铁酸锰活性炭阴极催化剂的制备与对微生物燃料电池产电性能的影响

Preparation of manganese ferrite activated carbon cathode catalyst and its effect on the electricity generation performance of microbial fuel cells

微生物燃料电池(microbial fuel cell,MFC)阴极的氧化还原反应能力对MFC的产电性能起着至关重要的作用,因此,本研究制备了铁酸锰/活性炭(MnFe_(2)O_(4)/AC)并对其进行材料学表征,研究其作为MFC空气阴极催化剂时产电和污水处理效果.研究表明,MnFe_(2)O_(4)和AC物质的量比为1:3时MFC电功率密度最高,达302.7mW/m^(2).在峰值电压附近维持时间长达200h,维持时间是传统Pt/C催化剂MFC的4倍,库伦效率达到17.45%.在催化剂重复利用实验中发现,在相同的运行时间内,采用Pt/C催化剂的MFC电压下降明显,而采用MnFe_(2)O_(4)/AC催化剂的MFC电压基本保持稳定,证明了MnFe_(2)O_(4)/AC催化剂良好的循环稳定性.污水处理效果方面,MnFe_(2)O_(4)和AC物质的量比为1:3时处理效果最好,COD去除率达74.66%.因此,MnFe_(2)O_(4)/AC催化剂制备简单、价格低廉、电化学性能稳定,在提高MFC产电持久性方面具有实际意义.

The oxidation reduction reaction capability of the microbial fuel cell(microbial fuel cell,MFC)cathode plays a vital role in power generation of MFC.In this study,manganese ferrite/activated carbon(MnFe_(2)O_(4)/AC)was prepared and characterized by material science,and it was used as the cathode catalyst of MFC to explore its effects on electricity generation and sewage treatment of MFC.Results demonstrated that when the molarratio of MnFe_(2)O_(4) to AC was 1:3,the power density of MFC was the highest,reaching 302.7mW/m^(2).The maintenance time near the peak voltage was up to 200h,which was 4times that of the traditional MFC using Pt/C as the catalyst,and the coulombic efficiency reached 17.45%.Moreover,in the reusability test of catalyst,the voltage of the MFC using the Pt/C catalyst dropped significantly,while the voltage of the MFC using the MnFe_(2)O_(4)/AC catalyst remained basically stable during the same running time indicating good cycle stability of the MnFe_(2)O_(4)/AC catalyst.In terms of sewage treatment effect,the highest treatment efficiency was 74.66%when the molar ratio of MnFe_(2)O_(4)/AC was 1:3.Therefore,the MnFe_(2)O_(4)/AC catalyst is simple to prepare,low in price,and stable in electrochemical performance,which has practical significance in improving the durability of MFC power generation.