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Graphitic carbon nitride (g-C3N4) is a promising photocatalyst for CO2 reduction to alleviate the greenhouse effect. However, the low light absorption, small specific surface area, and rapid charge recombination limit the photocatalytic efficiency of g-C3N4. Herein, we demonstrate a bioinspired nanoarchitecturing strategy to significantly improve the light harvesting and charge separation of the g-C3N4/Au composite, as proven by the remarkable photocatalytic CO2 reduction. Specifically, a biotemplating approach is employed to transfer the sophisticated hierarchical structures and the related light-harvesting functionality of Troides helena butterfly wings to the g-C3N4/Au composite. The resulting g-C3N4/Au composite shows high photocatalytic efficiency under UV–visible excitation with triethanolamine as the sacrificial agent. The yields of CO and CH4 are 331.57 and 39.71 μmol/g/h, respectively, which are ∼36 times and ∼88 times that of pure g-C3N4 under the same conditions. Detailed experiments and the finite-difference time-domain method suggest that the superb photocatalytic activity should be ascribed to the unique periodic hierarchical structure which assists the light absorption and the localized surface plasmon resonance for promoted charge separation in addition to the more effective CO2 diffusion and larger specific surface area. Our work provides a new path for the design and optimization of photocatalysts based on biological structures that are usually unattainable artificially.

Compared with traditional paper relying on cellulose, the polymeric paper written by light can satisfy more multi‐environmental stability and reusability for sustainable development. Herein, proposed for the first time, a novel multifunctional polymeric paper with a patch‐sewing structure is designed, presenting the reversible writing/re‐writing performance. Meanwhile, a series of Fe‐based oxides with various submicron structures inherited from metal–organic framework templates are reported, in which the optimum one exhibited 95.04% absorbance from the finite difference time domain simulation and realized photothermal conversion instantaneously (soaring to 300 °C within 38 s). Given the distinguished mechanical properties (the tensile strength of 21.34 MPa and elongation at break of 546.06%), shape‐memory ability, and multi‐environmental stability, the composites are perfect for information recording. Due to the addition of the liquid crystal phase serving as the ink on the paper, the stress concentration and destruction can be recorded on the surface while it can recover to the initial situation by near‐infrared irradiation. Moreover, the remote writing with precision triggered by a focused light source can be achieved in multiple situations (air, water, and ice), which paved the way for the next generation of paper, especially in extreme conditions like deep‐water or aerospace.

Electrosorption is a novel desalination technique that has many advantages in the treatment of sewage. However, commercially available activated carbon electrodes for electrosorption commonly have low microporosity, poor moulding performance, and low adsorption and regeneration efficiency. Here, we evaluated a novel adsorbent material, activated carbon fibre felt (ACFF), for electrosorption of chromium ions (Cr6+) in sewage treatment. The ACFF was modified with 20% nitric acid and its modified structure was characterized. The modified ACFF was used as an adsorbing electrode to investigate its desalination effect by electrosorption. Results showed that compared with those of unmodified ACFF, the modified ACFF had more carbonyl and carboxyl groups and the specific surface area, average pore size and micropore volume of the modified ACFF also improved by 32.2%, 2.5% and 23.1%, respectively. The kinetics of Cr6+ adsorption conformed to the pseudo-second-order kinetic equation, and the adsorption isotherm conformed to the Langmuir model. In addition, the regeneration rate of the modified ACFF electrode was more than 94%. In conclusion, the modified ACFF exhibits excellent electrosorption and regeneration performance for Cr6+ removal from water and thus is of great value for promotion in sewage treatment.

A new fractal model for predicting the permeability of satin fabrics is proposed mainly based on the fractal theory. The repetitive unit was selected first according to the structural characteristic of a fabric. Then, the tortuosity fractal dimension was figured out after the actual length of a pore channel calculated by the minimum potential energy method. The maximum equivalent diameter, on which the structure fractal dimension can be computed depends, was obtained later by the microscopic measurement technique. Subsequently, the permeability was expressed as the explicit equation of various structural parameters, such as the representative length, the tortuosity fractal dimension, and the structure fractal dimension, which makes the physical meanings of each parameter intuitive and clear. Finally, the permeability of a five-harness fabric and an eight-harness fabric was predicted according to the new fractal models. In order to validate the new model, contrast experiments were designed. The results show that the predicted values agree well with the experimental values, which illustrate that the new method is feasible and effective.

Lepidopteran scales exhibit exquisite architectures that produce complex optical performance, such as structural colors for multiple survival strategies. However, how do these optical properties evolve to achieve such an excellent performance remains enigmatic because of the rarity of fossils and complexity of the gene regulatory network. Here, inspired by the primitive lepidopteran fossils, it is deduced that the morphology of these multilayered scales can be expressed by the basic trigonometric function sin(x) = t. A unified evolving model (UEM) is developed to reconstruct the evolutionary process from original multilayers to the current lepidopteran scale microstructures. The simulated optical response results show that factors such as the light absorption, warning coloration, and visual range intensity are optimized for survival by these insect individuals. The UEM provides a route to rationalizing other natural periodic microstructures. Furthermore, microstructure parameterization can facilitate the design of the nano‐optical materials. Corresponding results can help develop specific applications such as photothermal conversion, radiative cooling, and camouflaging.

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