Fe-Doped Copolymer-Templated Nitrogen-Rich Carbon as a PGM-Free Fuel Cell Catalyst

Platinum group metal-free (PGM-free) catalysts present a promising opportunity to make hydrogen fuel cells more affordable; however, issues with stability and electrochemical activity continue to hinder their application. Recent studies point to the availability of nitrogen and a controlled mesoporous structure as avenues of improvement. To address this need, copolymer-templated nitrogen-enriched carbon (CTNC) was used as the precursor to prepare PGM-free catalysts for the oxygen reduction reaction (ORR). By employing its rich nitrogen content and interconnected mesoporous structure, a significant amount of Fe-N-C-active sites were formed by co-annealing CTNC with FeSO4. The formed N/Fe co-doped nanocarbon (CTNC-Fe) catalyst exhibits good electrochemical activity with a half-wave potential of 0.781 V vs normal hydrogen electrode (NHE), a total surface area of 400 m(2)/g, and a power density of 180 mW/cm(2). The block copolymer (BCP) was made by atom transfer radical polymerization (ATRP), which allows control and tunability of the block copolymer. This work opens new opportunities to improve the electrochemical activity and stability of PGM-free catalysts by controlled polymerization techniques that precisely tune the pore structure and maximize nitrogen content to improve the formation of active sites in the catalysts.