It is highly desirable to develop green and renewable structural materials from biomaterials to replace synthetic materials involved from civil engineering to aerospace industries. Herein, we put forward a facile but effective top–down strategy to convert natural bamboo into bamboo steel. The fabrication process of bamboo steel involves the removal of lignin and hemicellulose, freeze-drying followed by epoxy infiltration, and densification combined with in situ solidification. The prepared bamboo steel is a super-strong composite material with a high specific tensile strength (302 MPa g–1 cm3), which is higher than that (227 MPa g–1 cm3) of conventional high specific strength steel. The bamboo steel demonstrates a high tensile strength of 407.6 MPa, a record flexural strength of 513.8 MPa, and a high toughness of 14.08 MJ/m3, which is improved by 360, 290, and 380% over those of natural bamboo, respectively. Particularly, the mechanical properties of the bamboo steel are the highest among the biofiber-reinforced polymer composites reported previously. The well-preserved bamboo scaffolds assure the integrity of bamboo fibers, while the densification under high pressure results in a high-fiber volume fraction with an improved hydrogen bonding among the adjacent bamboo fibers, and the epoxy resin impregnated enhances the stress transfer because of its chemical crosslinking with cellulose molecules. These endow the bamboo steel with superior mechanical performance. Furthermore, the bamboo steel demonstrates an excellent thermal insulating capability with a low thermal conductivity (about 0.29 W/mK). In addition, the bamboo steel shows a low coefficient of thermal expansion (about 6.3 × 10–6 K–1) and a very high-dimensional stability to moisture attack. The strategy of fabricating high-performance bamboo steel with green and abundant natural bamboo as raw materials is highly attractive for the sustainable development of structural engineering materials.

Developing wearable strain sensors with zero temperature coefficient of resistance (TCR), which is crucial to overcome the problem of temperature disturbance, has been scarcely studied. Herein, highly stretchable graphene nanoplatelet...

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This work reports a flexible yet robust Ti3C2Tx MXene/bamboo microfibril (BF) composite paper via a simple vacuum filtration process.

Ti3C2T x MXene has drawn remarkable attention in electronic sensors. Existing MXene-based pressure sensors generally have a narrow linear sensing range, which limits their wide application. Moreover, previous studies on MXene-based pressure sensors were mainly focused on increasing sensitivity via various microengineering techniques, but little attention has been paid to environmental stability and biocompatibility of these sensors. Herein, a highly flexible, biocompatible, and environmentally stable Ti3C2T x MXene/bamboo cellulose fiber (BCF)/poly­(dimethylsiloxane) (PDMS) composite pressure sensor with an ultrawide working range (up to 2 MPa), a high linearity (R 2 = 0.966), and long-term stability is demonstrated. First, the MXene/BCF (MB) foam with well-optimized porosity and connectivity was prepared through an efficient freeze-drying method. Then, the MB-based piezoresistive composite (PMB) was obtained by directly embedding the MB foams into PDMS elastomers. In striking contrast to previous MXene composite-based pressure sensors, the PMB pressure sensor exhibits not only excellent pressure sensing performance and good biocompatibility but also prominent work reliability to resist temperature fluctuation, moisture/water, and UV irradiation. Furthermore, to demonstrate the potential of the PMB pressure sensor, various human movements under both ambient and harsh environmental conditions were monitored. Finally, the PMB pressure sensor was also successfully integrated with soft robotic hands to show its great potential in robotic tactile sensation.