Hydrazine hydrate chemical reduction as an effective anode modification method to improve the performance of microbial fuel cells

Abstract

Abstract Background The anode material is considered a key factor influencing the energy conversion in microbial fuel cells ( MFCs ) because it links microbiology and electrochemistry. To further improve power generation, carbon mesh anodes modified by hydrazine hydrate chemical reduction were applied in air‐cathode MFCs . Results The power densities of MFCs using hydrazine‐treated anodes were all higher than the untreated control, among which a 30% hydrazine hydrate‐modified anode ( CM ‐30%) showed the best performance. The maximum power density reached 865 mW m −2 , which was 31% higher than the unmodified control ( CM ‐0%, 662 mW m −2 ). The Coulombic efficiency ( CE ) increased from 10.7% to 13.3% (improved by 24.3%). Furthermore, the acclimation time was reduced from 142 h to 95 h, shortened by 32% compared with the control. Such improvement in MFCs performance was correlated with the increased surface area revealed by scanning electron microscope ( SEM ) and the change of surface functional groups revealed by X‐ray photoelectron spectroscopy ( XPS ) analysis. This enhancement in MFCs performance was also proved feasible when using real swine wastewater as substrate . Conclusions The results indicated that hydrazine hydrate chemical reduction was an effective method for anode modification to improve the performance of MFCs . © 2013 Society of Chemical Industry

Key findings

• ▸Power densities of MFCs using hydrazine-treated anodes were higher than untreated controls.
• ▸A 30% hydrazine hydrate-modified anode showed the best performance.
• ▸Maximum power density reached 865 mW/m², 31% higher than unmodified control.

Keywords

Identifiers

DOI

10.1002/jctb.4074

Journal

Journal of Chemical Technology & Biotechnology

Year

2013