PGM-Free ORR Catalysts Designed by Templating PANI-Type Polymers Containing Functional Groups with High Affinity to Iron. Issue 7 (1st January 2019)

• Record Type: Journal Article
• Authors: Yin, Xi; Chung, Hoon T.; Martinez, Ulises; Lin, Ling; Artyushkova, Kateryna; Zelenay, Piotr
• Is Part Of: Journal of the Electrochemical Society. Volume 166:Issue 7(2019)
• Page Start: F3240
• Page End: F3245
• Publication Date: 2019-01-01
• Subjects: Electrocatalysis -- iron -- oxygen reduction reaction -- PGM-free catalysts; Electrochemistry -- Periodicals; 541.3705
• DOI: 10.1149/2.0301907jes
• Languages: English
• ISSNs: 0013-4651

Abstract

Abstract : In this work, a coordination-chemistry approach was used to increase the content of nitrogen-coordinated iron moieties (Fe-Nx ) in platinum group metal-free (PGM-free) catalysts for oxygen reduction reaction (ORR). The catalysts were derived from a series of polyaniline (PANI)-type precursors with N-containing functional side chains having high affinity to iron. The PGM-free ORR catalysts synthesized using such polymeric templates were characterized by scanning electron microscopy, X-ray diffractometry, and tested in an electrochemical cell and H2 -air fuel cell for ORR activity. X-ray photoelectron spectroscopy (XPS) analysis showed that, in spite of similar nitrogen contents, catalysts obtained using PANI-type polymers containing side chains with high affinity to iron had higher Fe content than PANI-derived catalyst. These PGM-free catalysts showed improved ORR activity in an electrochemical cell and in H2 -air fuel cell testing, compared to the PANI-derived catalyst. A correlation between the content of Fe-Nx moieties and the fuel cell performance was observed in these PGM-free ORR catalysts.