Specific detection against diazinon by using Schottky junction driven photoelectrochemical aptasensor

Area of Science:

• Materials Science
• Analytical Chemistry
• Environmental Science

Background:

• Diazinon (DIA) hydrolysis yields toxic compounds, posing risks to aquatic life and public health.
• Existing detection methods for DIA may lack sensitivity or specificity.
• There is a need for advanced sensors for effective pesticide residue monitoring.

Purpose of the Study:

• To develop a sensitive photoelectrochemical (PEC) aptasensor for diazinon detection.
• To utilize Mo2N nanoparticles integrated with g-C3N4 to create efficient electron acceptor materials.
• To investigate the role of Schottky junctions in enhancing PEC sensing performance.

Main Methods:

• Fabrication of a Mo2N/g-C3N4 composite material for enhanced photoactivity.
• Construction of a PEC aptasensor by immobilizing DIA-specific aptamers on the electrode.
• Utilizing the internal electric field (IEF) generated Schottky junctions to promote charge transfer and reduce recombination.
• Characterization of the sensor's performance using electrochemical and spectroscopic techniques.

Main Results:

• The Mo2N/g-C3N4 composite exhibited enhanced photocurrent generation under visible light due to improved charge collection and reduced electron-hole recombination.
• The developed PEC aptasensor demonstrated a broad linear range (5 × 10⁻³–1 × 10³ pM) and an ultra-low detection limit (1.67 × 10⁻³ pM) for DIA.
• The sensor showed high accuracy, selectivity, and applicability in real water samples, indicating its practical utility.

Conclusions:

• The Mo2N/g-C3N4 based PEC aptasensor provides a highly sensitive and selective platform for diazinon detection.
• The integration of Schottky junctions effectively amplifies sensing signals and improves sensor performance.
• This work offers valuable insights for developing advanced PEC aptasensors for pesticide residue monitoring.