Apatite-lanthanum silicate has attracted considerable interest in recent years due to its high oxide ion conductivity.In this paper,V-doped samples La10-xVx(SiO4) 6O3+x(0≤x≤1.5) were prepared by sol-gel method and t...Apatite-lanthanum silicate has attracted considerable interest in recent years due to its high oxide ion conductivity.In this paper,V-doped samples La10-xVx(SiO4) 6O3+x(0≤x≤1.5) were prepared by sol-gel method and the influences of V-dopant content on calcining temperature and conductivity were reported.The samples were characterized by thermal analysis(TG-DSC) ,X-ray diffraction(XRD) and scanning electron micrograph(SEM) . The apatite was obtained at 800°C,a relatively low temperature in comparison to 1500°C with the conventional solid-state method.The ceramic pellets sintered at 1200°C for 5 h showed a higher relative density than La9.33Si6O26 pellets sintered at 1400°C for 20 h.The conductivities of samples were measured by electrochemical impedance spectroscopy.The conductivity was improved with the increase of V-dopant content on La site.展开更多
Rare-earth elements(REs)based oxide ion conductors show promising performance and potential applications in solid oxide fuel cells(SOFCs).To meet the requirements of intermediate-temperature(IT)SOFCs operating in the ...Rare-earth elements(REs)based oxide ion conductors show promising performance and potential applications in solid oxide fuel cells(SOFCs).To meet the requirements of intermediate-temperature(IT)SOFCs operating in the range of 600–800℃,oxide ion conductors with various structures were developed and summarized here,namely,pure oxide ion conductors and mixed oxide ionic and electronic conductors(MIECs).For the former,their structures range from traditional structure types(perovskite,fluorite,etc.)to new structures with isolated polyhedral units.For MIECs,perovskite and related structures have dominated this field due to their high oxide ion and electronic conductivities.Among these oxide ion conductors,REs play a crucial role in the modification of the structure and performances due to their unique characters,such as lanthanide contraction effect and stable valence(+3).This review emphasizes the structure–performance relationships among the REs.Furthermore,challenges particularly towards obtaining high oxide ion conductivity at low temperatures for lowering the operating temperature and thereby enhancing the device performance,and future prospects of RE-based oxide ion conductors are also discussed,together with advanced research techniques and new research directions being the possible strategies to overcome these challenges.展开更多
基金Supported by the Joint Funds of NSFC-Guangdong of China(U0834004)the Natural Science Foundation of Guangdong Province(06025657)
文摘Apatite-lanthanum silicate has attracted considerable interest in recent years due to its high oxide ion conductivity.In this paper,V-doped samples La10-xVx(SiO4) 6O3+x(0≤x≤1.5) were prepared by sol-gel method and the influences of V-dopant content on calcining temperature and conductivity were reported.The samples were characterized by thermal analysis(TG-DSC) ,X-ray diffraction(XRD) and scanning electron micrograph(SEM) . The apatite was obtained at 800°C,a relatively low temperature in comparison to 1500°C with the conventional solid-state method.The ceramic pellets sintered at 1200°C for 5 h showed a higher relative density than La9.33Si6O26 pellets sintered at 1400°C for 20 h.The conductivities of samples were measured by electrochemical impedance spectroscopy.The conductivity was improved with the increase of V-dopant content on La site.
基金supported by the National Basic Research Program of China(No.2016YFA0301004)the National Natural Science Foundation of China(No.21527803,21871009,and 21621061)funding from the Guangxi Natural Science Foundation(No.2019GXNSFGA245006).
文摘Rare-earth elements(REs)based oxide ion conductors show promising performance and potential applications in solid oxide fuel cells(SOFCs).To meet the requirements of intermediate-temperature(IT)SOFCs operating in the range of 600–800℃,oxide ion conductors with various structures were developed and summarized here,namely,pure oxide ion conductors and mixed oxide ionic and electronic conductors(MIECs).For the former,their structures range from traditional structure types(perovskite,fluorite,etc.)to new structures with isolated polyhedral units.For MIECs,perovskite and related structures have dominated this field due to their high oxide ion and electronic conductivities.Among these oxide ion conductors,REs play a crucial role in the modification of the structure and performances due to their unique characters,such as lanthanide contraction effect and stable valence(+3).This review emphasizes the structure–performance relationships among the REs.Furthermore,challenges particularly towards obtaining high oxide ion conductivity at low temperatures for lowering the operating temperature and thereby enhancing the device performance,and future prospects of RE-based oxide ion conductors are also discussed,together with advanced research techniques and new research directions being the possible strategies to overcome these challenges.
