Solar energy-facilitated materials are promising to solve energy problems by converting clean solar energy to thermal energy. However, heat loss of photothermal materials still limits the photothermal conversion phenomenon. Herein, we designed bio-inspired hollow carbon microtubes (HCMTs) by one-step carbonization of renewable cotton fibers, which can avoid the complex preparation procedures of the template method. Similar to polar bears, the hollow construction can efficiently reduce heat loss, which improves the utilization of light and photothermal property. The HCMTs can be applied on a variety of substrates to obtain multifunctional photothermal protective coatings. The temperature of the coating can rapidly warm up to 97.7 °C under 1 kW/m 2 sun irradiation. In addition, the coatings show excellent superhydrophobic property (CA of 161.5 ± 0.9°), which can prevent the adhesion of the contaminant and maintain the long-time photothermal property of the surface. Also, the coating is able to withstand sandpaper abrasion, repeat tape-peeling, and tribological friction without losing superhydrophobic properties, indicating remarkable mechanical stability. Furthermore, the coating can withstand high-temperature calcination (400 °C), long-time UV radiation, and corrosive liquid erosion, which exhibits prominent chemical stability. More importantly, the combination of active deicing and passive antiicing of the coating can effectively prevent the formation and accumulation of ice on the surface. The outstanding environmental adaptability can greatly extend its lifespan and meet the long-term service conditions.

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.

High-performance electromagnetic interference (EMI) shielding and thermal management materials with ultraflexibility, high strength, outstanding stability under mechanical deformation, and low cost are urgently demanded for modern integrated electronic and telecommunication systems. However, the creation and application of such desirable materials is still a potent challenge. Herein, we develop such a high-performance multifunctional multilayer composite, known as vertically aligned carbon nanotube@graphene paper/polydimethylsilane (VACNT@GP/PDMS), which involves the in situ growth of VACNTs onto GPs, vertical stacking of VACNT@GP layers, and infiltration of PDMS. The EMI shielding and mechanical properties of multilayer composites can be dramatically increased by increasing the number of VACNT@GP layers. Benefiting from the conduction loss in highly conductive GPs and polarization of huge VACNT–PDMS–VACNT microcapacitor networks, the multilayer composite with four VACNT@GP layers exhibits a superior EMI SE of 106.7 dB over a broad bandwidth of 32 GHz, covering the entire X-, Ku-, K-, and Ka-bands, which far suppresses the values of most of the reported EMI shielding materials. Moreover, the multilayer composites show excellent thermal management performance such as a high Joule-heating temperature at low supplied voltages, rapid response time, and sufficient heating stability. In addition, remarkable flexibility, high tensile strength (up to 13.4 MPa), and super stability under mechanical deformation (nearly no EMI SE degradation after repeatedly bending 10,000 times) are also discovered. These excellent comprehensive properties, along with the ease of low-cost mass production, pave the way for the practical applications of multilayer VACNT@GP/PDMS composites in EMI shielding and thermal management.

Because of the high synthesis cost, strong chemical inertness, complex process, and easy to endanger environment of traditional carbon-based nanolubricant additives, the development of its application in lubrication is limited. Therefore, a new type of lubricant additive with low cost, high yield, high performance, and environmental protection is urgently needed. Herein, a kilogram-scale carbon dots (CDs) lubricant additive was prepared by a simple and green one-step reaction of aldol condensation, which showed excellent lubricating properties in water and sunflower oil. The tribological properties of the CDs lubricant additive at different concentrations, loads, and speeds were systematically studied. The results show that the average friction coefficient of water is significantly reduced by 75% by a CDs lubricant additive. In particular, CDs not only exhibited excellent service life and lubrication stability during friction but also kept the friction coefficient change rate of sunflower seed oil close to 0 within 500 min. According to the tribological evaluation and wear surface analysis, the lubrication mechanism of CDs was attributed to their own morphological characteristics and abundant oxygen-containing functional groups on the surface. In the friction process, the charge adsorption effect, the adsorption protective film, and the hydrogen bonding layer are generated, which play an essential role in obvious antiwear and friction reduction. Therefore, this work provides a reference for the preparation of high-performance and high-yield lubricant additives.

To realize the application potential of molybdenum disulfide (MoS 2 ) in aqueous environments, scalable and efficient methods for the preparation of high-concentration and stable dispersions need to be developed. In this paper, ultrathin MoS 2 successfully was synthesized using an in situ-exfoliated bulk MoS 2 method in water using ionic liquid crystals (ILCs) as green exfoliating/dispersing agents. The ILCs containing hydrophobic cations and hydrophilic anions not only help to exfoliate bulk MoS 2 into ultrathin MoS 2 nanosheets but also prevent the reagglomeration of the ultrathin MoS 2 nanosheets in water. MoS 2 nanosheets were confined by the ILCs through π−π and C−H•••π interactions, preventing direct contact of MoS 2 with water. The ILC−MoS 2 dispersion exhibited remarkable dispersion stability exceeding 8 months at room temperature. Moreover, the ILC−MoS 2 dispersion has been successfully proven to be an excellent water-based lubricant, where the ILCs form a lubricant film on the friction surface through electrostatic interactions and MoS 2 increases the load-bearing capacity of the lubricant film due to its high modulus, resulting in an 84.9% reduction in the coefficient of friction compared to pure water. The method is expected to provide a new idea for the preparation and application of MoS 2 .