In situ Growth of Zeolite Imidazole Frameworks (ZIF-67) on Carbon Cloth for the Application of Oxygen Reduction Reactions and Microbial Fuel Cells.

Developing high surface area catalysts is an effective strategy to enhance the oxygen reduction reaction (ORR) in the application of microbial fuel cells (MFCs). This can be achieved by developing a catalyst based on metal-organic frameworks (MOFs) because they offer a porous active site for ORR. In this work, a novel in situ growth of 2D shell nanowires of ZIF-67 as a template for N-doped carbon (Co/NC) via a carbonization route was developed to enhance the ORR performance. The effects of different reaction times and different annealing temperatures were studied for a better ORR activity. The growth of the MOF template on the carbon cloth was confirmed using scanning electron microscopy, field emission scanning electron microscopy, transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and Fourier transform infrared. The Co/NC-800 exhibited an enhancement in the ORR activity as evidenced by an onset potential and half-wave potential of 0.0 vs V Ag/AgCl and -0.1 vs V Ag/AgCl, respectively, with a limited current density exceeding the commercial Pt/C. Operating Co/NC-800 on MFC revealed a maximum power density of 30 ± 2.5 mW/m, a maximum current density of 180 ± 2.5 mA/m.