质子导体(Ce0.8La0.2)1－xCaxO2－δ 在合成氨中的应用

利用溶胶-凝胶法合成了萤石型稀土复合氧化物(Ce_0.8La_0.2)_1－xCa_xO_2－δ, 利用XRD、TEM和SEM对样品进行表征. 电化学方法研究表明, 合成样品在400～800 ℃温度范围内具有质子导电特性. 将(Ce_0.8La_0.2)_1－xCa_xO>_2－δ高温烧结体用于固态质子传导电池, 在常压下以氮气和氢气为原料合成氨气, 并确定了合成氨的适宜条件. 650 ℃时Ce_0.8La_0.2O_2－δ和(Ce_0.8La_0.2)_0.975Ca_0.025O_2－δ对应的氨产率分别达7.2×10^－9和7.5×10^－9 mol•s^－9•cm^－9.

Application of Proton Conductors (Ce0.8 La0.2)1-xCaxO2-δ in Synthesis of Ammonia

Fluorite-type rare earth complex oxides of (Ce_0.8La_0.2)_1－xCa_xO_2－δwere prepared by a sol-gel process. Crystalstructure and microstructure of the product were characterized by X-ray diffraction (XRD), transmisson electronmicroscopy (TEM) and scanning electron microscopy (SEM). Electrical conductivity measurements performed in N₂/H₂ over the temperature range of 400 to 800 ℃ showed that conductivity was enhanced by extrinsic doping. Ammonia was synthesized from nitrogen and hydrogen under atmospheric pressure in a solid state proton conducting cell reactor, and the optimal temperature determined in the ammonia production was 650 ℃. The effect of non-Faradaic electrochemical modification of catalytic activity (NEMCA) explained the effect of imposed potential on the rate of NH3 synthesis. The rates of evolution of ammonia were 7.2×10^－9 mol•s^-1•cm^-2 and 7.5×10^－9 mol•s^-1•cm^-2 for Ce_0.8La_0.2O_2－δ and (Ce_0.8La_0.2)_0.975Ca_0.025O_2－δrespectively at 650 ℃.