an economical and“greener”hydrogen production pathway.展开更多
Carbon deposition is a primary concern during the operation of solid oxide fuel cells（SOFCs） fueled with hydrocarbon fuels, leading to cell degradation and even cell damage. Carbon elimination is expected to be a pr...Carbon deposition is a primary concern during the operation of solid oxide fuel cells（SOFCs） fueled with hydrocarbon fuels, leading to cell degradation and even cell damage. Carbon elimination is expected to be a promising approach to prolong cell life. This work reports on a combined experimental and theoretical investigation of cell regeneration from anode carbon deposition of tubular SOFCs fabricated by phase-inversion and co-sintering techniques. The as-prepared cell exhibits a maximum power density of 0.20 W cm;at 800 ℃ fueling with wet CH;, but fails to stable operation due to severe carbon deposition.Based on thermodynamic predictions, a successive cell-protecting regeneration process is proposed to eliminate deposited carbon without oxidizing Ni catalysts, during which CH;and H;fuels are provided in circulation. Through a total of 35 cycling tests, cell performance can always successfully restore to the initial level.The possible carbon elimination mechanism is investigated in detail based on thermodynamic and first-principle calculations. The feasibility of carbon elimination using in situ produced oxygen or steam through electrochemical reaction has been revealed, providing a novel continuous operation mode for hydrocarbon-based SOFCs.展开更多
In this work, a dual-phase material consisting Gd0.1Ce0.9O2-δ （GDC, 60 wt%） was synthesized. of La0.7Ca0.3Cr0.95Zn0.05O3-δ （LCCZ, 40 wt%） and Properties including phase structure, sintering behavior, electrical ...In this work, a dual-phase material consisting Gd0.1Ce0.9O2-δ （GDC, 60 wt%） was synthesized. of La0.7Ca0.3Cr0.95Zn0.05O3-δ （LCCZ, 40 wt%） and Properties including phase structure, sintering behavior, electrical conductivity and oxygen permeability for LCCZ-GDC were evaluated. The results show that dense LCCZ-GDC dual-phase disks were obtained at the sintering temperature of 1250, 1300, 1350 and 1400 ℃ by tape casting and high temperature sintering method. The grain sizes of both GDC and LCCZ grew up with the increasing of sintering temperature. The average grain size of GDC was about 0.5, 0.8, 1.4, 1.8 μm while the average grain size of LCCZ was about 0.8, 1.5, 1.8 and 2 pm after sintering at 1250, 1300, 1350 and 1400℃, respectively. Oxygen flux of LCCZ-GDC decreased with the increase of sintering temperature from 1250 to 1400 ℃. The oxygen flux of LCCZ-GDC sintered at 1250 ℃ reached 0.079 mL/min/cm2 at 975℃ with a membrane thickness of 800 μm. Dual-phase material of LCCZ-GDC will be a promising oxygen transport membrane material for its low sintering temperature and good microstructure.展开更多
In this work, a multi-layer anode supported solid oxide fuel cell(SOFC) is designed and successfully prepared through sequential tape casting and co-firing. The single cell is consisted of NiO-3 YSZ(3 YSZ: 3 mol.% ytt...In this work, a multi-layer anode supported solid oxide fuel cell(SOFC) is designed and successfully prepared through sequential tape casting and co-firing. The single cell is consisted of NiO-3 YSZ(3 YSZ: 3 mol.% yttria doped zirconia) anode support, NiO-8 YSZ(8 YSZ: 8 mol.% yttria stabilized zirconia) anode functional layer, dense 8 YSZ electrolyte layer, and porous 3 YSZ cathode scaffold layer with infiltrated La_(0.6)Sr_(0.4)Co_(0.2)Fe_(0.8)O_(3-δ) cathode. The clear interfaces and good contacts between each layer, without element inter-diffusion being observed, suggest that this sequential tape casting and co-firing is a feasible and successful route for anode supported single cell fabrication. This cell exhibits remarkable high open circuit voltage of 1.097 V at 800?C under room temperature humidified hydrogen, with highly dense and gastight electrolyte layer. It provides a power density of 360 mW/cm^2 under operation voltage of0.75 V at 800?C and a stable operation of ～110 h at 750?C under current density of-300 mA/cm^2. Furthermore, this cell also presents encouraging electrochemical responses under various anode hydrogen partial pressures and maintains high power output at low fuel concentrations.展开更多
