結合微生物燃料電池與光電化學電池探討其自由基產生機制

Abstract

隨著科技的快速發展與人口數量的增長，全球對於水資源與能源的需求日益上升，導致環境中的水體受到大量有機物、重金屬和其他有害物質的污染，造成嚴重的環境污染問題。傳統水處理技術普遍存在能耗高、操作成本高及處理效率有限等缺點，因此開發兼具污染物降解與能源回收之綠色能源技術，成為當前各國關注的研究議題。 微生物燃料電池( Microbial Fuel Cell, MFC )是一種結合廢水處理與產生電能的技術，利用產電菌在厭氧的環境下分解有機物物並產生電子，電子再透過外部電路產生電流；光電化學電池( Photoelectrochemical Cell, PEC )則透過太陽光照射於半導體材料以產生電子－電洞對，進一步生成活性氧化物( Reactive Oxygen Species, ROS )以降解污染物，或經由水解反應產生氫氣。然而，MFC與PEC系統各自存在技術上的限制與缺點，因此本研究嘗試將這兩種系統進行結合，以減少其單獨運行時的限制，並進一步探討其自由基產生機制。 本研究以台北市迪化污水廠之厭氧污泥作為MFC之微生物來源，並採用H-type雙槽式反應槽進行MFC與PEC系統建構。整體研究分為三個階段：第一階段為MFC系統之產電菌馴養；第二階段進行α-Fe2O3光電極之合成與表面特性分析；第三階段將MFC與PEC系統進行整合，並於不同曝氣與光照條件下，探討其對自由基產生的影響，藉此釐清操作條件與自由基生成之關聯性，以作為未來污水處理應用與系統設計之參考依據。 研究結果顯示，光照條件可做為驅動PEC反應之重要因素；而在避光與照光條件下，相較於單一PEC系統，MFC-PEC系統所產生之·OH與雙氧水濃度皆更高，由此證實MFC所提供之電子對自由基與雙氧水的產生也有幫助。本研究證實MFC與PEC系統之整合可有效提升自由基與雙氧水的產生表現，顯示其應用於水污染整治之可行性與潛力，有望作為未來永續水處理技術之發展方向。

With rapid technological advancement and population growth, global demand for water and energy has significantly increased, resulting in severe environmental pollution issues, including contamination by organic pollutants, heavy metals, and other hazardous substances in water bodies. Traditional wastewater treatment technologies often suffer from high energy consumption, elevated operational costs, and limited treatment efficiency. Thus, the development of green technologies capable of simultaneously degrading pollutants and recovering energy has become an important research topic worldwide. Microbial fuel cell (MFC) integrates wastewater treatment and electricity generation by utilizing electrochemically active bacteria that anaerobically degrade organic matter and generate electrons, which flow through an external circuit to produce electricity. Photoelectrochemical cell (PEC), another promising technology, uses solar irradiation on semiconductor materials to generate electron–hole pairs, leading to the formation of reactive oxygen species (ROS) for pollutant degradation and enabling hydrogen production via photocatalytic water splitting. However, both MFC and PEC systems individually face technical limitations. To address these limitations, this study integrates MFC and PEC systems to explore the mechanisms of radical generation under different operational conditions, aiming to evaluate their synergistic potential in sustainable wastewater treatment. In this study, anaerobic sludge was collected from Dihua Wastewater Treatment Plant in Taipei City and used as the microorganism source. Both MFC and PEC systems were constructed using H-type dual-chamber reactors. The research comprised three stages: the first stage involved the cultivation and acclimation of electroactive bacteria in the MFC; the second stage involved the synthesis and surface characterization of α-Fe₂O₃ photoelectrodes; and the third stage focused on integrating MFC and PEC systems under different aeration and illumination conditions, to explore their influence on radical generation, thereby elucidating the correlation between operational parameters and radical production. The results provide valuable insights and guidelines for future wastewater treatment applications and system design. Experimental results demonstrated that illumination significantly promotes radical generation, indicating that it is an essential factor for driving PEC reactions. Under both dark and illuminated conditions, the integrated MFC-PEC system showed higher steady-state concentrations of •OH and H2O2 compared to the PEC system alone, confirming that electrons supplied from the MFC promotes radical production. Overall, this study confirmed that integrating MFC and PEC systems effectively enhances radical and H2O2 generation performance, highlighting the feasibility and potential of this integrated system for water pollution remediation for developing sustainable wastewater treatment technologies.