Fabrication of macroporous chitosan scaffolds doped with carbon nanotubes and their characterization in microbial fuel cell operation

Hawaii Natural Energy Institute, University of Hawaii, Honolulu, HI 96822, USA.
Enzyme and Microbial Technology (Impact Factor: 2.32). 05/2011; 48(6-7):458-65. DOI: 10.1016/j.enzmictec.2011.02.006
Source: PubMed

ABSTRACT Chitosan (CHIT) scaffolds doped with multi-walled carbon nanotubes (CNT) were fabricated and evaluated for their utility as a microbial fuel cell (MFC) anodic material. High resolution microscopy verified the ability of Shewanella oneidensis MR-1 to directly colonize CHIT-CNT scaffolds. Cross-linking agents 1-ethyl-3-[3-dimethylaminopropyl] carbodimide hydrochloride (EDC), glutaraldehyde and glyoxal were independently studied for their ability to strengthen the CHIT-CNT matrix without disrupting the final pore structure. 2.5 vol% glyoxal was found to be the optimal cross-linker in terms of porosity (BET surface area=30.2 m(2) g(-1)) and structural stability. Glyoxyl and EDC cross-linked CHIT-CNT scaffolds were then studied for their ability to transfer electrons to underlying glassy carbon. Results showed an open circuit cell voltage of 600 mV and a maximum power density of 4.75 W/m(3) at a current density of 16 A/m(3) was achieved in non stirred batch mode, which compares well with published data using carbon felt electrodes where a power density of 3.5 W/m(3) at a current density of 7 A/m(3) have been reported. Additionally, CHIT-CNT scaffolds were impregnated into carbon felt electrodes and these results suggest that CHIT-CNT scaffolds can be successfully integrated with multiple support materials to create hybrid electrode materials. Further, preliminary tests indicate that the integrated scaffolds offer a robust macroporous electrode material that can be used in flow-through configurations.

Download full-text


Available from: Shelley Minteer, Feb 04, 2014
87 Reads
  • Source
    • "rication of electrodes by using nanotechnology can provide new dimensions in MFC science (Higgins et al., 2011; Liang et al., 2010; Sharma et al., 2008). Previous studies have reported results with electrodes coated with nanoparticles. "
    [Show abstract] [Hide abstract]
    ABSTRACT: Microbial fuel cells (MFCs) have applications possibilities for wastewater treatment, biotransformation, and biosensor, but the development of highly efficient electrode materials is critical for enhancing the power generation. Two types of electrodes modified with nanoparticles or grass-like nanostructure (termed nanograss) were used. A two-chamber MFC with plain silicium electrodes achieved a maximum power density of 0.002mW/m(2), while an electrode with nanograss of titanium and gold deposited on one side gave a maximum power density of 2.5mW/m(2). Deposition of titanium and gold on both sides of plain silicium showed a maximum power density of 86.0mW/m(2). Further expanding the surface area of carbon-paper electrodes with gold nanoparticles resulted in a maximum stable power density of 346.9mW/m(2) which is 2.9 times higher than that achieved with conventional carbon-paper. These results show that fabrication of electrodes with nanograss could be an efficient way to increase the power generation.
    Bioresource Technology 07/2012; 123:177-83. DOI:10.1016/j.biortech.2012.07.048 · 4.49 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: A hybrid lactate/air biofuel cell has been created using a microbial anode with Shewanella MR1 integrated into a chitosan–carbon nanotube porous matrix and a DET-based laccase air-breathing cathode. Open circuit potentials of 1 V and power densities of 26 W/m3 are reported. A stable 5-day galvanostatic polarization shows a loss of only 4% of potential.
    ACS Catalysis 07/2011; 1(9):994–997. DOI:10.1021/cs2003142 · 9.31 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: This research introduces a method for fabrication of conductive electrode materials with hierarchical structure from porous polymer/carbon composite materials. We describe the fabrication of (3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) scaffolds doped with carbon materials that provide a conductive three-dimensional architecture that was demonstrated for application in microbial fuel cell (MFC) anodes. Composite electrodes from PHBV were fabricated to defined dimensions by solvent casting and particulate leaching of a size-specific porogen (in this case, sucrose). The cellular biocompatibility of the resulting composite material facilitated effective immobilization of a defined preparation of Shewanella oneidensis DSP-10 as a model microbial catalyst. Bacterial cells were immobilized via chemical vapor deposition (CVD) of silica to create an engineered biofilm that exhibits efficient bioelectrocatalysis of a simple-carbon fuel in a MFC. The functionalized PHBV electrodes demonstrate stable and reproducible anodic open circuit potentials of -320 ± 20 mV (vs Ag/AgCl) with lactate as the electron donor. Maximum power densities achieved by the hierarchically structured electrodes (~5 mW cm(3)) were significantly higher than previously observed for graphite-felt electrodes. The methodology for fabrication of scalable electrode materials may be amenable to other bioelectrochemical applications, such as enzyme fuel cells and biosensors, and could easily be adapted to various design concepts.
    ACS Applied Materials & Interfaces 03/2012; 4(4):2082-7. DOI:10.1021/am300048v · 6.72 Impact Factor
Show more