Herein, supported Ni/MCF-17 catalysts with the size of nickel nanocrystal in the range of 1.5–8.0 nm were synthesized and employed for CO_x-free hydrogen production for fuel cells via the ammonia decomposition reaction. Characterized by a variety of techniques, the results show that nickel particles are in a highly dispersed state with a uniform particle size for each catalyst. Furthermore, the influence of particle size on the catalytic performance has been investigated. It was later revealed that Ni nanoparticles with different particle sizes exhibited significant differences in catalyzing the CO_x-free hydrogen production reaction. Moreover, the catalyst with the Ni nanoparticle size around 3.0 nm exhibited highest catalytic activity at each reaction temperature; this could be explained by the presence of high B₅ active sites on the Ni-based catalyst surface.

中文翻译：

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Ni / MCF-17负载型催化剂在无CO _x产氢中的尺寸结构与催化性能的相关性†

在此，合成了镍纳米晶尺寸在1.5–8.0 nm范围内的负载型Ni / MCF-17催化剂，并通过氨分解反应将其用于燃料电池的无CO _x制氢。通过各种技术进行表征，结果表明，镍颗粒处于高度分散的状态，每种催化剂的粒径均一。此外，已经研究了粒径对催化性能的影响。后来发现，具有不同粒径的Ni纳米颗粒在催化CO _x方面表现出显着差异。无氢生产反应。此外，Ni纳米颗粒尺寸约为3.0 nm的催化剂在每个反应温度下均表现出最高的催化活性。这可以通过在镍基催化剂表面上存在高的B ₅活性位来解释。