Energy is important for human survival and development.In September 2020,the Chinese government announced that“China aims to have their CO_(2) emissions peak before 2030 and achieve carbon neutrality before 2060.”As...Energy is important for human survival and development.In September 2020,the Chinese government announced that“China aims to have their CO_(2) emissions peak before 2030 and achieve carbon neutrality before 2060.”As China’s reformation and opening-up proceeds into its fifth decade,this new vision for its future is in line with that of the world’s major economies in terms of the need to reach net zero emissions globally by the mid-21stcentury[1].However,coal-fueled thermal power generation is currently dominant and accounts for more than 70%of the total amount of power generated in China,making it the world’s largest energy consumer and carbon emitter.Based on the country’s domestic resources,namely the abundance of coal and scarcity of oil and gas,it would be difficult to fundamentally change this coal-based energy structure in the short term.In 2021,the global total energy sector was responsible for 36.3 Gt of CO_(2) emissions,including approximately 12 Gt from China,which thus accounts for one-third of the total global emissions[2].The demand for efficiency,energy savings,and emissions reduction in the power generation industry has become increasingly prominent.The need has arisen to enhance ways in which to use coal cleanly and efficiently,reduce the consumption thereof,and replace coal with other forms of energy.In addition,carbon emissions need to be lowered by promoting the adoption of alternative power generation technologies that are more energy efficient.This would require transformation away from coal power and the exploration of clean,efficient,flexible,and safe forms of energy as the main future development directions[3].展开更多
In this work, a tubular ceramic-supported solid oxide fuel cell （SOFC） was successfully fabricated by a low cost and simple process involving phase-inversion, brush coating and co-sintering. Properties in- cluding s...In this work, a tubular ceramic-supported solid oxide fuel cell （SOFC） was successfully fabricated by a low cost and simple process involving phase-inversion, brush coating and co-sintering. Properties in- cluding sintering behavior, microstructure of the tubular support as well as the electrochemical properties of single cell were investigated. The results show that a porous tubular support with finger-like pores and macrovoids was obtained after phase-inversion process. The tubular support is proved to be gaspermeable after sintering at 1400 ℃ with shrinkage of about 34%. The maximum power density of single tubular SOFC is 100 mW/cm2 and 122 mW/cm2 at 850 ℃ when fed with wet methane and hydrogen, respectively. The current collection, thickness of electrolyte and gas permeability of tubular support should account for the large total resistance. The present tubular design could be expected to deliver a higher voltage for longer support with several segmented-in-series cell stacks.展开更多
La（0.4）Sr（0.6）Co（0.2）Fe（0.7）Nb（0.1）O（3-δ）（LSCFN）was applied as both anode and cathode for symmetrical solid oxide fuel cells（SSOFCs）with zirconia based electrolyte.The cell with LSCFN electrode was fa...La（0.4）Sr（0.6）Co（0.2）Fe（0.7）Nb（0.1）O（3-δ）（LSCFN）was applied as both anode and cathode for symmetrical solid oxide fuel cells（SSOFCs）with zirconia based electrolyte.The cell with LSCFN electrode was fabricated by tape-casting and screen printing.Fabrication process was optimized firstly by comparing co-sintering and separate-sintering of electrode and electrolyte.To further improve the LSCFN electrode properties,oxygen ionic conductor of Gd（0.1）Ce（0.9）O（2-δ）（GDC）was added into the LSCFN electrode.The preferred composition of LSCFN-GDC composite electrode was found to be 1：1 in weight ratio with polarization resistance of 0.16Ωcm^2at 800~℃.The maximum power densities of LSCFN-GDC｜｜GDC/YSZ/GDC｜｜LSCFN-GDC tested in H2and CH4with 3%H2O were 395 m W cm^（-2）and 124 m W cm^（-2）at 850~？C,respectively,which were much higher than that of LSCFN｜｜GDC/YSZ/GDC｜｜LSCFN cells at same condition,possibly due to the extension of the triple phase boundary induced by the addition of GDC.The cell showed reasonable stability using H2and CH4with 3%H2O as fuels and no significant power output degradation was observed after total 200 h operation.展开更多
