The rational design of low‐cost and earth‐abundant perovskite oxide alternatives as highly efficient and robust electrocatalysts for the oxygen reduction reaction (ORR) is desirable but remains a great challenge. Herein, we developed a simple MnO₂‐mediated synthetic approach to Mn₃O₄@CaMn₇O₁₂ core@shell nanorods by impregnating MnO₂ nanorods with a certain amount of Ca(NO₃)₂ solution (Mn : Ca=15 : 1), followed by a calcination process at 850 °C in air. By adjusting the Mn : Ca molar ratios, Ca−Mn oxides with different structures can also be prepared. Benefiting from the intrinsic characteristics of CaMn₇O₁₂ perovskite oxides and the structural advantage of nanorods, Mn₃O₄@CaMn₇O₁₂ core@shell nanorods exhibit high ORR activity with a positive onset potential of 0.90 V and half‐wave potential of 0.75 V. Also, they have an excellent tolerance ability to methanol. More importantly, the work may pave a new avenue to design other novel electrocatalysts with high performance and stability towards energy conversion and storage applications.

中文翻译：

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MnO2介导的Mn3O4 @ CaMn7O12核@壳纳米棒的合成用于电催化氧还原反应

合理设计低成本和富地球的钙钛矿氧化物替代品作为用于氧还原反应（ORR）的高效，稳健的电催化剂是可取的，但仍然是一个巨大的挑战。在此，我们开发了一种简单的MnO ₂介导的合成方法与Mn ₃ ö ₄ @CaMn ₇ ö ₁₂通过浸渍的MnO芯@壳纳米棒_2个纳米棒与一定量的Ca（NO的₃）₂的Ca = 15：溶液（MN： 1），然后在850°C的空气中进行煅烧。通过调节Mn：Ca的摩尔比，还可以制备具有不同结构的Ca-Mn氧化物。受益于CaMn ₇ O的固有特性_12种钙钛矿氧化物和纳米棒Mn ₃ O ₄ @CaMn ₇ O ₁₂核壳纳米棒的结构优势显示出高ORR活性，正起始电势为0.90 V，半波电势为0.75V。对甲醇的耐受能力。更重要的是，这项工作可能为设计其他新型的电催化剂铺平了道路，该新型电催化剂具有高性能和高稳定性，适用于能量转换和存储应用。