Insight into role of Ni/Fe existing forms in reversible oxygen catalysis based on Ni-Fe single-atom/nanoparticles and N-doped carbon

Tailoring supports for enhancing the electrocatalytic hydrogen evolution performance of platinum species: a review

“…(I) Vacancy engineering advantages: introducing vacancies can increase the active sites and facilitate charge transfer, leading to improved catalytic activity; disadvantages: vacancy engineering may alter the structural stability of the catalyst, potentially reducing its durability and long-term performance. 169 (II) Morphology control advantages: by controlling the morphology, catalysts can have increased surface area, improved mass transport, and enhanced utilization of active sites, resulting in higher electrocatalytic activity; disadvantages: complex synthesis methods may be required to achieve specific morphologies, and maintaining the desired morphology under harsh operating conditions can be challenging. 170 (III) Heterostructure tuning advantages: combining different materials in a heterostructure can create synergistic effects, such as improved charge transfer and enhanced stability, leading to enhanced electrocatalytic activity; disadvantages: precise control over the heterostructure composition and interface can be difficult, and the synthesis of heterostructures may involve complex fabrication techniques.…”

Machine-learning-accelerated screening of single metal atoms anchored on MnPS3 monolayers as promising bifunctional oxygen electrocatalysts

“…Developing sustainable and green energy technologies is extremely urgent in order to solve the growing energy crisis and environmental pollution and ensure a safe and sustainable future. 1,2 In this respect, fuel cells, 3,4 metal-air batteries 5,6 and water-splitting systems 7,8 have been widely regarded as promising alternatives to traditional fossil fuels owing to their high energy density and environmental friendliness. Notably, in these sustainable energy conversion and storage devices, the oxygen reduction reaction (ORR) and the oxygen evolution reaction (OER) are two key anode/ cathode reaction processes that affect or determine the electrochemical reaction rates of these devices.…”

Nanoporous-Structured Fe-NC Single-Atom Electrocatalysts Based on Lotus Seedpods and Industrial Acid Residues for Efficient Oxygen Reduction Reaction

“…The high-resolution Fe 2p spectrum in Figure 3c presents the doublets of Fe 2+ 2p (710.2, 723.7 eV) and Fe 3+ 2p (713.7, 728.9 eV), in which the resonance at ∼529 eV assigned to the O−Fe bonding was absent, underlining ineffective coordination between O and Fe (Figure S3b). 34 The N 1s spectrum (Figure 3d) of FeNC-SAC-LS displays four deconvoluted peaks, corresponding to four chemical forms of N, i.e., oxidized N (402.8 eV), graphitic N (401.1 eV), pyrrolic N (400.1 eV), and pyridinic N (398.2 eV), and pyridinic N and graphitic N are the dominant components (Table S3); pyridinic N can easily coordinate with Fe species to form FeN x configurations that are vital for accelerating the ORR process, while the graphitic N can amplify the electron transfer, particularly in the region of limited current density. 34 XAS measurements, which include the X-ray absorption near edge structure (XANES) and extended X-ray absorption fine structure (EXAFS), were performed to reveal accurate elemental coordination information on FeNC-SAC-LS.…”

“…34 The N 1s spectrum (Figure 3d) of FeNC-SAC-LS displays four deconvoluted peaks, corresponding to four chemical forms of N, i.e., oxidized N (402.8 eV), graphitic N (401.1 eV), pyrrolic N (400.1 eV), and pyridinic N (398.2 eV), and pyridinic N and graphitic N are the dominant components (Table S3); pyridinic N can easily coordinate with Fe species to form FeN x configurations that are vital for accelerating the ORR process, while the graphitic N can amplify the electron transfer, particularly in the region of limited current density. 34 XAS measurements, which include the X-ray absorption near edge structure (XANES) and extended X-ray absorption fine structure (EXAFS), were performed to reveal accurate elemental coordination information on FeNC-SAC-LS. Figure 3e illustrates the Fe K-edge XANES spectra of FeNC-SAC-LS, Fe foil, Fe 2 O 3 , and FeO, where the pre-edge peak and nearedge adsorption energy of FeNC-SAC-LS are between those of Pore volume (cm 3 g −1 )…”