Gadolinium-doped ceria(GDC)interlayers are required to prevent the interfacial reaction between La_(0.6)Sr_(0.4)Co_(0.2)Fe_(0.8)O_(3)(LSCF)cathode and Y_(2)O_(3)-stabilized ZrO 2(YSZ)electrolyte in solid oxide fuel ce...Gadolinium-doped ceria(GDC)interlayers are required to prevent the interfacial reaction between La_(0.6)Sr_(0.4)Co_(0.2)Fe_(0.8)O_(3)(LSCF)cathode and Y_(2)O_(3)-stabilized ZrO 2(YSZ)electrolyte in solid oxide fuel cells(SOFCs).However,it's difficult to prepare a thin and dense GDC interlayer on the sintered half-cell at a low temperature.In this study,the physical vapor deposition(PVD)method was employed to success-fully manufacture dense GDC interlayers with the thickness of 1 m m.The influences of GDC sintering temperature(900℃,1000℃ and 1100℃)on cell performance characteristics and degradation behavior were investigated.The cell with GDC interlayer sintered at 1100?C showed the lowest degradation rate during the 216-h operation.The best stability was attributed to the most effective inhibition of Sr diffusion by the GDC interlayer,which was demonstrated by the almost unchanged Ohmic and polari-zation resistances during the aging stage and the negligible Sr enrichment at YSZ/GDC interface.Compared to the conventional screen-printed GDC interlayers(sintered above 1250℃),the GDC inter-layer prepared by the PVD method and sintered at 1100℃ was significantly denser and thinner,showing a promising application prospect due to its benefits for cell stability.展开更多
基金supported by the National Key R&D Program of China(No.2018YFB1502202)the Fundamental Research Funds for the Central Universities(No.FRF-GF-20-09B).
文摘Performance degradation shortens the life of solid oxide fuel cells in practical applications.Revealing the degradation mechanism is crucial for the continuous improvement of cell durability.In this work,the effects of cell operating conditions on the terminal voltage and anode microstructure of a Ni-yttria-stabilized zirconia anode-supported single cell were investigated.The microstructure of the anode active area near the electrolyte was characterized by laser optical microscopy and focused ion beam-scanning electron microscopy.Ni depletion at the anode/electrolyte interface region was observed after 100 h discharge tests.In addition,the long-term stability of the single cell was evaluated at 700℃for 3000 h.After an initial decline,the anode-supported single cell exhibits good durability with a voltage decay rate of 0.72%/kh and an electrode polarization resistance decay rate of 0.17%/kh.The main performance loss of the cell originates from the initial degradation.
基金partly supported by Japan Society for the Promotion of Science (JSPS) Postdoctoral Fellowships for Research in Japan (P22370)by Key Project of Jiangsu Province (BE2022029) in China。
文摘Accurate prediction of performance degradation in complex systems such as solid oxide fuel cells is crucial for expediting technological advancements.However,significant challenges still persist due to limited comprehension of degradation mechanisms and difficulties in acquiring in-situ features.In this study,we propose an effective approach that integrates long short-term memory(LSTM) neural network and dynamic electrochemical impedance spectroscopy(DEIS).This integrated approach enables precise prediction of future evolutions in both current-voltage and EIS features using historical testing data,without prior knowledge of degradation mechanisms.For short-term predictions spanning hundreds of hours,our approach achieves a prediction accuracy exceeding 0.99,showcasing promising prospects for diagnostic applications.Additionally,for long-term predictions spanning thousands of hours,we quantitatively determine the significance of each degradation mechanism,which is crucial for enhancing cell durability.Moreover,our proposed approach demonstrates satisfactory predictive ability in both time and frequency domains,offering the potential to reduce EIS testing time by more than half.
基金National Basic Research Program of China(No.2012CB215404,2012CB215406)the National Natural Science Foundation of China(No.51261120378)for financial support of this work.
文摘The authors proposed an integrated gasification fuel cell zero-emission system.The coal char gasification is discussed using high temperature and concentration of CO_(2) produced by solid oxide fuel cells and oxy-fuel combustion.The gasification is simulated by Aspen plus based on Gibbs free energy minimization method.Gasification model of pulverized coal char is computed and analyzed.Effects of gas flow rate,pressure,preheating temperature,heat losses on syngas composition,reaction temperature,lower heating value and carbon conversion are studied.Results and parameters are determined as following.The optimum O_(2) flow rate is 20 kg/h.The reaction temperature decreases from 1645 to 1329℃when the CO_(2)flow rate increases from 0 to 5 kg/h,the CO_(2) flow rate should be operated reasonably;lower heating value reduces and reaction temperature increases as the pressure increases;compared to the CO_(2) preheating,O_(2) preheating has greater influence on reaction temperature and lower heating value.
