The effect of the oxidation degree of a nickel foil surface on the rate of catalytic oxidation of ethylene was studied by a pulse method at 600 and 700°C. It was shown that a reduced metallic surface demonstrated a high activity in partial ethylene oxidation, whereas a partially oxidized surface with an oxidation degree of ~24 formal O₂ monolayers, in the total oxidation of C₂H₄. A SEM investigation has revealed that the oxidized surface was partially coated with nickel oxide nanocrystals. A further increase in the surface oxidation degree led to a continuous coverage of the Ni surface with oxide crystals and a dramatic decrease of catalytic activity. In addition, a low maximum of total ethylene oxidation was observed at 700°C in the range of surface oxidation degree of 95–135 O₂ monolayers.

中文翻译：

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镍箔表面的氧化程度对其在乙烯氧化反应中催化活性的影响

通过脉冲法在600和700℃下研究了镍箔表面的氧化度对乙烯的催化氧化速率的影响。结果表明，还原的金属表面在部分乙烯氧化中表现出高活性，而在C ₂ H ₄的总氧化中，部分氧化的氧化程度约为〜24形式O ₂单层。。SEM研究表明，氧化的表面部分地被氧化镍纳米晶体覆盖。表面氧化度的进一步增加导致Ni表面被氧化物晶体连续覆盖并且催化活性急剧降低。此外，在表面氧化度为95–135 O ₂单层的范围内，在700℃观察到的总乙烯氧化最大值较低。