Evaluation of Low‐Cost Separators for Increased Power Generation in Single Chamber Microbial Fuel Cells with Membrane Electrode Assembly

Abstract

We compared novel size-selective separators, namely the textile fabrics of polyphenylene sulfide (PPS) and sulfonated polyphenylene sulfide (S-PPS), and the nonwoven fabrics of polypropylene80 (PP 80) and PP 100, with commonly used ion exchange separators (Nafion 117 and cation exchange membane-7000; CMI-7000) in terms of power generation, oxygen diffusion, and biofilm formation in a single chamber microbial fuel cell. Size-selective separators exhibited more power generation than ion selective separators. MFC operation with size-selective separators generated power output ranging 0.407 to 0.591 V (1000 Ω), whereas with Nafion it was 0.272 V. In polarization analysis, S-PPS resulted in the highest power density of 190 mW/m 2 , whereas it was 24 mW/m 2 with Nafion-117. Size selective separators showed similar or higher proton conductivity than Nafion 117. Oxygen mass transfer coefficients of size-selective separators (K O = 3.77 .5 10 -5 ) were lower or similar to Nafion (K O = 7.5 10 -5 ).Fourier-transform infrared spectroscopy and scanning electron microscopy analysis revealed that all separators (PP80, S-PPS, and Nafion) contained proteins or carbon chain compounds after 300-day operation, and however, Nafion 117 seems to be more susceptible to biofouling than the other separators.

Tailored Assembly of Molecular Water Oxidation Catalysts on Photoelectrodes for Artificial Photosynthesis

“…[116] Although they showed that PEC performance can be engineered by controlling functional groups on ligand molecules, the use of Nafion is impractical for large scale applications due to its high cost. [117][118][119][120][121] For the immobilization on hydrophobic photoelectrodes or electrodes, hydrophobic polyaromatic functional groups can also be utilized as a surface anchoring group. [122][123][124] However, one can easily expect that this approach would have limited applications, as most artificial photosynthetic reactions are performed in aqueous solutions and that hydrophobic interactions are vulnerable to aggregation or disassembly.…”

Minimum interspatial electrode spacing to optimize air-cathode microbial fuel cell operation with a membrane electrode assembly

“…The specific proton conductivity (S H , S/cm) was determined using ohmic resistance (R oh ,Ω), thickness of the membrane (L m , μm), and working surface area (A, cm 2 ) in the following equation [13,19] Eq. (3)…”

“…In their study, 10-mm electrode spacing exhibited a power density of 284 mW/m 2 , whereas a 30-mm electrode spacing revealed a maximum power density of 229 mW/m 2 . The lower power density for the MFC equipped with a 0 mm spacing (93 mw/m 2 )might be due to a substantial increase in pH at the cathode electrode or due to higher oxygen diffusion from the cathode to the anode due to limited electrogenic activity [19]. Proper interspatial distances (3 and 6 mm) will be helpful for obtaining neutral pH on an air cathode by allowing higher proton transport from the anode to cathode and more OH -diffusion from the cathode to anode [21].…”

“…After a further increase in time (80 days), the cathode potentials decreased to -106 (0 mm), -15 (3 mm), -52 (6 mm), and -21 mV (9 mm), respectively. The negative cathode potentials in the MFC might be due to a limitation in the diffusion of OH -from the cathode to anode, leading to a substantial increase in pH at the cathode electrode [19,21,25]. Moreover, mass transfer losses and biofouling at the cathode increase with operating time, and this can lead to a gradual decrease in cathode potential and decreased cathode catalyst activity [19].…”

Effect of Amino Acid Addition in Marine Sediment on Electrochemical Performance in Microbial Fuel Cells

“…Evidence suggests that the next generation of sustainable energy could come from microorganisms, particularly from anaerobic digestion, and microbial fuel cells (MFCs) are gaining acceptance as an alternative “green” energy technology . Meanwhile, marine sediments microbial fuel cells (MSMFCs) have been used as a renewable power source to remote environmental monitoring , .…”