The green exfoliation of graphite waste and its suitability for biosensor applications

This work is concerned with the bio-exfoliation of graphite using a soil bacterium. The isolated bacterium showed a detectable ability to oxidize and change its physical appearance and chemical structure. Multiple characterization procedures were used to study the physical and chemical changes. Raman and FTIR spectroscopy proved that the isolate G3 partially exfoliated the graphite into multi-layer sp(2) graphitic layers. Scanning electron microscopy (SEM) proved that there was a change in morphology between untreated graphite waste and that manipulated by bacteria. Cyclic voltammetry results proved that the green exfoliated graphite (GEG) was suitable for use in biosensor applications and showed a noticeable ability to detect methanol, even at lower concentrations. These findings are considered as promising for the biological manipulation of graphite waste for environmental purposes. In addition, it is proved that the bacterial transformation of graphite into other GEG structures occurs without needing the chemically hazardous methods that are currently applied.