Improvement of Yeast−Biofuel Cell Output by Electrode Modifications

Abstract

In this study, a methodology for electrodeposition of nickel nanostructures on carbon felt was developed on the base of pulse plating technique. Different in size, shape, and distribution, Ni-island nanostructures were deposited varying the potential, current, pulse duration, and cycle reiteration. The biocompatibility and nontoxicity of the newly created materials toward Candida melibiosica yeast cells was proven. The prepared Ni-nanomodified carbon felts were investigated as anodes in a two-chamber mediatorless yeast−biofuel cell. Maximum power density values of 720 and 390 mW/m2 were achieved with the electrodes modified under galvanostatic and potentiostatic conditions, respectively, against 36 mW/m2 for the nonmodified ones. The better biofuel cell performance obtained with the Ni-modified electrodes is assigned to an improved electron transfer.

Surface Modification for Enhanced Biofilm Formation and Electron Transport in Shewanella Anodes

“…2 Modification techniques include surface treatments with physical or chemical methods, immobilization of conductive and electroactive polymers, as well as deposition of various metals or metal seeds. 3,[7][8]19 In addition, surface chemical or electrochemical oxidation can also be an effective treatment method for enhanced bacteria-electrode interactions. 9 Surface chemistry modification techniques such as benzene diazonium treatment 20 and ammonia gas treatment 20 provide a positively charged electrode surface, which as been speculated to be beneficial for bacterial attachment.…”

“…2 Therefore, electrode design is one of the greatest challenges in making MFCs a cost-effective and scalable technology. [3][4][5][6][7][8] Among the general requirements, such as good conductivity, chemical stability, mechanical strength, high surface area and low cost, anode materials should posses several key characteristics that will determine the rate of bacteria-electrode interactions. These are, but not limited to: i) high surface roughness; ii) biocompatibility; and iii) surface chemistry that enhances bacterial attachment and electron transfer.…”

Yeast as a Biocatalyst in Microbial Fuel Cell

“…The authors related the improvement in the performance to same reasons that were described above [55].…”

“…The performance of C. melibiosica-based MFC was investigated using modified and nonmodified (NME) carbon felt [55]. The carbon felt was modified by Ni using two different techniques, i.e., galvanostatic pulse (GME) and potentiostatic pulse (PME).…”

“…Several yeast strains have been studied as biocatalysts in MFC with or without external mediator such as Saccharomyces cerevisiae (S. cerevisiae) [41][42][43][44][45][46][47][48][49][50][51][52], Candida melibiosica 2491 (C. melibiosica) [53][54][55][56], Hansenula anomala (H. anomala) [40], Hansenula polymorpha (Hansenula polymorpha) [57], Arxula adeninivorans (A. adeninivorans) [58] and Kluyveromyces marxianus (K. marxianus) [59].…”