Toward Escherichia coli bacteria machine for water oxidation
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Nature uses a Mn oxide-based catalyst for water oxidation in plants, algae, and cyanobacteria. Mn oxides are among major candidates to be used as water-oxidizing catalysts. Herein, we used two straightforward and promising methods to form Escherichia coli bacteria/Mn oxide compounds. In one of the methods, the bacteria template was intact after the reaction. The catalysts were characterized by X-ray photoelectron spectroscopy, visible spectroscopy, scanning electron microscopy, high-resolution transmission electron microscopy, diffuse reflectance infrared Fourier transform spectroscopy, Raman spectroscopy, and X-ray diffraction spectrometry. Electrochemical properties of the catalysts were studied, and attributed redox potentials were assigned. The water oxidation of the compounds was examined under electrochemical condition. Linear sweep voltammetry showed that the onsets of water oxidation in our experimental condition for bacteria and Escherichia coli bacteria/Mn oxide were 1.68 and 1.56 V versus the normal hydrogen electrode (NHE), respectively. Thus, the presence of Mn oxide in the catalyst significantly decreased (~ 120 mV) the overpotential needed for water oxidation.
KeywordsBacteria Catalyst Hydrogen Manganese oxide Water oxidation
The authors are grateful to the Institute for Advanced Studies in Basic Sciences and Iran National Science Foundation for the financial support. The reported study was funded by grant RFBR-Iran according to the joint research Project Nos. 17-54-560012, 96003636 supported by Russian Foundation for Basic Research and by Iran National Science Foundation (INSF).
- Ahmad J, Dickerson MB, Cai Y, Jones SE, Ernst EM, Vernon JP, Haluska MS, Fang Y, Wang J, Subramanyam G, Naik RR, Sandhage KH (2008) Rapid bioenabled formation of ferroelectric BaTiO3 at room temperature from an aqueous salt solution at near neutral pH. J Am Chem Soc 130:4–5CrossRefPubMedGoogle Scholar
- Glikman TS, Shcheglova IS (1968) Water oxidation by Mn oxide. Kinet Katal 9:461–470Google Scholar
- Levinson W (2008) Review of medical microbiology and immunology, 10th edn. McGraw-Hill Companies. Inc., New YorkGoogle Scholar
- Simon DE, Morton RW, Gislason JJ (2004) A close look at electrolytic manganese dioxide (EMD) and the γ-MnO2 & ε-MnO2 phases using Rietveld modeling. Adv X Ray Anal 47:267–280Google Scholar
- Suresh S, Mortensen A (1998) Fundamentals of functionally graded materials: processing and thermomechanical behavior of graded metals and metal-ceramic composites. IOM Communications Ltd, London, p 168Google Scholar
- Yeston J (2017) Three strands ironed closely together. Science 355:143–145Google Scholar