低电位泡沫石墨改性阳极及其在海底微生物燃料电池中的应用

泡沫石墨是一种新型阳极材料, 对其进行改性是提高海底微生物燃料电池性能的重要途径之一。本文研究了混酸改性泡沫石墨阳极及其电化学性能。研究表明:改性后泡沫石墨表面生成羟基、羧基等含氧官能团; 改性阳极接触角降低了24.5°, 润湿性提高, 有利于微生物附着; 交换电流密度达到6760.8 mA/m², 动力学活性提高了53.7倍。研究还发现改性后阳极电位降低了100 mV, 电池开路电位达到865 mV (未改性750 mV), 最大输出功率密度为358.1 mW/m², 提高了2.4倍。三个月放电测试显示, 改性阳极和电池具有相对稳定的性能。同时, 本文初步分析了改性后阳极动力学活性增加和电位降低的原因。该研究结果为构建高输出电压和功率的海底微生物燃料电池提供了依据。

Application of Modified Foam Graphite Anode with Low Potential in Marine Benthic Microbial Fuel Cell

Foam graphite is a novel anode material and its modification is one important way to increase the performance of marine benthic microbial fuel cell. The electrochemical performance of mixed-acid modified foam graphite anode was investigated. The results showed that the hydroxyl and carboxyl groups were introduced on foam graphite surface after modification. The contact angle of modified anode decreased 24.5°, resulting in higher wettability and better attachment for bacteria. Its exchange current density reached 6760.8 mA/m² and the kinetic activity was improved 53.7-fold higher than the original one. Additionally, the present study also found that the anode potential of modified decreased 100 mV, and its open circuit potential reached 865 mV (plain anode 750 mV). The power density of modified cell reached 358.1 mW/m², 2.4-fold higher than unmodified foam. Three months discharge showed that the modified anode and its cell have relatively stable performance. Meanwhile, the paper primarily analyzed the reasons why the anode potential was lower and kinetic activity was higher after modification. The results gave some enlightenments to constructing a novel marine benthic microbial fuel cell with higher output voltage and power.