02706nas a2200265   4500008004100000022001400041245013400055210006900189260000900258300001400267490000700281520178300288653001802071653002002089653001402109653002102123653001702144653002002161653002202181653003002203100002802233700002402261700002402285856013102309       2021                        eng d  a1944-824400aToward pH independent oxygen reduction reaction by polydopamine derived 3D interconnected, iron carbide embedded graphitic carbon0 aToward pH independent oxygen reduction reaction by polydopamine   cFEB   a8147-81580 v133 a<p>Recent advancements on the development of nonprecious electrocatalysts with iron (Fe) incorporated active centers have generated confidence on realizing cost-effective proton exchange membrane fuel cells (PEMFCs). However, most of these catalysts that emerged as a substitution for the platinum supported on carbon (Pt/C) catalysts in oxygen reduction reaction (ORR) are active under basic conditions, and their feasibility in PEMFCs remains as a challenge. In this scenario, this work reports the synthesis of a Pt-free oxygen reduction electrocatalyst prepared by the annealing of polydopamine grown melamine foam. The prepared catalyst has a three-dimensional (3D) interconnected bilayer network structure possessing the carbon nitride backbone wrapped by graphitic carbon layer bearing iron carbides and nitrides as the active centers (3DFePDC). Interestingly, the 3D-FePDC catalyst displayed an ORR activity both under acidic and basic conditions. Whereas the ORR performance of 3D-FePDC closely matches that of the commercial Pt/C in the basic medium, it displays only a low overpotential value of 60 mV under acidic conditions compared to its Pt counterpart. The kinetics of ORR on 3DFePDC is found to be similar to the four-electron (4e) reduction pathway displayed by Pt/C. Testing of a PEMFC in a single cell mode by using 3D-FePDC as the cathode catalyst and Nafion membrane delivered a maximum power density of 278 mW cm(-2), which is a promising value expected from a system based on the nonprecious metal cathode. Ultimately, as a cost-effective catalyst that can effectively perform irrespective of the pH conditions, 3D-FePDC offers significant prospects in the areas like fuel cells and metal-air batteries which work in acidic and/or basic conditions.</p>
10aacidic medium10aelectrocatalyst10afuel cell10agraphitic carbon10aIron carbide10anitrogen doping10anonprecious metal10aoxygen reduction reaction1 aGangadharan, Pranav, K.1 aPandikassala, Ajmal1 aKurungot, Sreekumar  uhttps://library.ncl.res.in/content/toward-ph-independent-oxygen-reduction-reaction-polydopamine-derived-3d-interconnected-iron