Exploring the Potential of α-MnO₂/ Carbon Nanotubes for Improved Oxygen Reduction Reaction Performance at the Cathode of Alkaline Fuel Cells

Abstract

In the field of fuel cell technology, the development of cost-effective catalysts is crucial for the commercialization of Alkaline Membrane Fuel Cells (AMFCs). Platinum (Pt) has traditionally been employed as the catalyst in AMFCs, but its high cost poses a major barrier to widespread adoption. In this study, a new catalyst material was developed by incorporating Manganese Dioxide (α-MnO2) into Carbon Nanotubes (CNTs) using hydrothermal synthesis techniques. The synthesized catalyst was characterized using Scanning Electron Microscopy (SEM) and X-ray diffraction (XRD), and its electrocatalytic activity was evaluated through Linear Sweep Voltammetry (LSV) and CV through Rotating Disc Electrode (RDE) experiments. The results showed that the α-MnO2-CNT composite displayed strong durability in the alkaline environment and high electrocatalytic activity for oxygen reduction reaction (ORR). The LSV measurements revealed a current density of -4.1 mA/cm2 and an overpotential of -0.3V relative to Standard Calomel Electrode (SCE) in a 0.1M KOH electrolyte. Additionally, the α-MnO2-CNT composite displayed high methanol tolerance and long-term stability compared to commercial Pt/C catalysts. This study demonstrates that the use of α-MnO2-CNT as a cost-effective alternative to Pt has the potential to facilitate the commercialization of AMFC technology.