Nano size nickel copper ferrite powders (NiCuFe204) and nickel copper zinc ferrite powders have been prepared by a citrate gel precursor method. The resulting powders were characterized by X-ray diffraction (XRD) ...Nano size nickel copper ferrite powders (NiCuFe204) and nickel copper zinc ferrite powders have been prepared by a citrate gel precursor method. The resulting powders were characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM). The results showed that nickel copper ferrites and nickel copper zinc ferrites were also in the nanosaele. The NiCu ferrite powders showed extensive XRD fine broadening and sizes of crystals were calculated (from the XRD line broadening) as 26 run-44 run over the temperature range is 200-800℃. The NiCuZn ferrite powders showed XRD line broadening and sizes of of crystals were calculated 46-65 nm over 200-800℃.展开更多
A series of solid electrolytes, (Ce 0.8 Ln 0.2 ) 1- x M x O 2-δ (Ln= La, Nd, Sm, Gd, M:Alkali earth), were prepared by amorphous citrate gel method. XRD patterns indicate that a pure fluorite...A series of solid electrolytes, (Ce 0.8 Ln 0.2 ) 1- x M x O 2-δ (Ln= La, Nd, Sm, Gd, M:Alkali earth), were prepared by amorphous citrate gel method. XRD patterns indicate that a pure fluorite phase is formed at 800 ℃. The electrical conductivity and the AC impedance spectra were measured. XPS spectra show that the oxygen vacancies increase owing to the MO doping, which results in the increase of the oxygen ionic transport number and conductivity. The performance of ceria based solid electrolyte is improved. The effects of rare earth and alkali earth ions on the electricity were discussed. The open circuit voltages and maximum power density of planar solid oxide fuel cell using (Ce 0.8 Sm 0.2 ) 1-0.05 Ca 0.05 O 2- δ as electrolyte are 0.86 V and 33 mW·cm -2 , respectively.展开更多
文摘Nano size nickel copper ferrite powders (NiCuFe204) and nickel copper zinc ferrite powders have been prepared by a citrate gel precursor method. The resulting powders were characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM). The results showed that nickel copper ferrites and nickel copper zinc ferrites were also in the nanosaele. The NiCu ferrite powders showed extensive XRD fine broadening and sizes of crystals were calculated (from the XRD line broadening) as 26 run-44 run over the temperature range is 200-800℃. The NiCuZn ferrite powders showed XRD line broadening and sizes of of crystals were calculated 46-65 nm over 200-800℃.
文摘A series of solid electrolytes, (Ce 0.8 Ln 0.2 ) 1- x M x O 2-δ (Ln= La, Nd, Sm, Gd, M:Alkali earth), were prepared by amorphous citrate gel method. XRD patterns indicate that a pure fluorite phase is formed at 800 ℃. The electrical conductivity and the AC impedance spectra were measured. XPS spectra show that the oxygen vacancies increase owing to the MO doping, which results in the increase of the oxygen ionic transport number and conductivity. The performance of ceria based solid electrolyte is improved. The effects of rare earth and alkali earth ions on the electricity were discussed. The open circuit voltages and maximum power density of planar solid oxide fuel cell using (Ce 0.8 Sm 0.2 ) 1-0.05 Ca 0.05 O 2- δ as electrolyte are 0.86 V and 33 mW·cm -2 , respectively.