Two-Dimensional Nickel Porphyrinic Metal-Organic Framework-Modified Electrode for Electrochemical Sensing

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Two-dimensional (2D) metal-organic framework (MOF) nanosheets offer potential for electrochemical sensing due to their active sites and high aspect ratio.
• Developing robust platforms with enhanced detection performance is crucial for advanced sensing applications.

Purpose of the Study:

• To synthesize and characterize a novel nickel-based porphyrinic MOF nanosheet (2D Cu-TCPP(Ni)) for electrochemical sensing.
• To develop a highly selective, sensitive, and stable sensor for detecting p-nitrophenol (p-NP).

Main Methods:

• A solvothermal process using a nickel porphyrin ligand, Cu(NO3)2·3H2O, and polyvinylpyrrolidone (PVP) surfactant to create 2D Cu-TCPP(Ni) MOF nanosheets.
• Modification of a laser-induced graphene electrode with the synthesized 2D Cu-TCPP(Ni) MOF nanosheet.
• Electrochemical detection of p-nitrophenol (p-NP) using differential pulse voltammetry (DPV) and cyclic voltammetry (CV).

Main Results:

• The 2D Cu-TCPP(Ni) MOF nanosheet exhibited excellent selectivity, sensitivity, and stability.
• The sensor demonstrated a detection range of 0.5–200 μM (DPV) and 0.9–300 μM (CV) for p-NP.
• Limits of detection (LOD) were as low as 0.1 μM (DPV) and 0.3 μM (CV).

Conclusions:

• The enhanced electrochemical performance is attributed to the MOF nanosheet's large active surface area, catalytic activity, and adsorption capacity.
• The developed sensor successfully detected p-NP in real sample analysis, indicating its potential for environmental point-of-care testing.