本實驗探討串聯微生物燃料電池(Microbial Fuel Cells，MFC)的表現最佳化，使用250 ml糖蜜(Molasses)當作陽極燃料的基底，用海水將其混合，找出混合的最佳比例為1:1，在此比例下添加0.5 M碳酸氫鈉(NaHCO3)，陰極使用海水250 ml，電極使用備長碳棒(charcoal)，而隔離膜(separator membrane)使用蛋殼膜(eggshell membrane)的情況下各單顆MFC有最好的產電表現。
將最佳比例兩組的MFC串聯，串聯之後的輸出電壓約為單顆的3倍、跨電容的電壓提高30%、直流電流提高40%、位移電流提高40%，經過串聯可以使本來不穩定的MFC輸出電力數值接近穩定，而起到增加電池可靠性的作用，並將從儲存電能之360 F電容之跨電壓微分所得到的位移電流(displacement current)做快速傅立葉轉換(Fast Fourier Transform, FFT)，以偵測出電容得到和失去電子過程的反應頻率，實驗結果證明MFC中細菌的氧化還原反應(redox reaction)頻率主要發生在0.2~0.3 Hz，同時數據顯示算出來的位移電流比直接用電錶量測的輸出電流對MFC的即時偵測有更高的可靠性與相關性。
關於電化學的反應參數對MFC性能的影響研究，實驗數值顯示陽極氧化反應受到反應物(燃料)的pH值的影響最大，而量測燃料添加NaHCO3之後的鹽度值，顯示出陽極液pH值增加的幅度和鹽度有關聯性， MFC的產電效率可由陽極液的氧化後電導度值增加與陰極液的初始電導度值做依據，陰極液的溶氧值變化可看出在陰極溶液中細菌還原反應消耗氧的程度，而從陰極液中碳酸鹽硬度的變化顯示出陽極液反應後產生CO2氣體並經由陽極槽電極上之孔洞提供給陰極液以減緩陰極液之pH值增加並降低MFC兩極間經氧化還原反應後各自的pH值差異以增進MFC效能。

In this research, the performance optimization of Microbial Fuel Cells in series was discussed. Molasses was used as the anodic fuel substrate, mixing it with seawater. The optimal mixing ratio was found to be 1:1. At this ratio, 0.5 M sodium bicarbonate (NaHCO3) was added to anolyte, 250 ml seawater was used for the catholyte, a charcoal rod was used for the electrode, and an eggshell membrane was used for the separators. A single MFC had the best power performance on this condition.
Connecting two MFC with the best condition in series. The output voltage is about three times larger than the single, the voltage across the capacitor is increased by 30%, the DC current is increased by 40%, and the displacement current is increased by 40%. Connecting in series can make the originally unstable MFC electrical properties are close to stable, and play a role in increasing the reliability of the MFC. The displacement current can be obtained from the differential voltage across the 360 F capacitor with Fast Fourier Transform (FFT) to detect the response frequency of the capacitor gaining and losing electrons. The experimental results show that 0.2~0.3 Hz is the majority frequency of bacterial redox reaction in the MFC, and the data show that the calculated displacement current has higher reliability and relevance for the real-time detection of MFC than the output current measured by the ammeter.
Regarding the effects of electrochemical reaction parameters on the performance of MFC, the experimental results show that the anodic oxidation reaction is most affected by the pH value of the reactant (fuel), and measurement of the salinity value of the anolyte after adding NaHCO3 shows that the increase of the pH value of the anolyte is related to the salinity. The power generation efficiency of MFC can be estimated by the increase in the conductivity value of the oxidation anolyte and the initial conductivity value of the catholyte. The change of the dissolved oxygen value of the catholyte can show the degree of oxygen consumption by the bacterial reaction in the catholyte. The change of carbonate hardness in the catholyte shows that CO2 biogas is generated by the anolyte reaction, and the biogas is supplied to the catholyte through the channel on the anodic electrode to slow down the increase of the pH value of the catholyte and reduce the pH value difference between the two electrolyte to improve the efficiency of the MFC.

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