Yang Ting-ting, Zhu Neng-wu, Lu Yu, Wu Ping-xiao
Huan Jing Ke Xue. 2016 Jan 15;37(1):350-8.
The cathode catalyst plays an important role in the electricity generation of microbial fuel cells (MFCs). In order to achieve the large-scale application of MFCs, cathode catalyst with low cost and high oxygen reduction reaction (ORR) has great sense to substitute the precious catalyst of Pt/C. Here chemical vapor deposition (CVD) method was utilized accompanied with melamine as a nitrogen and carbon precursor, oxidized carbon powder (Black Pearls 2000 or Acetylene Black) as carbon precursor and iron acetate as an iron precursor so as to synthesize two kinds of Fe and nitrogen doped carbon nanotube/nanoparticle composites (FeNCB and FeNCC) as MFCs cathode catalysts. The cyclic voltammetry and rotating ring-disk electrode were applied to analyze the ORR activity discrepancies of FeNCB, FeNCC, and Pt/C (20%), which was confirmed by MFC operation. The results showed that the ORR performance of FeNCB was slightly better than Pt/C and dramatically better than FeNCC. Moreover, the catalysis of ORR by FeNCB was through a four-electron transfer pathway. Besides, the performance of MFC-FeNCB was higher than MFC-Pt/C and observably higher than MFC-FeNCC which was a contribute to promote the scale of MFC. MFC-FeNCB achieved the maximum power output density of 1212.8 mW x m(-2), an open circuit potential of 0.875 V, and a stabilized voltage of (0.500 +/- 0.025) V. Further analysis via X-ray diffraction, X ray photoelectron spectroscopy, and Raman exhibited that the diameter of carbon nanotube, the types of N and Fe as well as the concentration of nitrogen, iron and oxygen was the reason for the discrepancies of ORR characteristics for the prepared catalysts.
阴极催化剂在微生物燃料电池（MFC）发电过程中起着重要作用。为实现MFC的大规模应用，采用低成本且具有高氧还原反应（ORR）性能的阴极催化剂替代Pt/C贵金属催化剂具有重要意义。本文利用化学气相沉积（CVD）法，以三聚氰胺作为氮和碳前驱体、氧化炭粉（黑珍珠2000或乙炔黑）作为碳前驱体、醋酸铁作为铁前驱体，合成了两种Fe和N掺杂的碳纳米管/纳米颗粒复合材料（FeNCB和FeNCC）作为MFC的阴极催化剂。采用循环伏安法和旋转环盘电极分析了FeNCB、FeNCC和Pt/C（20%）的ORR活性差异，并通过MFC运行进行了验证。结果表明，FeNCB的ORR性能略优于Pt/C，且显著优于FeNCC。此外，FeNCB对ORR的催化作用是通过四电子转移途径实现的。另外，MFC-FeNCB的性能高于MFC-Pt/C，且明显高于MFC-FeNCC，这有助于推动MFC的规模化发展。MFC-FeNCB实现了1212.8 mW·m⁻²的最大功率输出密度、0.875 V的开路电位以及（0.500±0.025）V的稳定电压。通过X射线衍射、X射线光电子能谱和拉曼光谱进一步分析表明，碳纳米管的直径、N和Fe的种类以及氮、铁和氧的浓度是所制备催化剂ORR特性存在差异的原因。
