Aerogel Technologies for Thermal Insulation Applications

Aerogels represent a class of ultra-light, highly porous materials in which a nano-structured solid network encloses an air-filled pore system. Their exceptionally low density and high porosity confer record-low thermal conductivities, making them among the most effective solid thermal insulators. Traditional silica aerogels are synthesised via a sol–gel process followed by supercritical drying to preserve the delicate pore architecture. Advances have extended this paradigm to biopolymer-derived cellulose aerogels, ceramic and metal-oxide nanofibrous frameworks, and organic–inorganic hybrid composites. By tuning pore size distribution, fibre alignment and surface chemistry, researchers have realised aerogels that combine optical transparency, mechanical resilience and stability under extreme temperatures. Applications span building envelopes—where aerogel panels and glazing inserts boost energy efficiency—to aerospace and electronics, where lightweight thermal shields protect sensitive components, and to battery systems, where thermally insulating barriers mitigate runaway events. These developments highlight the global potential of aerogel technologies for sustainable thermal management in energy-saving and safety-critical contexts.

Research from Nature Portfolio

Recent studies have demonstrated that cellulose-based aerogels can combine exceptional optical clarity with ultra-low thermal conductivity, achieving visible-range light transmission of up to 99% and thermal conductivities below that of still air. These materials, fabricated by colloidal self-assembly and roll-to-roll processing, offer retrofit solutions for insulating glass units that dramatically reduce heat loss while maximising daylight transmission. Another line of research has introduced hypocrystalline zircon nanofibrous aerogels designed for extreme environments. By engineering a zig-zag nanofibre architecture and deliberately entrapping residual carbon, these aerogels maintain structural integrity and exhibit one of the lowest high-temperature thermal conductivities reported, all while displaying near-zero thermal expansion and Poisson’s ratio at temperatures exceeding 1,000 °C.

Aerogel Technologies for Thermal Insulation Applications publication trend

The graph below shows the total number of articles in aerogel technologies for thermal insulation applications across all publications each year (not limited to Nature Index journals).

Technical terms

Aerogel: A highly porous solid material in which the liquid phase of a gel has been replaced by gas, yielding extremely low density and high surface area.

Thermal conductivity: A measure of a material’s ability to conduct heat, expressed in watts per metre per kelvin (W m⁻¹ K⁻¹).

Sol–gel process: A chemical synthesis route in which a colloidal solution (sol) undergoes gelation to form a three-dimensional solid network (gel).

Supercritical drying: A method for removing liquid from gels by transitioning through a supercritical fluid phase, preventing capillary forces from collapsing the pore structure.

Poisson’s ratio: The negative ratio of transverse to axial strain when a material is stretched, indicating its lateral deformation behaviour under load.

Nanofibre: A fibre with diameters on the order of nanometres, which can form interconnected networks with high porosity and enhanced mechanical properties.

References

1. Highly transparent silanized cellulose aerogels for boosting energy efficiency of glazing in buildings. Nature Energy (2023).
2. Multifunctional Integrated Organic–Inorganic-Metal Hybrid Aerogel for Excellent Thermal Insulation and Electromagnetic Shielding Performance. Nano-Micro Letters (2024).
3. Thermally insulating and fire‐retardant bio‐mimic structural composites with a negative Poisson's ratio for battery protection. Carbon Energy (2023).
4. Silica Aerogel: Synthesis and Applications. Journal of Nanomaterials (2010).
5. Hypocrystalline ceramic aerogels for thermal insulation at extreme conditions. Nature (2022).