Composite of medium‐chain‐length polyhydroxyalkanoates‐co‐methyl acrylate and carbon nanotubes as innovative electrodes modifier in microbial fuel cell

Abstract

Abstract A microbial fuel cell is a sustainable and environmental‐friendly device that combines electricity generation and wastewater treatment through metabolic activities of microorganisms. However, low power output from inadequate electron transfer to the anode electrode hampers its practical implementation. Nanocomposites of oxidized carbon nanotubes and medium‐chain‐length polyhydroxyalkanoates (mcl‐PHA) grafted with methyl acrylate monomers enhance the electrochemical function of electrodes in microbial fuel cell. Extensive polymerization of methyl acrylate monomers within mcl‐PHA matrix, and homogenous dispersion of carbon nanotubes within the graft matrix are responsible for the enhancement. Modified electrodes exhibit high conductivities, better redox peak and reduction of cell internal resistance up to 76%. A stable voltage output at almost 700 mV running for 225 H generates maximum power and current density of 351 mW/m 2 and 765 mA/m 2 , respectively. Superior biofilm growth on modified surface is responsible for improved electron transfer to the anode hence stable and elevated power output generation.

Key findings

• ▸The composite modified electrodes exhibit high conductivities and better redox peak.
• ▸The internal cell resistance is reduced by up to 76%.
• ▸The modified electrodes generate a stable voltage output of almost 700 mV for 225 hours, with a maximum power and current density of 351 mW/m² and 765 mA/m², respectively.

Keywords

Identifiers

DOI

10.1002/bab.1928

Journal

Biotechnology and Applied Biochemistry

Year

2020