Superelastic, Highly Conductive, Superhydrophobic, and Powerful Electromagnetic Shielding Hybrid Aerogels Built from Orthogonal Graphene and Boron Nitride Nanoribbons

Abstract

Three-dimensional (3D) elastic aerogels enable diverse applications but are usually restricted by their low thermal and electrical transfer efficiency. Here, we demonstrate a strategy for fabricating the highly thermally and electrically conductive aerogels using hybrid carbon/ceramic structural units made of hexagonal boron nitride nanoribbons (BNNRs) with in situ-grown orthogonally structured graphene (OSG). High-aspect-ratio BNNRs are first interconnected into a 3D elastic and thermally conductive skeleton, in which the horizontal graphene layers of OSG provide additional hyperchannels for electron and phonon conduction, and the vertical graphene sheets of OSG greatly improve surface roughness and charge polarization ability of the entire skeleton. The resulting OSG/BNNR hybrid aerogel exhibits very high thermal and electrical conductivity (up to 7.84 W m–1 K–1 and 340 S m–1, respectively) at a low density of 45.8 mg cm–3, which should prove to be vastly advantageous as compared to the reported carbonic and/or ceramic aerogels. Moreover, the hybrid aerogel possesses integrated properties of wide temperature-invariant superelasticity (from −196 to 600 °C), low-voltage-driven Joule heating (up to 42–134 °C at 1–4 V), strong hydrophobicity (contact angel of up to 156.1°), and powerful broadband electromagnetic interference (EMI) shielding effectiveness (reaching 70.9 dB at 2 mm thickness), all of which can maintain very well under repeated mechanical deformations and long-term immersion in strong acid or alkali solution. Using these extraordinary comprehensive properties, we prove the great potential of OSG/BNNR hybrid aerogel in wearable electronics for regulating body temperature, proofing water and pollution, removing ice, and protecting human health against EMI.

All-Nanochitin-Derived, Super-Compressible, Elastic, and Robust Carbon Honeycombs and Their Pressure-Sensing Properties over an Ultrawide Temperature Range

“…Moreover, even under a more severe compression strain of 90% over 10,000 cycles (Figure d), the carbon honeycomb exhibits stress and height retentions of up to 87 and 94%, respectively; the height reduction occurs mainly in the earlier cycles, and the structure becomes relatively stable in the subsequent cycles (Figure f). As summarized in Figure g, the carbon honeycomb reported herein can exhibit excellent elasticity and fatigue resistance favorably comparable to those of state-of-the-art carbon aerogels, such as fossil-derived carbon aerogels, ,,− MXene aerogels, and biomass-based carbon composite aerogels. ,,,− These results indicate the significance of the tailored microstructures and molecular structures within the carbon honeycomb.…”

High-Performance Microwave Absorption Materials: Theory, Fabrication, and Functionalization

“…21 Considering this, MAMs simultaneously possessing dielectric and magnetic loss (that is denoted as electromagnetic synergistic loss MAMs) are proposed and designed accordingly, which seem to achieve the goal of "thin, wide, light, strong" (that is thin thickness, effective absorption bandwidth coverage frequency, quality as far as light as possible, absorption of microwave ability). 22−24 Considering the more and more complex application environments and fields, 25 MAMs should be integrated with more functions to fulfill the ever-growing demands, including the functions of high temperature resistance, corrosion resistance, hydrophobicity, infrared stealth, self-healing, and etc. For example, MAMs with good hydrophobicity have many peculiarities, such as self-cleaning, corrosion protection, and ice protection, which are more durable in use.…”

“…Considering the more and more complex application environments and fields, MAMs should be integrated with more functions to fulfill the ever-growing demands, including the functions of high temperature resistance, corrosion resistance, hydrophobicity, infrared stealth, self-healing, and etc. For example, MAMs with good hydrophobicity have many peculiarities, such as self-cleaning, corrosion protection, and ice protection, which are more durable in use.…”

Superhydrophobic and Durable Silver-Coated Fabrics for Efficient Electromagnetic Interference Shielding

“…Superhydrophobic surfaces show considerable potential to improve the chemical stability of CPFCs, which isolates CPFCs from external corrosive conditions, allowing them to function stably in harsh environments. 30,31 Inspired by nature, numerous superhydrophobic faces have been fabricated by combining low surface energy materials and appropriate roughness created by nanoparticles (including ZnO, 32 SiO 2 , 33 and carbon nanotube 34 ). Owing to their unique physicochemical properties, superhydrophobic surfaces are widely utilized in self-cleaning, anti-icing, and anti-adhesion applications.…”