Development of Electrocatalyst for Anion-type Polymer Electrolyte Fuel Cell using KOH-doped Polybenzimidazole

摘要

Anion-exchange membrane fuel cells (AEMFC) are emerged as a alternative technology to overcome technical and cost issues of proton-exchange membrane fuel cells (PEMFC). In the present study, we describe a new electrocatalyst for AEMFC composed of carbon nanotubes (CNTs), KOH-doped polybenzimidazole (PBI) and platinum nanoparticles (Pt), in which CNTs are wrapped by KOH-doped PBI in nanometer thickness and Pt are efficiently loaded on the wrapping layer. In the electrocatalyst, it is revealed that CNTs and KOH-doped PBI layer functions as electron- and hydroxide-conductive path, respectively, and large exposed surface of Pt are allows an effective access of the fuel gas. Membrane electrode assembly fabricated with the electrocatalyst shows a high power density of 256 mW cm-2. To the best of our knowledge, this is the highest value in the AEMFC system measured in a similar experimental condition.