Chen Yingjie, Gong Chong, Shi Zhihao, Chen Di, Chen Xing, Zhang Qian, Pang Beili, Feng Jianguang, Yu Liyan, Dong Lifeng
College of Materials Science and Engineering, Qingdao University of Science and Technology, Qingdao 266042, China.
Shandong Engineering Research Center of Green and High-value Marine Fine Chemical, Weifang University of Science and Technology, Shouguang 262700, China.
J Colloid Interface Sci. 2021 Aug 15;596:206-214. doi: 10.1016/j.jcis.2021.03.145. Epub 2021 Mar 29.
A melt-salt-assisted method is utilized to construct an onion-like hybrid with Co/CoO nanoparticles embedded in graphitic Fe-N-doped carbon shells (Co/CoO@FeNC) as a bifunctional electrocatalyst. The iron-polypyrrole (Fe-PPy) is firstly prepared with a reverse emulsion. Direct pyrolysis of Fe-PPy yields turbostratic Fe-N-doped carbon (FeNC) with excellent oxygen reduction reaction (ORR) electrocatalysis, while the melt salt (CoCl) mediated pyrolysis of Fe-PPy obtains onion-like Co/CoO@FeNC with a reversible overvoltage value of 0.695 V, largely superior to Pt/C and IrO (0.771 V) and other Co-based catalysts reported so far. The ORR activity is mainly due to the graphitic FeNC and further enhanced by CoN bonds, whereas the oxygen evolution reaction (OER) activity is principally due to the Co/CoO composite. Concurrently, Co/CoO@FeNC as cathode catalyst enables Zn-air battery with a high open circuit voltage of 1.42 V, a peak power density of 132.8 mW cm, a specific capacity of 813 mAh g, and long-term stability.
采用熔盐辅助法构建了一种洋葱状杂化物，该杂化物以嵌入石墨化铁氮掺杂碳壳（Co/CoO@FeNC）中的Co/CoO纳米颗粒作为双功能电催化剂。首先通过反相乳液制备铁 - 聚吡咯（Fe-PPy）。Fe-PPy直接热解可得到具有优异氧还原反应（ORR）电催化性能的乱层铁氮掺杂碳（FeNC），而Fe-PPy经熔盐（CoCl）介导热解可得到洋葱状的Co/CoO@FeNC，其可逆过电压值为0.695 V，大大优于Pt/C和IrO（0.771 V）以及迄今为止报道的其他钴基催化剂。ORR活性主要归因于石墨化FeNC，并通过CoN键进一步增强，而析氧反应（OER）活性主要归因于Co/CoO复合材料。同时，Co/CoO@FeNC作为阴极催化剂可使锌空气电池具有1.42 V的高开路电压、132.8 mW cm的峰值功率密度、813 mAh g的比容量以及长期稳定性。
