MoS₂/TiO₂ p-n-Type Heterojunction as a Photoelectrochemical Biosensor for Detecting Dopamine

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Dopamine is vital for neurological regulation, with its levels linked to neurological disorders.
• Precise detection of dopamine is crucial for understanding and diagnosing these conditions.

Purpose of the Study:

• To develop a novel photoelectrochemical (PEC) sensor for sensitive and selective dopamine detection.
• To investigate the properties of a MoS2/TiO2 nanotubes (MoS2/TiO2 NTs) p-n heterojunction nanocomposite for enhanced sensing capabilities.

Main Methods:

• Fabrication of MoS2/TiO2 NTs p-n heterojunction nanocomposite via hydrothermal method.
• Characterization using XRD, SEM, TEM, XPS, EIS, PL, UV-vis, and M-S techniques.
• Performance evaluation of the PEC sensor for dopamine detection under visible light.

Main Results:

• The p-n heterojunction significantly improved charge separation efficiency.
• The optimized sensor achieved a low detection limit of 0.074 μM for dopamine (S/N = 3) within the 1-100 μM range.
• Demonstrated excellent operational stability, selectivity, and rapid response.

Conclusions:

• The MoS2/TiO2 NTs p-n heterojunction platform shows great promise for sensitive dopamine detection.
• Heterojunction engineering is a viable strategy for developing advanced sensors for neuroimaging biomarkers.
• The study provides insights into the PEC enhancement mechanism for biomarker detection.