A simple method is developed to assemble Mo₂C nanocrystals on the surfaces of hollow, highly conductive mesoporous nanoparticles. Diblock copolymer (PS-b-PEO) micelles are used as templates to assist in the fast complexation of molybdate (MoO₄²⁻) and polydopamine (PDA) precursors to make hollow precursor MoO₄²⁻/PDA/PS-b-PEO particles. Then these particles are carbonized to generate mesoporous N-doped carbon nanosheets riddled with ultrafine molybdenum carbide (Mo₂C) nanoparticles (MMo₂C/NCS). An N-doped carbon matrix serves as an electron conductor and helps to prevent the aggregation of the Mo₂C nanoparticles. The Mo₂C nanoparticles in turn enhance the catalytic performance for the oxygen reduction reaction (ORR). The unique mesoporous 2D nanosheet and its derived 3D hollow structure expose numerous active catalytic sites while enabling free diffusion of the electrolyte and mass transfer. Based on these properties, MMo₂C/NCS show enhanced catalytic activity for the ORR.

中文翻译：

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在N掺杂的碳纳米片上组装由超细Mo ₂ C纳米粒子组成的中空介孔纳米结构，以有效地电催化还原氧气

开发了一种简单的方法将Mo ₂ C纳米晶体组装在中空，高导电性介孔纳米颗粒的表面上。二嵌段共聚物（PS- b -PEO）胶束用作模板，以协助钼酸盐的快速络合氧化钼（MoO ₄ ^2-）和聚多巴胺（PDA）的前体，使中空前体的MoO ₄ ^{2- /} PDA / PS- b -PEO粒子。然后将这些颗粒碳化以生成中孔掺N的碳纳米片，其中布满了超细碳化钼（Mo ₂ C）纳米颗粒（MMo ₂ C / NCS）。N掺杂的碳基体用作电子导体，有助于防止Mo ₂的聚集C纳米粒子。Mo ₂ C纳米颗粒反过来又增强了氧还原反应（ORR）的催化性能。独特的介孔2D纳米片及其衍生的3D空心结构暴露了许多活性催化位点，同时使电解质能够自由扩散和传质。基于这些性质，MMo ₂ C / NCS对ORR表现出增强的催化活性。