The rational construction of a carbon base with a porous structure and incorporating effective dopants is an intriguing and challenging strategy used to develop advanced electrocatalysts for the oxygen reduction reaction (ORR). Herein, we synthesize a novel, efficient electrocatalyst comprised of three-dimensional (3D) porous graphene doped with Fe/N/S and incorporating Fe₃O₄ nanoparticles (Fe₃O₄/FeNSG). We use a melamine formaldehyde resin which plays the dual-functional roles of a soft template and a nitrogen-abundant source. The rational design of the Fe₃O₄/FeNSG-3 with its 3D porous architecture, abundant active sites (Fe–N–C, Fe₃O₄, pyridinic N, C–S–C, et al.), and large surface area (530.5 m² g⁻¹) makes it an efficient electrocatalyst towards ORR. The Fe₃O₄/FeNSG-3 catalyst shows a positive ORR onset potential (0.951 V) and half-wave potential (0.810 V), comparable to those of the commercial Pt/C electrocatalyst in alkaline media. Furthermore, the catalyst exhibits a four-electron transfer pathway, superior methanol tolerance and good stability. This work paves the way for preparing low-cost, active, stable, non-Pt group metal catalysts through regulating the active catalytic sites on 3D graphene with a porous architecture.

中文翻译：

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掺有Fe / N / S并掺入Fe ₃ O ₄纳米颗粒的多孔石墨烯可有效减少氧气†

合理构造具有多孔结构并掺入有效掺杂剂的碳碱是用于开发用于氧还原反应（ORR）的高级电催化剂的有趣且具有挑战性的策略。本文中，我们合成了一种新型的高效电催化剂，该催化剂由掺杂有Fe / N / S的三维（3D）多孔石墨烯组成，并掺入了Fe ₃ O ₄纳米颗粒（Fe ₃ O ₄ / FeNSG）。我们使用的三聚氰胺甲醛树脂具有软模板和富氮源的双重功能。Fe ₃ O ₄ / FeNSG-3的合理设计及其3D多孔结构，丰富的活性位点（Fe–N–C，Fe ₃ O ₄，吡啶二氮，C–SC，等。）和大表面积（530.5 m ² g ^-1）使其成为ORR的有效电催化剂。与碱性介质中的商用Pt / C电催化剂相比，Fe ₃ O ₄ / FeNSG-3催化剂显示正的ORR起始电势（0.951 V）和半波电势（0.810 V）。此外，该催化剂表现出四电子转移途径，优异的甲醇耐受性和良好的稳定性。这项工作通过调节具有多孔结构的3D石墨烯上的活性催化位，为制备低成本，活性，稳定的非Pt类金属催化剂铺平了道路。