Efficient oxidation catalysts are important in many current industrial processes, including the selective oxidation of methanol to formaldehyde. Vanadium-containing catalysts have been shown to be effective selective oxidation catalysts for certain reactions, and research continues to examine their applicability to other reactions of interest. Several VOx/Fe2O3 shell-core catalysts with varying VOx coverage have been produced to investigate the stability of VOx monolayers and their selectivity for methanol oxidation. Catalyst formation proceeds via a clear progression of distinct surface species produced during catalyst calcination. At 300 °C the selective VOx overlayer has formed; by 500 °C a sandwich layer of FeVO4 arises between the VOx shell and the Fe2O3 core, inhibiting iron cation participation in the catalysis and enhancing catalyst selectivity. The resulting catalysts, comprising a shell-subshell-core system of VOx/FeVO4/Fe2O3, possess good catalytic activity and selectivity to formaldehyde.

中文翻译：

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VOx / Fe2O3壳核催化剂，用于甲醇选择性氧化为甲醛。

高效的氧化催化剂在许多当前的工业过程中都很重要，包括将甲醇选择性氧化为甲醛。含钒催化剂已被证明对某些反应是有效的选择性氧化催化剂，并且研究继续研究它们对其他感兴趣的反应的适用性。已生产出几种具有不同VOx覆盖率的VOx / Fe2O3壳核催化剂，以研究VOx单层的稳定性及其对甲醇氧化的选择性。催化剂的形成是通过催化剂煅烧过程中产生的不同表面物质的明显进展来进行的。在300°C时，形成了选择性的VOx覆盖层。在500°C时，VOx外壳和Fe2O3芯之间会形成一层FeVO4夹层，抑制铁阳离子参与催化并提高催化剂的选择性。所得的包含VOx / FeVO4 / Fe2O3的壳-壳-壳-核体系的催化剂具有良好的催化活性和对甲醛的选择性。