Enhancement of Mass Transport for Oxygen Reduction Reaction Using Petal-Like Porous Fe-NC Nanosheet

作者：Shao, Chunfeng; Zhuang, Shiguang; Zhang, Haocheng; Jiang, Qike; Xu, Xiaoyan; Ye, Jianshan; Li, Baitao^*; Wang, Xiujun^*

来源：Small, 2021, 17(6): 2006178.

DOI：10.1002/smll.202006178

• air cathode
• iron&#8208
• nitrogen carbon
• oxygen reduction reaction
• single&#8208
• atom catalysts

Nitrogen-coordinated single-atom catalysts (SACs) have emerged as a new frontier for accelerating oxygen reduction reaction (ORR) owing to the optimal atom efficiency and fascinating properties. However, augmenting the full exposure of active sites is a crucial challenge in terms of simultaneously pursuing high metal loading of SACs. Here, petal-like porous carbon nanosheets with densely accessible Fe-N-4 moieties (FeNC-D) are constructed by combining the space-confinement of silica and the coordination of diethylenetriaminepentaacetic acid. The resulted FeNC-D catalyst possesses an enhanced mesoporosity and a balanced hydrophobicity/hydrophilicity, which can facilitate mass transport and advance the exposure of inaccessible Fe-N-4 sites, resulting in efficient utilization of active sites. By virtue of the petal-like porous architecture with maximized active site density, FeNC-D demonstrates superior ORR performance in a broad pH range. Remarkably, when utilized as the air cathode in Zn-air battery (ZAB) and microbial fuel cell (MFC), the FeNC-D-based device displays a large power density (356 mW cm(-2) for ZAB and 1041.3 mW m(-2) for MFC) and possesses remarkable stability, substantially outperforming the commercial Pt/C catalyst.

• 单位
  中国科学院