Reduction of palladium and production of nano-catalyst by Geobacter sulfurreducens

Appl Microbiol Biotechnol. 2013 Nov;97(21):9553-60. doi: 10.1007/s00253-012-4640-9. Epub 2012 Dec 28.

Abstract

The present study is the first report on the ability of Geobacter sulfurreducens PCA to reduce Pd(II) and produce Pd(0) nano-catalyst, using acetate as electron donor at neutral pH (7.0 ± 0.1) and 30 °C. The microbial production of Pd(0) nanoparticles (NPs) was greatly enhanced by the presence of the redox mediator, anthraquinone-2,6-disulfonate (AQDS) when compared with controls lacking AQDS and cell-free controls. A cell dry weight (CDW) concentration of 800 mg/L provided a larger surface area for Pd(0) NPs deposition than a CDW concentration of 400 mg/L. Sample analysis by transmission electron microscopy revealed the formation of extracellular Pd(0) NPs ranging from 5 to 15 nm and X-ray diffraction confirmed the Pd(0) nature of the nano-catalyst produced. The present findings open the possibility for a new alternative to synthesize Pd(0) nano-catalyst and the potential application for microbial metal recovery from metal-containing waste streams.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acetates / metabolism
  • Anthraquinones / metabolism
  • Geobacter / metabolism*
  • Hydrogen-Ion Concentration
  • Microscopy, Electron, Transmission
  • Nanoparticles / metabolism
  • Nanoparticles / ultrastructure
  • Oxidation-Reduction
  • Palladium / metabolism*
  • Temperature
  • X-Ray Diffraction

Substances

  • Acetates
  • Anthraquinones
  • anthraquinone-2,6-disulfonate
  • Palladium