Multilayer stabilization for fabricating high-loading single-atom catalysts

Abstract

Metal single-atom catalysts (M-SACs) have emerged as an attractive concept for promoting heterogeneous reactions, but the synthesis of high-loading M-SACs remains a challenge. Here, we report a multilayer stabilization strategy for constructing M-SACs in nitrogen-, sulfur- and fluorine-co-doped graphitized carbons (M = Fe, Co, Ru, Ir and Pt). Metal precursors are embedded into perfluorotetradecanoic acid multilayers and are further coated with polypyrrole prior to pyrolysis. Aggregation of the metals is thus efficiently inhibited to achieve M-SACs with a high metal loading (~16 wt%). Fe-SAC serves as an efficient oxygen reduction catalyst with half-wave potentials of 0.91 and 0.82 V (versus reversible hydrogen electrode) in alkaline and acid solutions, respectively. Moreover, as an air electrode in zinc–air batteries, Fe-SAC demonstrates a large peak power density of 247.7 mW cm−2 and superior long-term stability. Our versatile method paves an effective way to develop high-loading M-SACs for various applications.

A Versatile Approach to Boost Oxygen Reduction of Fe‐N4 Sites by Controllably Incorporating Sulfur Functionality

“…Thus, these catalysts should encompass the efficient active sites to optimize oxygen species adsorption for low overpotential, desirable pore organization to enhance active sites exposure and mass transport, as well as a predictable structure to unveil the ORR mechanism. [5][6][7] Due to maximized atom efficiency, single atom catalysts (SACs) have been regarded as promising substitute for Ptbased catalysts in heterogeneous ORR catalysis. [8] Over the last few years, the graduated escalation in catalytic activity of SACs has been attained, with single-atom Fe-N 4 site presenting the best one among vast metal-nitrogen (M-N x ) sites.…”

Atomically Structural Regulations of Carbon‐Based Single‐Atom Catalysts for Electrochemical CO2Reduction

“…Reproduced with permission. [133] Copyright 2020, Nature Publishing Group. configurations and local microenvironments, these heterogenized molecular SACs can serve as excellent model systems to reveal the structure-activity relationship in CO 2 RR.…”

“…d) Illustration of the preparation of Fe-SA-NSFC. Reproduced with permission [133]. Copyright 2020, Nature Publishing Group.…”

Inhibiting Surface Diffusion to Synthesize 3D Bicontinuous Nanoporous N‐Doped Carbon for Boosting Oxygen Reduction Reaction in Flexible All‐Solid‐State Al‐Air Batteries

“…Linking the FTIR results (Figure S7, Supporting Information) with the SEM observations The chemical state and elemental composition were quantitatively investigated by X-ray photoelectron spectroscopy (XPS). The high-resolution C 1s spectrum of N-NPC samples presented the peaks at 284.6, 285.7, 286.9, and 289.2 eV, which can be assigned to CC, CN, CO, and CO bonds, [29,30] respectively (Figure S9, Supporting Information). The high-resolution N 1s spectrum revealed that the N dopants can be divided into pyridinic N (398.7 eV), graphitic N (400.9 eV), and oxidized N (403.0 eV) (Figure 2c).…”