基金This project was sponsored by financial supports from the Major State Basic Research Development Program of China(973 Program,No.2012CB215406).
文摘Porous Sr-doped lanthanum manganite–yttria stabilized zirconia(LSM–YSZ)oxygen electrode is prepared by an infiltration process for a reversible solid oxide fuel cell(RSOFC).X-ray diffraction and SEM analysis display that perovskite phase LSM submicro particles are evenly distributed in the porous YSZ matrix.Polarization curves and electrochemical impedance spectra are conducted for the RSOFC at 800 and 850C under both SOFC and SOEC modes.At 850℃,the single cell has the maximum power density of~726 mW/cm^(2)under SOFC mode,and electrolysis voltage of 1.35 V at 1 A/cm^(2)under SOEC mode.Fuel cell/water electrolysis cycle shows the cell has good performance stability during 6 cycles,which exhibits the LSM–YSZ oxygen electrode has high electrochemical performance and good stability.The results suggest that netw ork-like LSM–YSZ electrode made by infiltration process could be a promising oxygen electrode for high temperature RSOFCs.
基金the National Key R&D Program of China(2017YFB0601903).
文摘Solid oxide fuel cell combined with heat and power(SOFC-CHP)system is a distributed power generation system with low pollution and high efficiency.In this paper,a 10 kW SOFC-CHP system model using syngas was built in Aspen plus.Key operating parameters,such as steam to fuel ratio,stack temperature,reformer temperature,air flow rate,and air preheating temperature,were analyzed.Optimization was conducted based on the simulation results.Results suggest that higher steam to fuel ratio is beneficial to the electrical efficiency,but it might decrease the gross system efficiency.Higher stack and reformer temperatures contribute to the electrical efficiency,and the optimal operating temperatures of stack and reformer when considering the stack degradation are 750℃and 700℃,respectively.The air preheating temperature barely affects the electrical efficiency but affects the thermal efficiency and the gross system efficiency,the recommended value is around 600℃under the reference condition.
基金supported by the Consulting Research Project of the Chinese Academy of Engineering(Grant No.2019-XZ-51).
文摘The hydrogen fuel cell vehicle is rapidly developing in China for carbon reduction and neutrality.This paper evaluated the life-cycle cost and carbon emission of hydrogen energy via lots of field surveys,including hydrogen production and packing in chlor-alkali plants,transport by tube trailers,storage and refueling in hydrogen refueling stations(HRSs),and application for use in two different cities.It also conducted a comparative study for battery electric vehicles(BEVs)and internal combustion engine vehicles(ICEVs).The result indicates that hydrogen fuel cell vehicle(FCV)has the best environmental performance but the highest energy cost.However,a sufficient hydrogen supply can significantly reduce the carbon intensity and FCV energy cost of the current system.The carbon emission for FCV application has the potential to decrease by 73.1%in City A and 43.8%in City B.It only takes 11.0%–20.1%of the BEV emission and 8.2%–9.8%of the ICEV emission.The cost of FCV driving can be reduced by 39.1%in City A.Further improvement can be obtained with an economical and“greener”hydrogen production pathway.
基金supported by the National Natural Science Foundation of China(51976138)the grant(Project Number:N_PolyU552/20)from Research Grant Council,University Grants Committee,Hong Kong SARProject of Strategic Importance Program of The Hong Kong Polytechnic University(P0035168).
基金supported financially by the Ministry of Science and Technology,China(No.MOST 2017YFB0601901 and 2017YFB0601903)Dongguan Science and Technology Bureau,Guangdong Project(No.201460720100025)Tsinghua University Initiative Scientific Research Program(No.2015THZ0)
文摘Carbon deposition is a primary concern during the operation of solid oxide fuel cells（SOFCs） fueled with hydrocarbon fuels, leading to cell degradation and even cell damage. Carbon elimination is expected to be a promising approach to prolong cell life. This work reports on a combined experimental and theoretical investigation of cell regeneration from anode carbon deposition of tubular SOFCs fabricated by phase-inversion and co-sintering techniques. The as-prepared cell exhibits a maximum power density of 0.20 W cm;at 800 ℃ fueling with wet CH;, but fails to stable operation due to severe carbon deposition.Based on thermodynamic predictions, a successive cell-protecting regeneration process is proposed to eliminate deposited carbon without oxidizing Ni catalysts, during which CH;and H;fuels are provided in circulation. Through a total of 35 cycling tests, cell performance can always successfully restore to the initial level.The possible carbon elimination mechanism is investigated in detail based on thermodynamic and first-principle calculations. The feasibility of carbon elimination using in situ produced oxygen or steam through electrochemical reaction has been revealed, providing a novel continuous operation mode for hydrocarbon-based SOFCs.
