2D Single-Atom Fe–N–C Catalyst Derived from a Layered Complex as an Oxygen Reduction Catalyst for PEMFCs

Abstract

Fe single-atom catalysts of oxygen reduction reaction (ORR) are restricted by the agglomeration during the synthesis process and inferior stability, especially in acidic conditions. An efficient synthesis strategy is urgently needed to alleviate these disadvantages. In this work, a two-dimensional (2D) single-atom Fe−N−C catalyst derived from a layered complex was designed and synthesized for the ORR. Fe single atoms dispersed on 2D hierarchical porous N-doped carbon nanosheets (Fe−N− C) were derived from a layered complex through the coordination of Fe 3+ and benzidine hydrochloride. The unique 2D hierarchical porous nanosheets with a special edge effect can not only provide a large specific surface area and promote the mass transfer of ORR but also facilitate the affinity of Fe single atoms. Furthermore, the well-distributed Fe single atoms and Fe−N x −C structure can increase the utilization rate of metal atoms and enhance the catalytic activity of materials. As expected, the catalyst shows superior ORR performance and excellent electrochemical stability.

Preparation of single atom catalysts for high sensitive gas sensing

“…Fe(SA)/N-C 2.16 [167] SA [167] Pt(SA)/Ce-MOF 0.12 [168] SA [168] Fe(SA)/N-C 0.94 [172] SA [172] Rh(SA)/ZSM-5-H 0.45 ∼ 0.71 [135] SA [135] densities and high productivity remains a significant hurdle in the pathway to the industrialization of SACs. Recently, Hai et al proposed a general method to realize atomic-level dispersion of 15 types of metal atoms with loadings up to 23 wt% on different supports.…”

“…Analogously, Yin et al obtained the well-dispersed single-atom Fe catalysts (Fe(SA)/N-C) dispersed on 2D hierarchical porous N-doped carbon nanosheets. This was achieved through the coordination and steric hindrance between Fe 3+ and benzidine hydrochloride, preventing aggregation during the pyrolysis process [172].…”

Atomically Dispersed Metal‐Nitrogen‐Carbon Electrocatalysts for the Oxygen Reduction Reaction

“…Meanwhile, the ORR activity of M-N-C electrocatalysts can be optimized by modifying the center metal and coordination environment. To date, a broad range of center metals (e. g., Fe, [15][16][17][18][19][20][21] Co, [22][23][24][25][26][27][28] Ni, [29][30][31][32][33][34] Cu, [35][36][37][38][39][40][41] Cr, [42][43][44][45] Mn, [46][47][48][49][50][51][52][53][54][55] etc.) have been developed, with particular emphasis on the Fe-N-C structure, which has drawn considerable attention for exhibiting superior ORR activity compared to Pt in alkaline solution.…”

A Surrogate Machine Learning Model for the Design of Single-Atom Catalyst on Carbon and Porphyrin Supports towards Electrochemistry

“…Single-atom catalysts (SACs) are extensively applied for various electrochemical reactions to produce value-added chemicals − due to their high atom utilization efficiency along with their unique properties. − According to their widespread applications, the rational design of SACs has received a lot of interest in improving the feasibility and efficiency of optimizing the desired products. , Density functional theory (DFT) calculations are mostly applied for the rational design of SACs with a focus on high activities and selectivities . However, DFT calculations are computationally expensive and time-consuming , due to the fact that the complexity of structure–activity relationships requires a huge number of nontrivial DFT calculations in a vast dimensional space, such as environmental coordination, SAC type, and reactants .…”