Synergistic effect of boron/nitrogen co-doping into graphene and intercalation of carbon black for Pt-BCN-Gr/CB hybrid catalyst on cell performance of polymer electrolyte membrane fuel cell

Abstract

Boron and nitrogen were successfully co-doped into graphene (Gr) nanosheets to which Pt nanoparticles with ∼3.7 nm are uniformly deposited on BCN-Gr. Pt content on BCN-Gr is estimated to be 50 wt.% by TG/DTA analysis. Pt-BCN-Gr is intercalated by different amount of CB (carbon black), and it is designated as Pt-BCN-Gr/CBx (x = 0.0, 0.3, 0.4, 0.5 and 0.6). The membrane electrode assembly is fabricated with commercial Pt-C and Pt-BCN-Gr/CBx as anode and cathode catalysts, respectively. The cell performance is highly consistent with electrochemical active surface area and the best cell performance of 0.54 W/cm2 in power density is achieved for Pt-BCN-Gr/CB0.5. The results show that positive effect of B and N co-doping on cell performance becomes more significant for lower intercalated CB content. Direct comparison between Pt-BCN-Gr/CB and Pt-Gr/CB clearly exhibits that Pt-BCN-Gr/CB shows better cell performance for Pt-BCN-Gr/CB than Pt-Gr/CB at lower CB content. About 28%–157% in cell performance at 0.6 V has been enhanced by B and N co-doping compared with that of Pt-Gr/CB. The enhancement in cell performance and durability is probably attributed to the synergistic effect by B and N co-doping and intercalation by CB.