基金the financial support from the National Basic Research Program of China("973 Program",No. 2012CB215404)the National Natural Science Foundation of China(No.51261120378)the State Key Laboratory of Coal Resources and Safe Mining(No.2013CRSMZZ01)
文摘In this work, a dual-phase material consisting Gd0.1Ce0.9O2-δ （GDC, 60 wt%） was synthesized. of La0.7Ca0.3Cr0.95Zn0.05O3-δ （LCCZ, 40 wt%） and Properties including phase structure, sintering behavior, electrical conductivity and oxygen permeability for LCCZ-GDC were evaluated. The results show that dense LCCZ-GDC dual-phase disks were obtained at the sintering temperature of 1250, 1300, 1350 and 1400 ℃ by tape casting and high temperature sintering method. The grain sizes of both GDC and LCCZ grew up with the increasing of sintering temperature. The average grain size of GDC was about 0.5, 0.8, 1.4, 1.8 μm while the average grain size of LCCZ was about 0.8, 1.5, 1.8 and 2 pm after sintering at 1250, 1300, 1350 and 1400℃, respectively. Oxygen flux of LCCZ-GDC decreased with the increase of sintering temperature from 1250 to 1400 ℃. The oxygen flux of LCCZ-GDC sintered at 1250 ℃ reached 0.079 mL/min/cm2 at 975℃ with a membrane thickness of 800 μm. Dual-phase material of LCCZ-GDC will be a promising oxygen transport membrane material for its low sintering temperature and good microstructure.
基金supported financially by the Key R & D Program of Jiangsu Province (No.BE2017098)the Natural Science Foundation of Jiangsu Province (No.BK20170847)+1 种基金the Top-notch Academic Programs Project of Jiangsu Higher Education Institutionsthe Start-Up Fund of Nanjing University of Science and Technology
文摘In this work, a multi-layer anode supported solid oxide fuel cell(SOFC) is designed and successfully prepared through sequential tape casting and co-firing. The single cell is consisted of NiO-3 YSZ(3 YSZ: 3 mol.% yttria doped zirconia) anode support, NiO-8 YSZ(8 YSZ: 8 mol.% yttria stabilized zirconia) anode functional layer, dense 8 YSZ electrolyte layer, and porous 3 YSZ cathode scaffold layer with infiltrated La_(0.6)Sr_(0.4)Co_(0.2)Fe_(0.8)O_(3-δ) cathode. The clear interfaces and good contacts between each layer, without element inter-diffusion being observed, suggest that this sequential tape casting and co-firing is a feasible and successful route for anode supported single cell fabrication. This cell exhibits remarkable high open circuit voltage of 1.097 V at 800?C under room temperature humidified hydrogen, with highly dense and gastight electrolyte layer. It provides a power density of 360 mW/cm^2 under operation voltage of0.75 V at 800?C and a stable operation of ～110 h at 750?C under current density of-300 mA/cm^2. Furthermore, this cell also presents encouraging electrochemical responses under various anode hydrogen partial pressures and maintains high power output at low fuel concentrations.
文摘Energy is important for human survival and development.In September 2020,the Chinese government announced that“China aims to have their CO_(2) emissions peak before 2030 and achieve carbon neutrality before 2060.”As China’s reformation and opening-up proceeds into its fifth decade,this new vision for its future is in line with that of the world’s major economies in terms of the need to reach net zero emissions globally by the mid-21stcentury[1].However,coal-fueled thermal power generation is currently dominant and accounts for more than 70%of the total amount of power generated in China,making it the world’s largest energy consumer and carbon emitter.Based on the country’s domestic resources,namely the abundance of coal and scarcity of oil and gas,it would be difficult to fundamentally change this coal-based energy structure in the short term.In 2021,the global total energy sector was responsible for 36.3 Gt of CO_(2) emissions,including approximately 12 Gt from China,which thus accounts for one-third of the total global emissions[2].The demand for efficiency,energy savings,and emissions reduction in the power generation industry has become increasingly prominent.The need has arisen to enhance ways in which to use coal cleanly and efficiently,reduce the consumption thereof,and replace coal with other forms of energy.In addition,carbon emissions need to be lowered by promoting the adoption of alternative power generation technologies that are more energy efficient.This would require transformation away from coal power and the exploration of clean,efficient,flexible,and safe forms of energy as the main future development directions[3].
