One-Step Synthesis of Copper Single-Atom Nanozymes for Electrochemical Sensing Applications

Area of Science:

• Materials Science
• Nanotechnology
• Electrochemistry

Background:

• Single-atom nanozymes (SANs) offer combined nanomaterial and atomic metallic site properties.
• Existing SAN synthesis methods suffer from poor loading, aggregation, and low yields.

Purpose of the Study:

• To develop a facile and green synthesis for copper single-atom nanozymes (Cu SANs).
• To create a novel Cu SANs/laser-scribed graphene (LSG) composite material.
• To evaluate the performance of Cu SANs/LSG in electrochemical sensing applications.

Main Methods:

• A single-step, green synthesis using CO2 laser to anchor copper precursor onto a polyimide sheet, simultaneously creating laser-scribed graphene (LSG) support.
• Characterization of atomic copper on LSG using high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) and X-ray photoelectron spectroscopy (XPS).
• Fabrication of a working electrode using the Cu SANs/LSG composite for amperometric detection of hydrogen peroxide (H2O2).

Main Results:

• Successfully synthesized Cu SANs with a surface metal loading of 1.47% ± 0.16% on LSG.
• Verified the presence of atomic Cu on the LSG surface through advanced microscopy and spectroscopy.
• Achieved a low detection limit of 2.40 μM for H2O2 using the Cu SANs/LSG electrode.
• Demonstrated high sensitivity for H2O2 detection, reaching 130.0 μA mM⁻¹ cm⁻².

Conclusions:

• The developed green, single-step method provides an efficient route for Cu SANs synthesis.
• The Cu SANs/LSG composite exhibits excellent performance for electrochemical H2O2 sensing.
• This material holds promise for applications in oxidative stress assessment.