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In this paper, we reported the fuel cell performance with La0.8Sr0.2MnO3 (LSM)/Ce0.8Sm0.2O1.9 (SDC) composite cathode prepared from LSM powders of different particle sizes via the silk-printing technique. It was found that the change in particle size of LSM nanoparticle from 40 to 90 nm resulted in an increase in the maximum power density from 132 to 228 mW/cm2 at 650 ℃ with H2 as fuel and O2 as oxidant. And the polarization resistance of the electrode decreased from 2.547 to 1.034 Ω·cm2. Concerning the particle size of electrode materials, a higher activity was anticipated with smaller particles because a large number of TPB or electrode surface sites along with a higher porosity could be developed. However, this study showed that the electrode prepared with particles of larger diameter had fine and uniform micro-structure resulting in higher power density and lower overpotential, where homogeneous distribution of particles and pores was beneficial for increasing the electrochemical active area and the electronic conductivity of the electrodes as well as the gas diffusion for the reactants. 相似文献
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齐齐哈尔市耕地面积2 800万亩,农业人口320 万,粮食生产能力稳定在100亿斤以上,是国家重要的商品粮基地和畜产品基地。然而,这个城市位于黑龙江省西部旱区,十年九旱,旱灾频繁发生,年均受旱面积 2 000万亩以上,最高年份达到2 700万亩,年均因灾减产粮食30亿斤,最高年份达到50亿斤以上。因此, 干旱已经成为制约齐齐哈尔市农村经济发展的障碍性因素。认真分析干旱的成因,找准症结,采取措施防旱、治旱,既是发展农村经济的要求,也是新农村建设过程中一个必须破解的问题。 相似文献
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