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《Iron-rich nanoparticle encapsulated, nitrogen doped porous carbon materials as efficient cathode electrocatalyst for microbial fuel cells》

  • 来源专题：广州能源研究所信息监测
  • 编译者： giecinfo
  • 发布时间：2016-03-24

  • Developing efficient, readily available, and sustainable electrocatalysts for oxygen reduction reaction (ORR) in neutral medium is of great importance to practical applications of microbial fuel cells (MFCs). Herein, a porous nitrogen-doped carbon material with encapsulated Fe-based nanoparticles (Fe-Nx/C) has been developed and utilized as an efficient ORR catalyst in MFCs. The material was obtained through pyrolysis of a highly porous organic polymer containing iron(II) porphyrins. The characterizations of morphology, crystalline structure and elemental composition reveal that Fe-Nx/C consists of well-dispersed Fe-based nanoparticles coated by N-doped graphitic carbon layer. ORR catalytic performance of Fe-Nx/C has been evaluated through cyclic voltammetry and rotating ring-disk electrode measurements, and its application as a cathode electrocatalyst in an air-cathode single-chamber MFC has been investigated. Fe-Nx/C exhibits comparable or better performance in MFCs than 20% Pt/C, displaying higher cell voltage (601 mV vs. 591 mV), maximum power density (1227 mW m−2 vs. 1031 mW m−2) and Coulombic efficiency (50% vs. 31%). These findings indicate that Fe-Nx/C is more tolerant and durable than Pt/C in a system with bacteria metabolism and thus holds great potential for practical MFC applications.

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    • 编译者：张宗鹏
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    • 来源专题：现代化工
    • 编译者：武春亮
    • 发布时间：2024-06-05
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