The design of core–shell structure catalysts with excellent activity, stability and water resistance is one of the effective strategies to realize their application in catalytic combustion of VOCs. Since octadecyltrichlorosilane (OTS) is an excellent hydrophobic coating, it was used to prepare superhydrophobic surfaces by forming hydrophobic monolayers on the surface of CoMnO_x nanostructured templates. The CoMnO_x@OTS core–shell structures were successfully constructed by overcoating OTS on the surface of CoMnO_x-MOF nanocubes and evaluated for the catalytic combustion of toluene. The thickness of the CoMnO_x@OTS cubic crystal was adjusted by controlling the content of OTS (2 wt%, 4 wt% and 10 wt%). Due to the synergistic effect between CoMnO_x and OTS, CoMnO_x@OTS-1 exhibited superior catalytic activity, stability and water resistance. The catalytic activity of CoMnO_x@OTS-1 was consistently maintained at about 90% in the presence of 5 vol% H₂O. The content of the OTS hydrophobic layer at 2 wt% reached the optimum water resistance. This is mainly attributed to the role and contribution of the hydrophobic functional group –OH from the OTS surface, which can greatly prevent the adsorption of water molecules on the active site. This work reveals new ideas for the preparation of core–shell structured cubic crystals using hydrophobic layer-coated bimetallic oxides, as well as a deeper understanding of the catalytic oxidation of toluene.

中文翻译：

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设计具有优异耐水性的核壳结构 CoMnOx@OTS 立方催化剂，用于 VOC 的低温催化燃烧


设计具有优异活性、稳定性和耐水性的核壳结构催化剂是实现其在VOCs催化燃烧中应用的有效策略之一。由于十八烷基三氯硅烷（OTS）是一种优异的疏水涂层，因此通过在CoMnO _x 纳米结构模板表面形成疏水单层来制备超疏水表面。通过在CoMnO _x -MOF纳米立方体表面涂覆OTS，成功构建了CoMnO _x @OTS核壳结构，并对其对甲苯的催化燃烧进行了评估。通过控制OTS的含量(2wt％、4wt％和10wt％)来调节CoMnO _x @OTS立方晶体的厚度。由于CoMnO _x 与OTS之间的协同作用，CoMnO _x @OTS-1表现出优异的催化活性、稳定性和耐水性。在 5 vol% H ₂ O 存在下，CoMnO _x @OTS-1 的催化活性始终保持在 90% 左右。OTS 疏水层含量为 2 wt %达到最佳耐水性。这主要归功于OTS表面疏水性官能团-OH的作用和贡献，它可以极大地阻止水分子在活性位点上的吸附。这项工作揭示了利用疏水层包覆双金属氧化物制备核壳结构立方晶体的新思路，以及对甲苯催化氧化的更深入理解。