High density iridium synergistic sites boosting CO-tolerate performance for PEMFC anode

The usage of cheap crude H 2 in proton-exchange membrane fuel cells (PEMFCs) is still unrealistic to date, due to the suffering of the current Pt based nano-catalysts from impurities such as CO in anode. Recently, synergistic active sites between single atom (SA) and nanoparticle (NP) have been found to be promising for overcoming the poisoning problem. However, lengthening the nanoparticle-single atom (SA–NP) interface, i.e., constructing high density synergistic active sites, remains highly challenging. Herein, we present a new strategy based on molecular fusion strategy to create abundant SA–NP interfaces, with high density SA–NP interfaces created on a two dimensional nitrogen doped carbon nanosheets (Ir-SACs&NPs/NC). Owing to the abundance of SA–NP interface sites, the catalyst was empowered with a high tolerance towards up to 1000 ​ppm CO in H 2 feed. These findings provide guidelines for the design and construction of active and anti-poisoning catalysts for PEMFC anode. • Through molecular fusion strategy, overcome the active site loading limitation during construction of synergetic sites. • With significantly lengthened Ir NPs–SAs interface, CO species can be oxidized facilely. • We propose that the single atom sites act as efficient CO scavenger for synergetic metal particles.