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Catalytically Perfect Enzymes

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The theory of catalytically perfect enzymes was first proposed by W.J. Albery and J. R. Knowles in 1976. These enzymes catalyze biochemical reactions at high-speed. Their catalytic efficiency values range from 108-109 M-1s-1. These enzymes are also called 'diffusion-controlled' as the only rate-limiting step in the catalysis is that of the substrate diffusion into the active site. Examples include triose phosphate isomerase, fumarase, and superoxide dismutase.

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Related Experiment Video

Updated: Sep 11, 2025

Synthesis and Performance Characterizations of Transition Metal Single Atom Catalyst for Electrochemical CO2 Reduction

Synthesis and Performance Characterizations of Transition Metal Single Atom Catalyst for Electrochemical CO2 Reduction

Published on: April 10, 2018

Defect-Engineered Continuous 3D Single-Atom Catalysts for Enhanced Oxygen Reduction Performance.

Zhihao Chen¹, Shu Wang¹, Feng Du¹

¹Institute of Advanced Materials and School of Chemistry and Chemical Engineering, Southeast University, Nanjing, 211189, China.

|August 16, 2025

Summary

This summary is machine-generated.

Defect engineering in iron-nitrogen-carbon structures (Fe─N₄O) enhances single-atom catalysts for the oxygen reduction reaction (ORR). This approach boosts catalytic activity and stability for energy applications.

Keywords:

3D carbon foam defect engineering electrochemistry oxygen reduction reaction single atom catalyst

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Synthesis of Metal Nanoparticles Supported on Carbon Nanotube with Doped Co and N Atoms and its Catalytic Applications in Hydrogen Production

Synthesis of Metal Nanoparticles Supported on Carbon Nanotube with Doped Co and N Atoms and its Catalytic Applications in Hydrogen Production

Published on: December 6, 2021

Area of Science:

Materials Science
Electrochemistry
Catalysis

Background:

Metal atom mobility on carbon substrates causes aggregation, hindering single-atom catalyst performance.
Nitrogen coordination (Nx) anchors single metal atoms, preventing aggregation and forming active sites like Fe─N₄-C.
Strong oxygen intermediate adsorption on Fe sites limits the intrinsic activity of Fe─N₄-C catalysts.

Purpose of the Study:

To develop a novel strategy for stabilizing nitrogen-coordinated iron single atoms (Fe─N₄) to enhance oxygen reduction reaction (ORR) catalytic activity.
To engineer defects in Fe─N₄ structures to create Fe SAs/NPGN catalysts with improved performance.
To investigate the role of defect-synergistic structures in tuning the electronic properties of Fe sites for efficient ORR.

Main Methods:

Synthesis of defect-engineered Fe─N₄O configuration (Fe SAs/NPGN) via ammonia-thermal etching.
Characterization of the catalyst's structure, surface area (2054.39 m² g^-1), and active sites.
Validation of catalytic performance and electronic property tuning through experimental results and theoretical calculations.

Main Results:

The synthesized Fe SAs/NPGN catalyst exhibits significantly boosted ORR catalytic performance.
The defect-engineered structure provides abundant active sites and a high specific surface area.
Tuned electronic properties of Fe sites facilitate more efficient ORR activity, confirmed by experiments and theory.

Conclusions:

Defect engineering of Fe─N₄ sites creates highly active and stable single-atom catalysts for ORR.
The Fe SAs/NPGN catalyst demonstrates a promising pathway for advancing defect-engineered catalysts in energy applications.
This strategy effectively overcomes the limitations of strong oxygen intermediate adsorption in traditional Fe─N₄-C catalysts.