A self-charging cyanobacterial supercapacitor

Biosens Bioelectron. 2019 Sep 1:140:111354. doi: 10.1016/j.bios.2019.111354. Epub 2019 May 27.

Abstract

Microliter-scale photosynthetic microbial fuel cells (micro-PMFC) can be the most suitable power source for unattended environmental sensors because the technique can continuously generate electricity from microbial photosynthesis and respiration through day-night cycles, offering a clean and renewable power source with self-sustaining potential. However, the promise of this technology has not been translated into practical applications because of its relatively low performance. By creating an innovative supercapacitive micro-PMFC device with maximized bacterial photoelectrochemical activities in a well-controlled, tightly enclosed micro-chamber, this work established innovative strategies to revolutionize micro-PMFC performance to attain stable high power and current density (38 μW/cm2 and 120 μA/cm2) that then potentially provides a practical and sustainable power supply for the environmental sensing applications. The proposed technique is based on a 3-D double-functional bio-anode concurrently exhibiting bio-electrocatalytic energy harvesting and charge storing. It offers the high-energy harvesting functionality of micro-PMFCs with the high-power operation of an internal supercapacitor for charging and discharging. The performance of the supercapacitive micro-PMFC improved significantly through miniaturizing innovative device architectures and connecting multiple miniature devices in series.

Keywords: Double-functional bio-anodes; Hybrid biodevices; Photosynthetic microbial fuel cells; Self-charging supercapacitors; Supercapacitive energy harvesters.

MeSH terms

  • Bioelectric Energy Sources / microbiology*
  • Biosensing Techniques / instrumentation
  • Cyanobacteria / metabolism*
  • Electric Capacitance
  • Electricity
  • Electrodes
  • Equipment Design
  • Photosynthesis