The valorization of greenhouse gases, especially when focused on carbon dioxide, currently belongs to the main challenges of pro-environmental chemical processes. One of the important technologies in this field is dry methane reforming (DMR), leading to the so-called synthesis gas (CO + H2). However, to be efficient and economically viable, an active and stable catalyst is required. Ni-based systems can be recommended in this regard. This research aimed to investigate how nickel content can influence the activity of model NiOx/CeO2 catalysts in DMR. A series of NiOx/CeO2 samples of various nickel loadings (0–10 wt.%) were prepared through dry impregnation. The obtained samples were characterized through XRD, RS, N2-BET, DRIFT, SEM, UV/Vis-DR, and XPS. Nonlinear changes in surface properties of the investigated samples with increasing nickel concentration were found. The observed changes are mirrored both in the determined nickel speciation and in the corresponding catalytic activity. The highest activity was found for the catalyst containing 3 wt.%. of nickel.

中文翻译：

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通过优化镍含量改进 NiOx/CeO2 模型催化剂干甲烷重整活性的功能

温室气体的价值，特别是二氧化碳的价值，目前属于环保化学过程的主要挑战。该领域的重要技术之一是干甲烷重整 (DMR)，可产生所谓的合成气 (CO + H2)。然而，为了高效且经济可行，需要活性且稳定的催化剂。在这方面可以推荐基于镍的系统。本研究旨在研究镍含量如何影响 DMR 中 NiOx/CeO2 模型催化剂的活性。通过干浸渍制备了一系列不同镍含量（0-10 wt.%）的 NiOx/CeO2 样品。通过 XRD、RS、N2-BET、DRIFT、SEM、UV/Vis-DR 和 XPS 对所得样品进行了表征。发现随着镍浓度的增加，所研究样品的表面特性发生非线性变化。观察到的变化反映在确定的镍形态和相应的催化活性中。发现含有 3 wt.% 的催化剂活性最高。镍。