One-step ball milling-prepared nano Fe2O3 and nitrogen-doped graphene with high oxygen reduction activity and its application in microbial fuel cells |
| |
Authors: | Xingguo Guo Qiuying Wang Ting Xu Kajia Wei Mengxi Yin Peng Liang Xia Huang Xiaoyuan Zhang |
| |
Affiliation: | State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China |
| |
Abstract: | ? Nano Fe2O3 and N-doped graphene was prepared via a one-step ball milling method. ? The maximum power density of Fe-N-G in MFC was 390% of that of pristine graphite. ? Active sites like nano Fe2O3, pyridinic N and Fe-N groups were formed in Fe-N-G. ? The improvement of Fe-N-G was due to full exposure of active sites on graphene. Developing high activity, low-cost and long durability catalysts for oxygen reduction reaction is of great significance for the practical application of microbial fuel cells. The full exposure of active sites in catalysts can enhance catalytic activity dramatically. Here, novel Fe-N-doped graphene is successfully synthesized via a one-step in situ ball milling method. Pristine graphite, ball milling graphene, N-doped graphene and Fe-N-doped graphene are applied in air cathodes, and enhanced performance is observed in microbial fuel cells with graphene-based catalysts. Particularly, Fe-N-doped graphene achieves the highest oxygen reduction reaction activity, with a maximum power density of 1380±20 mW/m2 in microbial fuel cells and a current density of 23.8 A/m2 at –0.16 V in electrochemical tests, which are comparable to commercial Pt and 390% and 640% of those of pristine graphite. An investigation of the material characteristics reveals that the superior performance of Fe-N-doped graphene results from the full exposure of Fe2O3 nanoparticles, pyrrolic N, pyridinic N and excellent Fe-N-G active sites on the graphene matrix. This work not only suggests the strategy of maximally exposing active sites to optimize the potential of catalysts but also provides promising catalysts for the use of microbial fuel cells in sustainable energy generation. |
| |
Keywords: | Microbial fuel cells Air cathodes Nano Fe2O3 and nitrogen-doped graphene Oxygen reduction reaction |
|
| 点击此处可从《Frontiers of Environmental Science & Engineering》浏览原始摘要信息 |
|
点击此处可从《Frontiers of Environmental Science & Engineering》下载全文 |
|