Iron phosphide nanocrystals decorated in situ on heteroatom-doped mesoporous carbon nanosheets used for an efficient oxygen reduction reaction in both alkaline and acidic media

Abstract

Oxygen reduction catalysts based on heteroatom-doped mesoporous carbon nanosheets loaded with highly crystalline FeP nanoparticles (FeP@FePNCs) were fabricated using a simple, one-step carbonization-phosphization methodology. The obtained FeP@FePNCs exhibited outstanding catalytic activity and durability towards the oxygen reduction reaction (ORR) in alkaline media. Moreover, the FeP@FePNCs also displayed high-performance in acidic media. The remarkable ORR activity originates from the synergetic effects between the embedded FeP nanoparticles and the heteroatom-doped carbon structures. Moreover, the porous structure, high specific surface area, and electron conductivity can contribute to enhance the ORR performance.

Mechanisms of Two‐Electron versus Four‐Electron Reduction of Dioxygen Catalyzed by Earth‐Abundant Metal Complexes

“…Although molecular catalysis by iron porphyrins has provided valuable mechanistic insights into the two‐electron/two‐proton vs. four‐electron/four‐proton reduction of O 2 , a large number of heterogeneous iron‐based materials were reported to act as much better catalysts for electrochemical reduction of O 2 than homogeneous iron complex catalysts . Even better ORR electrocatalytic performance has been reported for a two dimensional (2D) poly‐iron‐phthalocyanine PFe‐Pc, than for the state‐of‐the‐art 20 % platinum/carbon (Pt/C) catalyst in alkaline medium.…”

Encapsulated FeP nanoparticles with in-situ formed P-doped graphene layers: Boosting activity in oxygen reduction reaction

“…Although many efficient electrocatalysts of carbon/iron phosphide (FeP) NPs were reported for oxygen evolution reaction (OER) and hydrogen evolution reaction (HER), only a few FeP-based ORR catalysts have been studied so far [23][24][25][26]. For example, Zhang et al [24] prepared carbon nanosheets with embedded FeP NPs for OER and ORR.…”

Electrochemical impacts of sheet-like hafnium phosphide and hafnium disulfide catalysts bonded with reduced graphene oxide sheets for bifunctional oxygen reactions in alkaline electrolytes

“…For ORR, the onset potential of HfP-rGO NS (0.97 V vs. RHE) is lower than that of Pt/C (1.05 V vs. RHE), but higher than that of HfS 2 -rGO NS (0.95 V vs. RHE), N/Fe-co-doped G (0.87 V), 46 FeP@NPC (0.9 V), 31 FeNiS 2 NS (0.79 V), 36 Ni 9 S 8 NR (0.68 V), 36 FeS NS (0.32 V), 36 FeP@PNC-800 (0.76 V), 32 Fe x P/NPCS (0.9 V), 25 rGO-Co-Pi (0.91 V), 33 Co 4 N/rGO (0.87 V) 8 and N-CG-CoO (0.9 V) 1 catalysts. Similarly, the ORR peak current density (J peak ) of HfP-rGO NS (1.16 mA cm À2 ) is superior to Pt/C (0.85 mA cm À2 ), HfS 2 -rGO NS (0.61 mA cm À2 ), FeP@PNC-800 (0.8 mA cm À2 ), 32 rGO-Co-Pi (0.35 mA cm À2 ) 33 and V(C,N) (0.13 mA cm À2 ) 34 catalysts. Furthermore, the peak potential of ORR of HfP-rGO NS (0.79 V vs. RHE) is higher than that of FeP@PNC-800 (0.58 V), 32 Co 9 S 8 /G (0.69 V) 35 and N-Co 9 S 8 /G (0.7 V).…”

“…8,28 The combination of rGO sheets with metallic compounds (i.e., heteroatom doping) can improve the electronic conductivity and increase the surface area, and hence make the electrocatalyst highly active due to the synergistic effects. 14,29,30 Similarly, many active heterogeneous catalysts, such as FeP@NPC, 31 FeP@PNC-800, 32 Fe x P/NPCS, 25 34 N-Co 9 S 8 /G 35 and FeS NS, 36 have been reported for the ORR/OER. However, the need remains to achieve highperformance bifunctional electrocatalysts in bulk applications for energy conversion devices based on oxygen electrocatalysis.…”