To exploit the high-temperature superinsulation potential of anisotropic thermal management materials, the incorporation of ceramic aerogel into the aligned structural networks is indispensable. However, the long-standing obstacle to exploring ultralight superinsulation ceramic aerogels is the inaccessibility of its mechanical elasticity, stability, and anisotropic thermal insulation. In this study, we report a recoverable, flexible ceramic fiber-aerogel composite with anisotropic lamellar structure, where the interfacial cross-linking between ceramic fiber and aerogel is important in its superinsulation performance. The resulting ultralight aerogel composite exhibits a density of 0.05 g/cm3, large strain recovery (over 50%), and low thermal conductivity (0.0224 W m–1 K–1), while its hydrophobicity is achieved by in situ trichlorosilane coating with the water contact angle of 135°. The hygroscopic tests of such aerogel composites demonstrate a reversible thermal insulation. The mechanical elasticity and stability of the anisotropic composites, with its soundproof performance, shed light on the low-cost superelastic aerogel manufacturing with scalability for energy saving building applications.

Silica aerogel gives rise to much attention due to its unique nanoporous network, which consists of nanoscale connective silica particles and high-volume nanoscale pores. This lightweight superinsulation solid material is...

Polymer dielectrics, an insulating material ubiquitous in electrical power systems, must be ultralight, mechanically and dielectrically strong, and very thermally conductive. However, electric and thermal transport parameters are intercorrelated in a way that works against the occurrence of thermally conductive polymer electric insulators. Here, we describe how solution gel-shearing-strained polyethylene yields an electric insulating material with an outstanding in-plane thermal conductivity of 10.74 W m −1 K −1 and an average dielectric constant of 4.1. The dielectric constant and loss of such sheared polymer electric insulators are nearly independent of the frequency and a wide temperature range. The gel-shearing aligns ultrahigh-molecular weight polymer crystalline chains for the formation of separated and aligned nanoscale fibrous arrays. Together with lattice strains and the presence of boron nitride nanosheets, the dielectric polymer shows high current density carrying and high operating temperature, which is attributed to greatly enhanced heat conduction.

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Advanced high-temperature materials, metals and ceramics, have been widely sought after for printed flexible electronics under extreme conditions. However, the thermal stability and electronic performance of these materials generally diminish under extreme environments. Additionally, printable electronics typically utilize nanoscale materials, which further exacerbate the problems with oxidation and corrosion at those extreme conditions. Here we report superior thermal and electronic stability of printed copper-flexible ceramic electronics by means of integral hybridization and passivation strategies. High electric conductivity (5.6 MS/m) and thermal stability above 400 °C are achieved in the printed graphene-passivated copper platelet features, while thermal management and stability above 1000 °C of printed electronics can be achieved by using either ultrathin alumina or flexible alumina aerogel sheets. The findings shown here provide a pathway toward printed, extreme electronic applications for harsh service conditions.

Thermal insulation of solid materials originates from the nanoscale porous architectures to regulate thermal management in energy-critical applications from energy-efficient buildings to heat-sensitive energy devices. Here, we show nanoengineering of porous silica materials to control the architecture transition from mesoporous to nanocage networks. A low thermal conductivity of such a porous silica network is achieved at 0.018 W/(m K) while exhibiting a porosity of 92.05%, specific surface area of 504 m2/g, and pore volume of 2.37 cm3/g after ambient pressure drying. Meanwhile, the crosslinking of the porous silica and ceramic fiber frameworks show a tensile Young’s modulus of 2.8 MPa while maintaining high thermal insulation, which provides an effective thermal runway mitigation strategy for rechargeable lithium-ion batteries. The nanoengineering strategy reported here would shed light on achieving superthermal insulation of nanostructures for energy-critical applications.

Thermal insulation paint material is an energy-critical coating component for thermal management in energy-efficient buildings, vehicles, electronics, and data centers. Long-standing pursuits for the paint coating materials are high thermal insulation and light reflectance, mechanical durability, and wear resistance. Here we describe an aqueous-based hierarchical coating nanocomposite composed of mesoporous silica aerogel and titania nanoparticle pigment paint which exhibits a low thermal conductivity of 0.029 W/m K, a high visible reflectance of 90%, and a mechanical Young’s modulus of ∼4.86 MPa with a high abrasion resistance. The hierarchical and hydrophobic nanocomposite coatings show robust thermal cycling and thermal resistance, resulting in an equivalent cooling power of 928 W/m2. The design and manufacturing principle reported here could extend to a variety of insulation coating materials to achieve energy efficiency and sustainability.

Flexible electronics for harsh and hazardous environments could offer a broad range of technological applications from conformal structural health monitoring, hypersonics, to telecommunication systems. However, advanced materials with the capability of additive manufacturing and the tolerance to extreme operating conditions are imperative. Here, we report hightemperature radiofrequency electronics with thermal management by printing copper hybrid conductors onto flexible thin alumina ribbon ceramic and ceramic fiber/silica aerogel composite. Regulating thermal stability, tuning resonance frequency, and increasing current-carrying ability of printed electronics are synergistically achieved using a flexible thermal-insulation ceramic fiber/silica aerogel composite or thermally conductive alumina ribbon ceramic substrates and high-temperature copper−graphene conductors. The printed copper conductor coatings exhibit tunable antenna resonance and electromagnetic interference effectiveness of 70 dB at a thickness of 5 μm, opening a pathway toward flexible hybrid radiofrequency electronics with thermal management.