S. Pedireddy, M.K. Ravva, C. Nayak, D. Anjum, S.N. Jha, P.E. Saikaly
Single-atom catalysts, Water splitting, Electrocatalyst, Bifunctional electrocatalyst, Hydrogen evolution reaction, Oxygen evolution reaction, Geobacter sulfurreducens, Extracellular electron transfer
Here, we report a reproducible method for the synthesis of SA-Ms on the surface of the electroactive bacterium, Geobacter sulfurreducens (GS). Our approach is based on the extracellular electron transfer capability of GS to reduce extracellular metal ions by harvesting the metabolically formed electrons inside the cell. The formation of SA-Ms on the surface of GS was achieved by creating an MN3 moiety (where M=Ir, Pt, Co, Ru, Cu, and Pd, and N = nitrogen), identified by X-ray absorption fine structure analysis. Interestingly, our bio-derived SA-M@GS can be directly used as OER and HER electrocatalysts upon drying without further heat treatments such as pyrolysis or hydrothermal approaches.