通过甘氨酸硝酸盐法合成出添加0~6 mol%La_2O_3-CaO的NiO-SDC(Sm0.2Ce0.8O1.9)复合阳极(La_2O_3-CaO/NiO-SDC)粉体,以SDC为电解质、BSCF(Ba0.5Sr0.5Co0.8Fe0.2O3-δ)为阴极构建SOFC单电池。考察了La_2O_3-CaO添加对Ni-SDC阳极微观组织...通过甘氨酸硝酸盐法合成出添加0~6 mol%La_2O_3-CaO的NiO-SDC(Sm0.2Ce0.8O1.9)复合阳极(La_2O_3-CaO/NiO-SDC)粉体,以SDC为电解质、BSCF(Ba0.5Sr0.5Co0.8Fe0.2O3-δ)为阴极构建SOFC单电池。考察了La_2O_3-CaO添加对Ni-SDC阳极微观组织和电化学性能等的影响;以乙醇为燃料气测定单电池的电化学性能和阳极的抗积碳性能。实验结果表明,La_2O_3-CaO/NiO-SDC复合阳极主要由NiO和SDC相组成,而La_2O_3和CaO的存在状态与其加入量有关。La_2O_3-CaO的加入,使复合阳极的电导率有所降低。添加少量La_2O_3-CaO阳极的SOFC单电池在乙醇燃料中的电池性能有所增加,800℃时添加2 mol%La_2O_3-CaO的Ni-SDC阳极的单电池最大输出功率为377.79 m W·cm-2,而Ni-SDC阳极单电池的最大输出功率仅158.86 m W·cm-2。此外,La_2O_3-CaO的添加有效减少了Ni-SDC阳极单电池在乙醇燃料中的积碳,提高了电池的运行稳定性。展开更多
The lack of thermodynamic information,such as primary phase fields and liquidus temperatures,in the CaO-SiO2-Nb2O5-La2O3 quaternary system phase diagram has restricted the comprehensive utilization of the niobium(Nb) ...The lack of thermodynamic information,such as primary phase fields and liquidus temperatures,in the CaO-SiO2-Nb2O5-La2O3 quaternary system phase diagram has restricted the comprehensive utilization of the niobium(Nb) and rare earth(RE) resources.In this work,the phase equilibria in low basicity region(w(CaO)/w(SiO2)<1) of CaO-SiO2-Nb2O5-(0-15 wt%)La2O3 system at 1373-1873 K were experimentally studied by thermodynamic equilibrium experiment,and then,the results were analyzed by X-ray diffraction(XRD),scanning electron microscopy(SEM),and energy dispersive spectrometry(EDS).Additionally,an optimized method was proposed to process the compositions of equilibrium liquid phases at different temperatures.According to the experimental results,the univariate line between CaNb2O6,SiO2 and LaNbO4 primary phase fields,interface between CaNb2O6 and SiO2 primary phase fields and isothermal liquidus surfaces in SiO2 primary phase field were determined.Finally,the spatial phase diagram of CaO-SiO2-Nb2O5-La2O3 within specific region was constructed,and furthermore,the phase diagram was also presented in CaO-SiO2-Nb2O5 pseudo-ternary system with w(La2O3)=5 wt%,10 wt% and 15 wt%.The research results have guiding significance for the improvement of related phase diagram and the comprehensive utilization of Nb and RE resources.展开更多
文摘通过甘氨酸硝酸盐法合成出添加0~6 mol%La_2O_3-CaO的NiO-SDC(Sm0.2Ce0.8O1.9)复合阳极(La_2O_3-CaO/NiO-SDC)粉体,以SDC为电解质、BSCF(Ba0.5Sr0.5Co0.8Fe0.2O3-δ)为阴极构建SOFC单电池。考察了La_2O_3-CaO添加对Ni-SDC阳极微观组织和电化学性能等的影响;以乙醇为燃料气测定单电池的电化学性能和阳极的抗积碳性能。实验结果表明,La_2O_3-CaO/NiO-SDC复合阳极主要由NiO和SDC相组成,而La_2O_3和CaO的存在状态与其加入量有关。La_2O_3-CaO的加入,使复合阳极的电导率有所降低。添加少量La_2O_3-CaO阳极的SOFC单电池在乙醇燃料中的电池性能有所增加,800℃时添加2 mol%La_2O_3-CaO的Ni-SDC阳极的单电池最大输出功率为377.79 m W·cm-2,而Ni-SDC阳极单电池的最大输出功率仅158.86 m W·cm-2。此外,La_2O_3-CaO的添加有效减少了Ni-SDC阳极单电池在乙醇燃料中的积碳,提高了电池的运行稳定性。
基金Project supported by the National Key R&D Program of China(2017YFC0805100)the National Natural Science Foundation of China(51774087)the Fundamental Research Funds for the Central Universities China(N162506002)
文摘The lack of thermodynamic information,such as primary phase fields and liquidus temperatures,in the CaO-SiO2-Nb2O5-La2O3 quaternary system phase diagram has restricted the comprehensive utilization of the niobium(Nb) and rare earth(RE) resources.In this work,the phase equilibria in low basicity region(w(CaO)/w(SiO2)<1) of CaO-SiO2-Nb2O5-(0-15 wt%)La2O3 system at 1373-1873 K were experimentally studied by thermodynamic equilibrium experiment,and then,the results were analyzed by X-ray diffraction(XRD),scanning electron microscopy(SEM),and energy dispersive spectrometry(EDS).Additionally,an optimized method was proposed to process the compositions of equilibrium liquid phases at different temperatures.According to the experimental results,the univariate line between CaNb2O6,SiO2 and LaNbO4 primary phase fields,interface between CaNb2O6 and SiO2 primary phase fields and isothermal liquidus surfaces in SiO2 primary phase field were determined.Finally,the spatial phase diagram of CaO-SiO2-Nb2O5-La2O3 within specific region was constructed,and furthermore,the phase diagram was also presented in CaO-SiO2-Nb2O5 pseudo-ternary system with w(La2O3)=5 wt%,10 wt% and 15 wt%.The research results have guiding significance for the improvement of related phase diagram and the comprehensive utilization of Nb and RE resources.
