Synthesizing and optimizing Manganese dioxide nanotube catalyst for oxygen reduction reaction in polymer electrolyte membrane fuel cell

A. Ullah, M. Humayun, M. Arif
University Engineering and Technology Peshawar,
Pakistan

Keywords: polymer electrolyte membrane fuel cell, PEMFC, oxygen reduction reaction, nanotubes

Summary:

A variety of highly active pristine catalysts manganese dioxide (α-MOx) was synthesized by hydrothermal technique and annealed at different temperature (α-MO300, α-MO400 and α-MO500), converting them into nanotubes in nitrogen atmosphere. Nitrogen was inadvertently doped to the manganese oxide nanotubes. The catalysts were further characterized by scanning electron microscope (SEM), X-ray diffraction (XRD), Brunauer–Emmet–Teller (BET) method and catalyst activity has been calculated by Rotating Disc Electrode (RDE) experiment. The state of the art technique is proved efficacious for the improvised nitrogen doped α-MOx nanotubes. The resulting materials are remarkably stronger in alkaline environment during experimental conditions and have high electro catalytic activity for oxygen reduction reaction (ORR). The α-MO400 nanotubes even outshine the commercial Pt/C by catalytic activity having higher current density. Of these, alpha manganese oxide at 400 oC (α-MO400) catalyst was the most active catalyst for ORR with a half wave potential of -0.3V having a current density of -6.5 mA/cm2 and an onset at -0.2V versus SCE.