Abstract Two ZrO2 supports with either monoclinic (m-ZrO2) or tetragonal (t-ZrO2) crystal phases were obtained under hydrothermal reaction conditions. ZrO2-supported Co3O4 catalysts (Co3O4/m-ZrO2 and Co3O4/t-ZrO2) were subsequently prepared through an impregnation-loading route. The effects of zirconia crystal phases on the catalytic decomposition of N2O over Co3O4/ZrO2 catalysts were investigated in the presence or absence of contaminants (O2/H2O/NO) in the feed gas. The catalytic results indicated that Co3O4/m-ZrO2 was more active than Co3O4/t-ZrO2 during N2O decomposition. ZrO2 supports and/or Co3O4/ZrO2 catalysts were characterized via multitudinous techniques to explore the relationships between the structures, catalytic activities, and active sites of samples. The experimental results confirmed that there were more Co oxides dispersed on m-ZrO2 than t-ZrO2, and Co3O4/m-ZrO2 had superior textural properties than Co3O4/t-ZrO2. Furthermore, Co3O4/m-ZrO2 possessed a relatively higher redox Co2+/Co3+ activity, more surface Co2+, and more surface oxygen vacancies than Co3O4/t-ZrO2 due to strong interactions between the m-ZrO2 support and active Co oxides. m-ZrO2 also contributed to the formation of stable Co2+. Moreover, the Co3O4/m-ZrO2 surface contained abundant basic sites that helped improve the electron-donating ability of Co2+ which further decreased the activation energy for N2O decomposition.

中文翻译：

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氧化锆晶相对Co3O4/ZrO2催化剂上N2O催化分解的影响

摘要 在水热反应条件下获得了两种单斜(m-ZrO2)或四方(t-ZrO2)晶相的ZrO2载体。随后通过浸渍加载路线制备了 ZrO2 负载的 Co3O4 催化剂（Co3O4/m-ZrO2 和 Co3O4/t-ZrO2）。在原料气中存在或不存在污染物 (O2/H2O/NO) 的情况下，研究了氧化锆晶相对 Co3O4/ZrO2 催化剂上 N2O 催化分解的影响。催化结果表明，在 N2O 分解过程中，Co3O4/m-ZrO2 比 Co3O4/t-ZrO2 更具活性。ZrO2 载体和/或 Co3O4/ZrO2 催化剂通过多种技术进行表征，以探索样品的结构、催化活性和活性位点之间的关系。实验结果证实，与 t-ZrO2 相比，分散在 m-ZrO2 上的 Co 氧化物更多，并且 Co3O4/m-ZrO2 具有优于 Co3O4/t-ZrO2 的织构性能。此外，由于 m-ZrO2 载体和活性 Co 氧化物之间的强相互作用，Co3O4/m-ZrO2 比 Co3O4/t-ZrO2 具有相对更高的氧化还原 Co2+/Co3+ 活性、更多的表面 Co​​2+ 和更多的表面氧空位。m-ZrO2 也有助于形成稳定的 Co2+。此外，Co3O4/m-ZrO2 表面含有丰富的碱性位点，有助于提高 Co2+ 的给电子能力，从而进一步降低 N2O 分解的活化能。由于 m-ZrO2 载体和活性 Co 氧化物之间的强相互作用，表面氧空位比 Co3O4/t-ZrO2 多。m-ZrO2 也有助于形成稳定的 Co2+。此外，Co3O4/m-ZrO2 表面含有丰富的碱性位点，有助于提高 Co2+ 的给电子能力，从而进一步降低 N2O 分解的活化能。由于 m-ZrO2 载体和活性 Co 氧化物之间的强相互作用，表面氧空位比 Co3O4/t-ZrO2 多。m-ZrO2 也有助于形成稳定的 Co2+。此外，Co3O4/m-ZrO2 表面含有丰富的碱性位点，有助于提高 Co2+ 的给电子能力，从而进一步降低 N2O 分解的活化能。