High surface area nitrogen-functionalized Ni nanozymes for efficient peroxidase-like catalytic activity

Area of Science:

• Materials Science
• Nanotechnology
• Catalysis

Background:

• Nanozymes offer promising catalytic properties, but their performance can be limited.
• Surface functionalization is a key strategy to enhance nanozyme activity.
• Nitrogen-functionalization has shown potential for improving nanozyme catalytic efficiency.

Purpose of the Study:

• To investigate the effect of plasma-assisted nitrogen modification on the peroxidase-like activity of nanocolumnar Ni GLAD films.
• To optimize the plasma treatment conditions for enhanced nanozyme performance.
• To explore the application of nitrogen-functionalized Ni nanozymes in continuous catalytic systems.

Main Methods:

• Plasma-assisted nitrogen modification using ammonia plasma on Ni GLAD films.
• Characterization using Transmission Electron Microscopy (TEM), Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD), and X-ray Photoelectron Spectroscopy (XPS).
• Assay of peroxidase-like activity using TMB (3,3',5,5'-Tetramethylbenzidine) and H2O2 (hydrogen peroxide), determining kinetic parameters (Vmax and Km).

Main Results:

• Nitrogen-functionalization resulted in a nitrogen-rich surface composition and increased surface wettability.
• Plasma-treated Ni nanozymes exhibited significantly enhanced peroxidase-like catalytic activity compared to pristine Ni films.
• Optimal plasma treatment time was found to be 120 seconds, yielding a higher maximum reaction velocity and lower Michaelis-Menten coefficient.
• Demonstrated application in a gravity-driven, continuous catalytic reaction device.

Conclusions:

• Plasma-assisted nitrogen modification is an effective strategy to improve the catalytic performance of Ni nanozymes.
• The enhanced activity is attributed to the nitrogen-rich surface and increased wettability.
• This approach offers a controllable method for developing surface-functionalized nanozymes with potential for point-of-care devices.