Natural tea-leaf-derived, ternary-doped 3D porous carbon as a high-performance electrocatalyst for the oxygen reduction reaction

• Published in: Nano research 2016-05, Vol.9 (5), p.1244-1255
• Main Authors: Guo, Zhaoyan, Xiao, Zhen, Ren, Guangyuan, Xiao, Guozheng, Zhu, Ying, Dai, Liming, Jiang, Lei
• Format: Article
• Language: English
• Subjects: Alternative energy sources; Atomic/Molecular Structure and Spectra; Batteries; Biomedicine; Biotechnology; Carbon; Carbonization; Catalysis; Catalysts; Chemical reduction; Chemistry and Materials Science; Condensed Matter Physics; Coordination compounds; Electrocatalysts; Electrochemistry; Energy conversion; Iron; Leaves; Materials Science; Nanotechnology; Organic compounds; Oxygen; Oxygen reduction reactions; Platinum; Polyphenols; Porous materials; Pyrolysis; Research Article; Structural hierarchy; Tea; Three dimensional; 三元; 三维结构; 多孔碳; 天然来源; 掺杂; 氧还原反应; 茶叶; 高效催化剂
• ISSN: 1998-0124; 1998-0000
• DOI: 10.1007/s12274-016-1020-2

To commercialize fuel cells and metal-air batteries, cost-effective, highly active catalysts for the oxygen reduction reaction （ORR） must be developed. Herein, we describe the development of low-cost, heteroatom （N, P, Fe） ternary-doped, porous carbons （HDPC）. These materials are prepared by one-step pyrolysis of natural tea leaves treated with an iron salt, without any chemical and physical activation. The natural structure of the tea leaves provide a 3D hierarchical porous structure after carbonization. Moreover, heteroatom containing organic compounds in tea leaves act as precursors to functionalize the resultant carbon frameworks. In addition, we found that the polyphenols present in tea leaves act as ligands, reacting with Fe ions to form coordination compounds; these complexes acted as the precursors for Fe and N active sites. After pyrolysis, the as-prepared HDPC electrocatalysts, especially HDPC-800 （pyrolyzed at 800℃）, had more positive onsets, half-wave potentials, and higher catalytic activities for the ORR, which proceeds via a direct four-electron reaction pathway in alkaline media, similar to commercial Pt/C catalysts. Furthermore, HDPC-X also showed enhanced durability and better tolerance to methanol crossover and CO poisoning effects in comparison to commercial Pt/C, making them promising alternatives for state-of-the-art ORR electrocatalysts for electrochemical energy conversion. The method used here provides valuable guidelines for the design of high-performance ORR electrocatalysts from natural sources at the industrial scale.