High performance electrospun nanofibers could be used to fabricate nanofiber reinforced composites.

The rapid development of modern industry and excessive consumption of petroleum‐based polymers have triggered a double crisis presenting a shortage of nonrenewable resources and environmental pollution. However, this has provided an opportunity to stimulate researchers to harness native biobased materials for novel advanced materials and applications. Nanocellulose‐based aerogels, using abundant and sustainable cellulose as raw material, present a third‐generation of aerogels that combine traditional aerogels with high porosity and large specific surface area, as well as the excellent properties of cellulose itself. Currently, nanocellulose aerogels provide a highly attention‐catching platform for a wide range of functional applications in various fields, e.g., adsorption, separation, energy storage, thermal insulation, electromagnetic interference shielding, and biomedical applications. Here, the preparation methods, modification strategies, composite fabrications, and further applications of nanocellulose aerogels are summarized, with additional discussions regarding the prospects and potential challenges in future development.

Increased energy consumption stimulates the development of various energy types. As a result, the storage of these different types of energy becomes a key issue. Supercapacitors, as one important energy storage device, have gained much attention and owned a wide range of applications by taking advantages of micro-size, lightweight, high power density and long cycle life. From this perspective, numerous studies, especially on electrode materials, have been reported and great progress in the advancement in both the fundamental and applied fields of supercapacitor has been achieved. Herein, a review of recent progress in carbon materials for supercapacitor electrodes is presented. First, the two mechanisms of supercapacitors are briefly introduced. Then, research on carbon-based material electrodes for supercapacitor in recent years is summarized, including different dimensional carbon-based materials and biomassderived carbon materials. The characteristics and fabrication methods of these materials and their performance as capacitor electrodes are discussed. On the basis of these materials, many supercapacitor devices have been developed. Therefore, in the third part, the supercapacitor devices based on these carbon materials are summarized. A brief overview of two types of conventional supercapacitor according to the charge storage mechanism is compiled, including their development process, the merits or withdraws, and the principle of expanding the potential range. Additionally, another fast-developed capacitor, hybrid ion capacitors as a good compromise between battery and supercapacitor are also discussed. Finally, the future aspects and challenges on the carbon-based materials as supercapacitor electrodes are proposed.

Polyphenols are a class of ubiquitous compounds distributed in nature, with fascinating inherent biocompatible, bioadhesive, antioxidant, and antibacterial properties. The unique polyphenolic structures based on catechol or pyrogallol moieties allow...

Recently, the development of polydopamine (PDA) has demonstrated many excellent performances such as free radical scavenging, UV shielding, photothermal conversion, and biocompatibility. These unique properties make PDA widely designed as...

2850 wileyonlinelibrary.com large amounts of liquids and are excellent fi lters. Sponges with a volume of 1000 cm 3 can process up to 3000 L water h −1 . Furthermore, they can conduct light as discovered recently by Brümmer et al. [ 2 ] In addition, Natalio et al. reported on the formation of sponge skeletons shown to feature great bending strength and on the role of silicatein-α in the biomineralization of silicates in sponges, which accounts for the high reversible compressibility of sponges in spite of low densities. [ 3 ] Aizenberg et al. pointed out on the example of the so-called glass sponges ( Euplectella ) the important role of the hierarchical design from the nanometer to macroscopic length scale for structural materials. [ 4 ] The structural base of sponges are multiarmed spicules of silicate or calcium carbonate, which form highly porous structures of several hierarchical layers as shown in Figure 1 A,B. This leads to highly porous ultralight 3D materials (ultralight is defi ned when the density of material is <10 mg cm −3 ).[ 5 ] In recent literature, a variety of highly porous ultralight 3D materials were reported based on carbon, ceramics, and cellulose, which were characterized by porosities >99% and relatively high compressive strength. [6][7][8][9][10] Carbon and cellulose based sponges show ultralow densities and excellent mechanical properties but soft sponges with similar mechanical integrity are missing.Since spicules of natural sponges conspicuously resemble polymer fi bers, formation of such fi brous structures by electrospinning [ 11 ] could be a promising concept for the preparation of polymer-based biomimetic analogous of natural sponges and would open the huge potential of electrospun materials for 3D sponge-type structures. Indeed, 3D porous structures were prepared by electrospinning which was nicely summarized in comprehensive review in recent literature. [ 7 ] However, previous efforts of making 3D highly porous electrospun materials, for example, via ultrasonic treatment, resulted in higher densities and correspondingly lower porosities of <99%, [ 12 ] as well as relatively poor mechanical performance. Remarkably, Eichhorn et al. claimed that theoretically ultrahigh porosities of electrospun nonwovens >99% could not be achieved. [ 13 ] In contrast to these reports, we present here the formation of ultralight weight highly porous 3D electrospun polymer fi ber-based spongy structures with densities as low as 2.7 mg cm −3 corresponding to a porosity of 99.6%. They were prepared by electrospinning of a photo cross-linkable polymer followed by UV cross-linking, mechanical cutting, suspending cut fi bers in liquid dispersion, and freezedrying. These polymer sponges showed in analogy to natural Ultralight, Soft Polymer Sponges by Self-Assembly of Short Electrospun Fibers in Colloidal DispersionsGaigai Duan , Shaohua Jiang , Valérie Jérôme , Joachim H. Wendorff , Amir Fathi , Jaqueline Uhm , Volker Altstädt , Markus Herling , Josef Breu , Ruth Freitag , Seema Agarwal , and Andreas Gre...

A solar steam generation method has been widely investigated as a sustainable method to achieve seawater desalination and sewage treatment. However, oil pollutants are usually emitted in real seawater or wastewaters, which can cause serious fouling problems to disturb the solar evaporation performance. In this work, a mussel-inspired, low-cost, polydopamine-filled cellulose aerogel (PDA-CA) has been rationally designed and fabricated with both superhydrophilicity and underwater superoleophobicity. The resulting PDA-CA device could also achieve a high solar evaporation rate of 1.36 kg m–1 h–1 with an 86% solar energy utilize efficiency under 1 sun illumination. In addition, the PDA-CA not only exhibited promising antifouling capacity for long-term water evaporation but also engaged in the effective adsorption of organic dye contaminants. These promising features of PDA-CA may offer new opportunities for developing multifunctional photothermal devices for solar-driven water remediation.

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