Performance-Enhanced Non-Enzymatic Glucose Sensor Based on Graphene-Heterostructure.

Area of Science:

• Materials Science
• Nanotechnology
• Electrochemistry

Background:

• Non-enzymatic glucose sensing is critical due to market demand for accurate monitoring.
• Existing sensors face challenges in selectivity and sensitivity.
• Graphene-based heterostructures offer promising avenues for enhanced sensor performance.

Purpose of the Study:

• To develop a novel non-enzymatic glucose sensor utilizing a graphene (G)/platinum oxide (PtO)/n-silicon (Si) heterostructure.
• To investigate the effect of PtO film thickness on sensor sensitivity and selectivity.
• To understand the underlying detection mechanisms using theoretical calculations.

Main Methods:

• Fabrication of G/PtO/n-Si heterostructure Schottky diodes.
• Electrochemical testing with varying glucose concentrations and interfering solutions.
• Systematic variation of PtO film thickness.
• Density Functional Theory (DFT) calculations for theoretical investigation.

Main Results:

• The G/PtO/n-Si sensor demonstrated enhanced sensitivity and selectivity for glucose detection.
• Optimizing PtO thickness significantly impacted glucose oxidation efficiency and sensor sensitivity.
• Increasing PtO layer thickness from 30 nm to 50 nm enhanced sensitivity by 150% (up to 30 A/mM.cm²).
• DFT calculations provided insights into charge distribution and selectivity mechanisms.

Conclusions:

• The proposed G/PtO/n-Si heterostructure is a promising platform for developing highly sensitive and selective non-enzymatic glucose sensors.
• PtO layer thickness is a critical parameter for optimizing sensor performance.
• The findings pave the way for more reliable non-enzymatic glucometers for continuous glucose monitoring.