Chemical Vapor Deposition for N/S-Doped Single Fe Site Catalysts for the Oxygen Reduction in Direct Methanol Fuel Cells

Abstract

Single metal site catalysts are the most promising candidates to replace platinum-group-metal (PGM) catalysts for the oxygen reduction reaction (ORR), yet insufficient performance and scalable preparation approaches remain great challenges. Here, we report a nitrogen (N)/sulfur (S) codoped single Fe site catalyst (Fe–N/S–C) through a chemical vapor deposition (CVD) strategy. Using the cyclopentadiene-shielded Fe atom ferrocene (Fc) as the precursor, atomically dispersed single Fe sites were successfully embedded into the N, S codoped 2D carbon nanosheets. The superior catalytic activity for the ORR in alkaline media is stemmed from the N, S codoping, tuning the optimal charge distribution of Fe sites. In addition, the CVD approach could surpress the formation of iron-carbide-containing iron clusters (“Fe x C/Fe”), thereby leading to high surface areas and porosity. Furthermore, the Fe–N/S–C catalyst was further studied as a cathode catalyst in direct methanol fuel cells showing encouraging performance.

A well-defined S-g-C3N4/Cu–NiS heterojunction interface towards enhanced spatial charge separation with excellent photocatalytic ability: synergetic effect, kinetics, antibacterial activity, and mechanism insights

“…25 Non-metallic element decoration (O, halogen elements, S, B, and P) is one of the viable solutions, as it may change the electrical properties and enhance the visible light-harvesting potential while still maintaining charge transference. [26][27][28] For example, Liu fabricated Sengineered g-C 3 N 4 by reacting g-C 3 N 4 with H 2 S as a S source at 449 C, which demonstrated signicantly higher photocatalytic H 2 evaluation ability than undoped g-C 3 N 4 . 29 Hong et al described that mesoporous SCN showed thirty times greater H 2 generation activity than pure g-C 3 N 4 .…”

Emerging Single‐Atom Catalysts/Nanozymes for Catalytic Biomedical Applications

“…SACs can be synthesized through many other methods, such as acid leaching, [43] ball milling, [44] pressurized gasassisted low-temperature treatment, [45] atom trapping, [46] electrochemical activation, [47] hydrothermal synthesis, [48] solvothermal synthesis, [49] chemical vapor deposition, [50] impregnation, [51] site-specific electrodeposition, [52] etc., but these approaches frequently suffer from the shortcomings of low yield and insufficient metal loading, which seriously reduce their practical application value. [53] As shown in Table 1, some frequently used synthetic methods and their advantages and disadvantages are also summarized.…”

Modeling the roles of rigidity and dopants in single-atom methane-to-methanol catalysts

“…8,19 Similarly, different coordinating atom identities provide distinct ligand field strengths which could influence SAC properties and catalysis. 21–29…”