A precursor of BaCe 0.9 Nd 0.1 O 3-δ solid electrolyte was synthesized by the sol-gel method and sintered at14 00℃.The obtained gels and powder were characterized by differential and ther mogravimetric thermal analy...A precursor of BaCe 0.9 Nd 0.1 O 3-δ solid electrolyte was synthesized by the sol-gel method and sintered at14 00℃.The obtained gels and powder were characterized by differential and ther mogravimetric thermal analysis(TG-DTA),X-ray diffraction(XRD),transmissi on electron microscopy(TEM).Using the sintered samples as solid electrolyte a nd silver-palladium alloy as electrodes,electrical conductivities under differ ent gas ambiences at intermediate temperature(400～600℃)were measured. In moist hydrogen atmosphere,the conduction is a little higher than that of dry hydrogen atmosphere.In hydrogen atmosphere,proton conduction may predominate ,leading to an increase in conductivity and a decrease in activation energy.展开更多
The structure and catalytic properties of SrTi0.9M0.1O3- δ (M=Mg,Al, Zr) perovskite type catalysts for oxidative coupling of methane (OCM) have been studied by using X ray diffraction (XRD),X ray photoelectron spectr...The structure and catalytic properties of SrTi0.9M0.1O3- δ (M=Mg,Al, Zr) perovskite type catalysts for oxidative coupling of methane (OCM) have been studied by using X ray diffraction (XRD),X ray photoelectron spectroscopy (XPS) and temperature programmed desorption of oxygen(O2 TPD) methods. It has been shown that doping the cations of lower valence (e.g. Mg2+ , Al3+ ) to the B site of SrTi0.9M0.1O3- δ perovskite type catalysts results in the higher content of adsorbed oxygen species on the surface of catalysts and thus higher C2 selectivity for OCM reaction. It is suggested that the oxygen vacancies of SrTi0.9M0.1O3- δ (M=Mg, Al, Zr) perovskite type catalysts are the sites responsible for oxygen activation, and the adsorbed oxygen species on the surface of SrTi0.9M0.1O3- δ catalysts are the main active species for OCM reaction.展开更多
文摘A precursor of BaCe 0.9 Nd 0.1 O 3-δ solid electrolyte was synthesized by the sol-gel method and sintered at14 00℃.The obtained gels and powder were characterized by differential and ther mogravimetric thermal analysis(TG-DTA),X-ray diffraction(XRD),transmissi on electron microscopy(TEM).Using the sintered samples as solid electrolyte a nd silver-palladium alloy as electrodes,electrical conductivities under differ ent gas ambiences at intermediate temperature(400～600℃)were measured. In moist hydrogen atmosphere,the conduction is a little higher than that of dry hydrogen atmosphere.In hydrogen atmosphere,proton conduction may predominate ,leading to an increase in conductivity and a decrease in activation energy.
文摘The structure and catalytic properties of SrTi0.9M0.1O3- δ (M=Mg,Al, Zr) perovskite type catalysts for oxidative coupling of methane (OCM) have been studied by using X ray diffraction (XRD),X ray photoelectron spectroscopy (XPS) and temperature programmed desorption of oxygen(O2 TPD) methods. It has been shown that doping the cations of lower valence (e.g. Mg2+ , Al3+ ) to the B site of SrTi0.9M0.1O3- δ perovskite type catalysts results in the higher content of adsorbed oxygen species on the surface of catalysts and thus higher C2 selectivity for OCM reaction. It is suggested that the oxygen vacancies of SrTi0.9M0.1O3- δ (M=Mg, Al, Zr) perovskite type catalysts are the sites responsible for oxygen activation, and the adsorbed oxygen species on the surface of SrTi0.9M0.1O3- δ catalysts are the main active species for OCM reaction.
