ie7b03417_si_001.pdf (3.81 MB)
Improved Oxygen Reduction Reaction Performance of Co Confined in Ordered N‑Doped Porous Carbon Derived from ZIF-67@PILs
journal contribution
posted on 2017-09-07, 00:00 authored by Xiang Zhou, Yi-jing Gao, Sheng-wei Deng, Shan Cheng, Shao-hua Zhang, Hui Hu, Gui-lin Zhuang, Xing Zhong, Jian-guo WangDiffusion and activation
of reaction species are two critical factors
of oxygen reduction reaction (ORR). Diffusion property is essentially
dominated by transmission of reaction species in the channel of catalysts.
Herein, we report a facile method to prepare ordered-carbon coated
Co nanoparticle (Co@O-NPC). Specifically, we mixed ZIF-67 MOF microcrystal
into an ionic liquid monomer which resulted in ZIF-67@PILs composites.
Subsequently, Co@O-NPC was obtained by the high-temperature pyrolysis
of ZIF-67@PILs. Electrochemical measurements show that it possesses
superior ORR property compared to commercial Pt/C. A combination of
molecular dynamics (MD) calculations and contrast experimental results
reveals that the ordered porous carbon structure can improve the diffusivity
of reaction species more effectively than disordered carbon, thereby
enhancing ORR property. Moreover, DFT calculation results demonstrate
that the catalytically active sites are located on the cavity bottom
of Co@O-NPC and uncover the synergistic effect between Co nanoparticles
and N-doped porous carbon.