Low-Power and Eco-Friendly Temperature Sensor Based on Gelatin Nanocomposite

Area of Science:

• Materials Science
• Electrochemistry
• Sensor Technology

Background:

• Development of sustainable and cost-effective sensing materials is crucial for environmental monitoring.
• Electrochemical sensors offer sensitive detection capabilities for various physical parameters.

Purpose of the Study:

• To fabricate and characterize an environmentally-friendly temperature sensor using a water-processable gelatin-graphene nanocomposite.
• To investigate the electrochemical properties and temperature-dependent behavior of the sensor.
• To assess the sensor's capability for detecting frost formation at subzero temperatures.

Main Methods:

• Fabrication of a nanocomposite material using gelatin and graphene.
• Electrochemical characterization using cyclic voltammetry, chronopotentiometry, and impedance spectroscopy.
• Device fabrication with a sandwich structure between metal foils and the graphene-gelatin blend.
• Design of a driving circuit to enhance sensor stability and reduce signal drift.

Main Results:

• The sensor demonstrated temperature-dependent open-circuit voltage in the 260-310 K range.
• The device successfully detected ice/frost formation at subzero temperatures.
• A detailed model was proposed for charge carrier accumulation, transfer, and diffusion processes.
• The sensor exhibited a temperature sensitivity of approximately -19 mV/K.
• The sensor showed long-term stability, fast response, and low-power consumption (microwatts).

Conclusions:

• A novel, eco-friendly, and low-cost temperature sensor based on gelatin-graphene nanocomposite has been successfully developed.
• The sensor is suitable for environmental monitoring, particularly for indoor applications, due to its performance and low power requirements.
• The ability to detect frost formation adds significant value for specific environmental monitoring scenarios.