The design and facile synthesis of active, robust, cheap, and earth-abundant electrocatalysts to replace precious Pt catalysts is highly desirable for the cathodic oxygen reduction reaction (ORR) in fuel cells and rechargeable metal batteries. However, maximizing the catalytic activity and stability of the electrocatalysts in catalyzing ORR is significantly important but still remains challenge. To address this issue, we herein reported an effective strategy that fabricate the cobalt nanoparticles encapsulated with defect-rich graphitized carbon shell in the hierarchical porous N-doped carbon aerogel (Co/NCA), which can simultaneously enhance the electrochemical stability while boosting the electrocatalytic activity for ORR. The desirable combination of the Co nanoparticles encapsulated with defect-rich graphitic carbon shells coupling with Co−N_x sites, the large accessible surface-active sites, and the hierarchical porous structure give rise to the superior electrocatalytic activity and stability for ORR in wide pH range. As expect, the as-obtained catalyst exhibits high efficiency for ORR with an onset potential of 0.95 V (versus reversible hydrogen electrode, vs. RHE) and a half-wave potential of 0.83 V in 0.1 M KOH, comparable to the commercial Pt/C. Importantly, the catalyst also provides excellent ORR properties in acidic and neutral media with almost a 4e⁻ pathway and superior durability and methanol tolerance, showing a potential as electrocatalysts for practical applications.

对于燃料电池和可充电金属电池中的阴极氧还原反应（ORR），非常需要设计和容易地合成活性，坚固，便宜且富含地球的电催化剂，以代替珍贵的Pt催化剂。然而，最大化电催化剂在催化ORR中的催化活性和稳定性是非常重要的，但是仍然是挑战。为了解决这个问题，我们在本文中报告了一种有效的策略，该策略可在分层的多孔N掺杂碳气凝胶（Co / NCA）中制造用富缺陷石墨化碳壳封装的钴纳米颗粒，该纳米颗粒可以同时增强电化学稳定性，同时增强电催化性能。 ORR的活动。富含缺陷的石墨碳壳与Co-N偶联的Co纳米颗粒的理想组合_x位，大的可及表面活性位和分层的多孔结构导致在宽pH范围内对ORR具有出色的电催化活性和稳定性。不出所料，所制得的催化剂对ORR的效率很高，在0.1 M KOH中的起始电势为0.95 V（相对于可逆氢电极，相对于RHE），半波电势为0.83V。 C。重要的是，该催化剂还提供了在酸性和中性介质优良ORR性能几乎一个4E ^-通路和优异的耐久性和甲醇耐受性，示出了电势电催化剂用于实际应用。