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Stimuli-responsive hydrogels hold an irreplaceable statue in intelligent actuation materials because of their reversible stretchability and excellent biocompatibility. However, the poor mechanical performance and complicated fabrication process of anisotropic structures severely limit their further applications. Herein, we report a high-strength thermoresponsive wood-PNIPAM composite hydrogel actuator with complex deformations, through a simple in-situpolymerization. In this composite hydrogel actuator, the anisotropic wood and the thermoresponsive PNIPAM hydrogel hydroel can work together to provide bending and even other complex deformations. Owing to strong interfacial interaction, this actuator perfectly realized the combination of good mechanical properties (∼1.1 MPa) and fast actuation speed (∼0.9 s). In addition, by adjusting the orientation direction of wood, this actuator can achieve various complex deformations. Such composite hydrogel actuator could be a good candidate for intelligent applications, such as intelligent actuators, smart valves, manipulators and even soft robots.

Biomass and its derivatives, with their renewable characteristics, cost-effectiveness, and controllable structural and compositional properties, are promising precursors for carbon materials. Herein, N,O-codoped carbon aerogels were synthesized by carbonization and zinc nitrate activation of histidine. The specific surface area (SSA) was markedly increased with the addition of zinc nitrate, and the maximum value achieved 853 m2g–1for ZHC-11 obtained with the molar ratio of 1:1 between histidine and zinc nitrate. The D/G-band intensity ratio increased from 1.55 for the histidine-derived control sample HC to 1.65 for ZHC-11, indicating the enhancement of amorphous feature. The nitrogen content increased from 6.5% for HC to 1.60 for ZHC-11. The optimized microstructure and enriched heteroatom doping are beneficial to the capacitance performance. The optimum electrode exhibited 234.1 F g–1at 0.1 A g–1and maintained 116.5 F g–1at 60 A g–1in a three-electrode system. In particular, the symmetric supercapacitor showed 121.9 F g–1and 19.5 Wh kg–1at 0.2 A g–1. This research offers guidance on the cost-effective synthesis of carbon materials for supercapacitors, while also providing novel insights to realize the complete utilization of biomass derivatives.

La2O3–CeO2–Fe3O4composite nanofibers (LCF NFs) were fabricated via a facile electrospinning - calcination approach, and evaluated as an adsorbent for defluoridation from aqueous solution under batch mode. The pseudo-second-order (PSO) model described defluoridation characteristics well under 20 and 50 mg/L. F−adsorption under 288.15–308.15 K obeyed the Langmuir adsorption isotherm better with the maximum uptakes of 202.43–229.89 mg/g, respectively. The obtained thermodynamics constants involving Gibbs free energies change (ΔG < 0), enthalpy (ΔH9.90 kJ/mol), and entropy (ΔS56.63 J/mol/K) unveiled that the defluoridation process was spontaneous natural as well as endothermic. After four repeated cycles, the developed LCF11 NFs revealed favorable regeneration ability, indicating that LCF11 NFs are auspicious and stable candidates for defluoridation of wastewater.