Highly Robust 3D rGO Aerogel with Tunable Thermoelectric Effect for Multifunctional Sensing Applications

Area of Science:

• Materials Science
• Nanotechnology
• Energy Harvesting

Background:

• Growing demand for all-carbon-based flexible sensors necessitates multifunctional materials.
• Existing 3D graphene structures often lack optimized properties for diverse stimuli response.

Purpose of the Study:

• To create a novel three-dimensional (3D) reduced graphene oxide thermoelectric aerogel (rGOTEA).
• To achieve multifunctional sensing capabilities and energy harvesting in a flexible, all-carbon-based material.

Main Methods:

• Bottom-up assembly using reduced graphene oxide (rGO) sheets.
• Bidirectional freeze-squeezing and reconstructing treatments for 3D aerogel formation.
• Quantitative regulation of oxygen-containing groups and interfacial bonding.

Main Results:

• Fabricated 3D rGOTEA with lightweight density (≤5.4 mg cm⁻³), superelasticity (≥90% recoverable strain), and fatigue resistance.
• Achieved decoupled carrier transport and phonon scattering for optimized thermoelectric performance.
• Exhibited high electrical conductivity (95.834 S m⁻¹) and low thermal conductivity (0.028 W m⁻¹ K⁻¹).
• Demonstrated tunable Seebeck coefficient (6.9–19.5 μV/K) enabling sensitive detection of physical signal fluctuations.
• rGOTEA device showed multifunctional sensing to thermal, electrical, and mechanical stimuli.
• Assembled rGOTEA thermal energy converter produced 600 μV under a 2.4 K/mm temperature gradient.

Conclusions:

• The 3D rGOTEA offers a versatile platform for multifunctional sensors, thermal insulation, and energy harvesting.
• The material's unique structure and tunable properties address the need for advanced flexible electronic devices.
• This work highlights promising applications in wearable electronics and sustainable energy solutions.