Stress induced to shrink ZIF-8 derived hollow Fe-NC supports synergizes with Pt nanoparticles to promote oxygen reduction electrocatalysis

Abstract

The high cost and insufficient performance of Pt catalysts for the oxygen reduction reaction (ORR) are considered obstacles to the realization of the widespread application of proton exchange membrane fuel cell technology. Here, we report a strategy of integrating a stress-induced shrinkage mechanism and an impregnation reduction method to disperse Pt nanoparticles (NPs) onto stress-induced to shrink ZIF-8 derived hollow N-coordinated Fe atom embedded in carbon (Fe-NC) dodecahedron nanomaterials to obtain a fantastic-performance Pt@Fe-NC electrocatalyst for the oxygen reduction reaction (ORR). The prepared Pt@Fe-NC shows high ORR activity due to its multiple active centers and hollow porous structure conducive to mass transfer. The half-wave potential for Pt@Fe-NC is 0.936 V, and the mass activity of 1.34 A mg_pt⁻¹ is 6.77 times that of commercial Pt/C (0.198 A mg_pt⁻¹). Stability examinations demonstrate that Pt@Fe-NC shows higher catalytic durability than Pt/C catalysts. DFT calculations revealed that the interaction between Pt NPs and Fe-NC supports would enhance the anchoring of Pt and would weaken the adsorption of *OH intermediates on Pt and Fe sites, enhancing ORR intrinsic activity. Our work provides a new direction for exploring noble metal Pt and metal–nitrogen–carbon synergy to realize electrocatalysts designed for a highly active ORR.