The design of hierarchical structures from biomass has become one of the hottest subjects in the field of microwave absorption due to its low cost, vast availability and sustainability. A kapok-fiber-derived carbon microtube was prepared by facile carbonization, and the relation between the structure and properties of the carbonized kapok fiber (CKF) was systematically investigated. The hollow tubular structures afford the resulting CKF composites with excellent microwave-absorbing performance. The sample with a 30 wt.% loading of CKF in paraffin demonstrates the strongest microwave attenuation capacity, with a minimum reflection loss of −49.46 dB at 16.48 GHz and 2.3 mm, and an optimized effective absorption bandwidth of 7.12 GHz (10.64–17.76 GHz, 2.3 mm) that covers 34% of the X-band and 96% of the Ku-band. Further, more than 90% of the incident electromagnetic wave in the frequency from 4.48 GHz to 18.00 GHz can be attenuated via tuning the thickness of the CKF-based absorber. This study outlines a foundation for the development of lightweight and sustainable microwave absorbers with a high absorption capacity and broad effective absorption bandwidth.

Sensors, as one of the crucial components of wearable electronics, have attracted much attention due to their extensive application in healthcare, human–machine interfaces, electronic skins (E-skins), rehabilitation, and internet of things. However, there is still a challenge to fabricate flexible strain sensors with both good sensitivity and large working strain range. Herein, a facile, scalable, and low-cost strategy is developed to prepare highly sensitive strain sensors based on natural rubber foam and Ti₃C₂T_x nanosheeets (MXene/NR) by dip-coating method. The fabricated MXene/NR composite exhibits excellent strain sensitivity and large strain range. The gage factor of the MXene/NR composite reaches 14 in the strain range of 0–5% with a low pressure limitation of detection (435 Pa). Additionally, the sensing range is as large as 0–80% of strain and shows good stability during the pressing and relaxing cycles. It is demonstrated that the MXene/NR composite could be used to detect motions, such as finger pressing and step monitoring, suggesting it is a promising candidate for fabricating wearable electronics.

This study details microwave-absorbing materials made of natural rubber/nitrile butadiene rubber (NR/NBR) blends with multi-walled carbon nanotubes (MWCNTs) and molybdenum disulfide (MoS₂). The mechanical blending method and the influences of fabrication on the morphology and microwave-absorbing performance of resulting compounds were logically investigated. It was found that interfacial differences between the fillers and matrix promote the formation of MWCNTs and MoS₂ networks in NR/NBR blends, thus improving microwave-absorbing performance. Compared with direct compounding, masterbatch-based two-step blending is more conducive to forming interpenetrating networks of MWCNTs/MoS₂, endowing the resulting composite with better microwave attenuation capacity. Composites with MWCNTs in NR and MoS₂ in NBR demonstrate the best microwave-absorbing performance, with a minimum reflection loss of −44.54 dB and an effective absorption bandwidth of 3.60 GHz. Exploring the relationship between morphology and electromagnetic loss behavior denotes that such improvement results from the selective distribution of dual fillers, inducing networking and multi-component-derived interfacial polarization enhancement.

Addressing the environmental challenges posed by oil spills and industrial wastewater is critical for sustainable development. Graphene aerogels demonstrate significant potential as highly efficient adsorbents due to their high specific surface area, excellent structural tunability and outstanding chemical stability. Among available fabrication methods, the hydrothermal self-assembly technique stands out for its low cost, high tunability and good scalability. However, brittleness caused by stacking and agglomeration of graphene layers during self-assembly remains a significant challenge. In this study, we present a green and efficient self-assembly strategy combining a one-step hydrothermal process with a solution immersion method to fabricate a PDMS-coated epoxidized natural rubber–graphene composite aerogel (P@EGA). The resulting aerogel exhibits a high specific surface area (482.362 m² g⁻¹), hierarchical pore distribution from microporous to macroporous, ultra-low density (0.0104 g cm⁻³) and excellent hydrophobicity (contact angle = 147.6°). Remarkably, it retains 97.54% of its compressive stress after 50 compression-release cycles at 80% strain and quickly recovers its shape under a 500 g load. The P@EGA aerogel demonstrates outstanding adsorption capacities (65.37–132.75 g g⁻¹) for various oils and organic solvents, complete oil absorption in 0.4 seconds, and effortless regeneration through simple squeezing. Furthermore, its dual functionality in gravity-driven and powered water–oil separation systems underscores its broad application potential in environmental remediation.