基金?nancial support from the National Basic Research Program of China(973 Program,No.2012CB215404)the National Natural Science Foundation of China(Nos.51261120378 and 51402355)+1 种基金Beijing Natural Science Foundation(No.2154056)Specialized Research Fund for the Doctoral Program of Higher Education(SRFDP,No.20130023120023)
文摘In this work, a tubular ceramic-supported solid oxide fuel cell （SOFC） was successfully fabricated by a low cost and simple process involving phase-inversion, brush coating and co-sintering. Properties in- cluding sintering behavior, microstructure of the tubular support as well as the electrochemical properties of single cell were investigated. The results show that a porous tubular support with finger-like pores and macrovoids was obtained after phase-inversion process. The tubular support is proved to be gaspermeable after sintering at 1400 ℃ with shrinkage of about 34%. The maximum power density of single tubular SOFC is 100 mW/cm2 and 122 mW/cm2 at 850 ℃ when fed with wet methane and hydrogen, respectively. The current collection, thickness of electrolyte and gas permeability of tubular support should account for the large total resistance. The present tubular design could be expected to deliver a higher voltage for longer support with several segmented-in-series cell stacks.
基金supported by the National Natural Science Foundation of China (No. 51402355)Natural Science Foundation of Beijing Project (Nos. LJ201531 and 2154056)+1 种基金Shanxi Province Project (No. MD2014-08)Guangdong Project (No. 201460720100025)
文摘La（0.4）Sr（0.6）Co（0.2）Fe（0.7）Nb（0.1）O（3-δ）（LSCFN）was applied as both anode and cathode for symmetrical solid oxide fuel cells（SSOFCs）with zirconia based electrolyte.The cell with LSCFN electrode was fabricated by tape-casting and screen printing.Fabrication process was optimized firstly by comparing co-sintering and separate-sintering of electrode and electrolyte.To further improve the LSCFN electrode properties,oxygen ionic conductor of Gd（0.1）Ce（0.9）O（2-δ）（GDC）was added into the LSCFN electrode.The preferred composition of LSCFN-GDC composite electrode was found to be 1：1 in weight ratio with polarization resistance of 0.16Ωcm^2at 800~℃.The maximum power densities of LSCFN-GDC｜｜GDC/YSZ/GDC｜｜LSCFN-GDC tested in H2and CH4with 3%H2O were 395 m W cm^（-2）and 124 m W cm^（-2）at 850~？C,respectively,which were much higher than that of LSCFN｜｜GDC/YSZ/GDC｜｜LSCFN cells at same condition,possibly due to the extension of the triple phase boundary induced by the addition of GDC.The cell showed reasonable stability using H2and CH4with 3%H2O as fuels and no significant power output degradation was observed after total 200 h operation.
基金This work was supported by the National Key R&D Program of China(2018YFB1502202)Tsinghua University Initiative Scien-tific Research Program(20193080038).
文摘Gadolinium-doped ceria(GDC)interlayers are required to prevent the interfacial reaction between La_(0.6)Sr_(0.4)Co_(0.2)Fe_(0.8)O_(3)(LSCF)cathode and Y_(2)O_(3)-stabilized ZrO 2(YSZ)electrolyte in solid oxide fuel cells(SOFCs).However,it's difficult to prepare a thin and dense GDC interlayer on the sintered half-cell at a low temperature.In this study,the physical vapor deposition(PVD)method was employed to success-fully manufacture dense GDC interlayers with the thickness of 1 m m.The influences of GDC sintering temperature(900℃,1000℃ and 1100℃)on cell performance characteristics and degradation behavior were investigated.The cell with GDC interlayer sintered at 1100?C showed the lowest degradation rate during the 216-h operation.The best stability was attributed to the most effective inhibition of Sr diffusion by the GDC interlayer,which was demonstrated by the almost unchanged Ohmic and polari-zation resistances during the aging stage and the negligible Sr enrichment at YSZ/GDC interface.Compared to the conventional screen-printed GDC interlayers(sintered above 1250℃),the GDC inter-layer prepared by the PVD method and sintered at 1100℃ was significantly denser and thinner,showing a promising application prospect due to its benefits for cell stability.
