Development of an acetone sensor using nanostructured Co₃O₄ thin films for exhaled breath analysis

Area of Science:

• Materials Science
• Chemical Sensing
• Biomedical Diagnostics

Background:

• Diabetic Keto-Acidosis (DKA) detection is critical in healthcare.
• Acetone in exhaled breath is a key biomarker for DKA.
• Advanced diagnostics require sensitive and specific breath sensors.

Purpose of the Study:

• To fabricate nanostructured cobalt oxide thin films for acetone sensing.
• To investigate the effect of deposition temperature on film properties.
• To develop a highly sensitive acetone sensor for DKA detection.

Main Methods:

• Spray pyrolysis technique used for cobalt oxide thin film deposition at varying temperatures (473–773 K).
• Structural analysis (XRD) and optical property analysis (UV-Vis, PL) to characterize films.
• Fabrication and testing of acetone sensor performance at room temperature.

Main Results:

• Cubic spinel phase cobalt oxide formation confirmed.
• Higher deposition temperatures (773 K) led to favorable atomic migration and optical property changes.
• The sensor fabricated at 773 K exhibited a high sensing response (235) to 50 ppm acetone.
• Achieved a low limit of detection (LOD) of 1 ppm with rapid response (6 s) and recovery (4 s).

Conclusions:

• Nanostructured cobalt oxide thin films are promising for acetone sensing.
• Optimized deposition temperature significantly enhances sensor performance.
• The developed sensor's low LOD is below the DKA threshold, enabling early detection.