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Global population growth and industrialization have exacerbated the nonrenewable energy crises and environmental issues, thereby stimulating an enormous demand for producing environmentally friendly materials. Typically, biomass-based aerogels (BAs), which are mainly composed of biomass materials, show great application prospects in various fields because of their exceptional properties such as biocompatibility, degradability, and renewability. To improve the performance of BAs to meet the usage requirements of different scenarios, a large number of innovative works in the past few decades have emphasized the importance of micro-structural design in regulating macroscopic functions. Inspired by the ubiquitous random or regularly arranged structures of materials in nature ranging from micro to meso and macro scales, constructing different microstructures often corresponds to completely different functions even with similar biomolecular compositions. This review focuses on the preparation process, design concepts, regulation methods, and the synergistic combination of chemical compositions and microstructures of BAs with different porous structures from the perspective of gel skeleton and pore structure. It not only comprehensively introduces the effect of various microstructures on the physical properties of BAs, but also analyzes their potential applications in the corresponding fields of thermal management, water treatment, atmospheric water harvesting, CO2 absorption, energy storage and conversion, electromagnetic interference (EMI) shielding, biological applications, etc. Finally, we provide our perspectives regarding the challenges and future opportunities of BAs. Overall, our goal is to provide researchers with a thorough understanding of the relationship between the microstructures and properties of BAs, supported by a comprehensive analysis of the available data. [ABSTRACT FROM AUTHOR]

Circularly polarized luminescence (CPL) has attracted broad interest due to its potential applications in advanced photonics and electronics. CPL is generally produced from chiral moiety-decorated π-conjugated molecules. Alternatively, CPL can be directly generated from achiral luminescent materials in helical and twisted supramolecular systems, which circumvents the tough and tedious syntheses in traditional methods. In particular, one-dimensional helical supramolecular systems in the fibrous morphology are superior for CPL generation over those in spheroidal or planar structures, because of their high dissymmetry factors (glum). Efforts on one side are focused on the development of helical luminescent fibers with high glum, and on the other side, are directed toward the arrangement of nanofibers to produce scalable materials (films or fibers) with chiral activity. This review summarizes the recent advances in CPL generation from supramolecular systems, illustrating how the chirality transfer, amplification, and regulation of CPL are achieved in fibrous morphologies. Their working mechanisms at hierarchical length scales, including helical fibrous supramolecular assemblies at the nanoscale, chiral films constructed using helically arranged nanofibers at the microscale, and macroscopic fibers via mechanical twisting, are described sequentially. Finally, the current challenges and future opportunities of the chiral systems are also presented. [ABSTRACT FROM AUTHOR]

Fibers have played a critical role in the long history of human development. They are the basic building blocks of textiles. Synthetic fibers not only make clothes stronger and more durable, but are also customizable and cheaper. The growth of miniature and wearable electronics has promoted the development of smart and multifunctional fibers. Particularly, the incorporation of functional semiconductors and electroactive materials in fibers has opened up the field of fiber electronics. The energy supply system is the key branch for fiber electronics. Herein, after a brief introduction on the history of smart and functional fibers, we review the current state of advanced functional fibers for their application in energy conversion and storage, focusing on nanogenerators, solar cells, supercapacitors and batteries. Subsequently, the importance of the integration of fiber-shaped energy conversion and storage devices via smart structure design is discussed. Finally, the challenges and future direction in this field are highlighted. Through this review, we hope to inspire scientists with different research backgrounds to enter this multi-disciplinary field to promote its prosperity and development and usher in a truly new era of smart fibers. [ABSTRACT FROM AUTHOR]

Building nanocomposite architectures based on carbon nanotubes (CNTs) and active nanoparticles (NPs) with an engineered interface is of great interest for developing the ability to store electrochemical energy. The use of cellulose to direct hetero-assembly was achieved by in situ regenerating an ionic liquid mixture (CNTs, NPs, cellulose) in water, and was applied to the fabrication of flexible anodes consisting of CNTs and NPs. These anodes showed CNTs threading through their structures and exhibited strong interfacial contacts, which provided a relatively short lithium-ion diffusion length and continuous electron conduction pathway as well as high mechanical stability. When evaluated as an anode material for a lithium-ion battery, the flexible nanocomposites showed high reversible capacity and good rate performance compared to traditionally made electrodes, demonstrating a simple and green strategy for the industrial-scale production of energy-storage devices. [ABSTRACT FROM AUTHOR]

Manipulating thermal transport across hard/soft material interfaces is important for composites which are critical for a wide range of applications, including electronic packaging, thermal storage, sensors and medicine. To increase the interfacial thermal conductance (Gint), a previous strategy has focused on using a self-assembled monolayer (SAM) to bridge the phonon spectra mismatch between the materials constituting the interface. Here, we introduce a general strategy aiming for interfaces which are incompatible with the previous strategy. Copper (Cu) and epoxy resin are chosen as representative materials constituting the interface. The proposed strategy relies on using a strongly bonding SAM to covalently connect Cu and epoxy. The thermal measurements show that Gint can be enhanced by as much as 11 fold. An interesting result is found that the Cu/epoxy interface, modified with the SAM used in the previous strategy, shows approximate 2-fold lower Gint. Through a series of experiments, including tensile strength and wettability tests, the formation and characters of bonds in different interface systems are explored and understood. The correlation between bonding characters and Gint is also elucidated. We demonstrate that when the structure of the soft material is complex, interfacial thermal transport should be tuned by covalent bonds rather than by phonon spectra match. Finally, the great potential of the proposed strategy in manipulating the thermal properties of nanocomposites is illustrated here with a theoretical prediction. [ABSTRACT FROM AUTHOR]

Despite the huge progress of luminescent molecular assemblies over the past decade, it is still challenging to understand their confined behavior in semi-crystalline polymers for constrained space recognition. Here, we report a polymorphic luminogen with aggregation-induced emission (AIE), capable of selective growth in polymer amorphous and crystalline phases with distinct color. The polymorphic behaviors of the AIE luminogen embedded within the polymer network are dependent on the size of nano-confinement: a thermodynamically stable polymorph of the AIE luminogen with green emission is stabilized in the amorphous phase, while a metastable polymorph with yellow emission is confined in the crystalline phase. The information on polymer crystalline and amorphous phases is transformed into distinct fluorescence colors, allowing a single AIE luminogen as a fluorescent marker for visualization of polymer microstructures in terms of amorphous and crystalline phase distribution, quantitative polymer crystallinity measurement, and spatial morphological arrangement. Our findings demonstrate that confinement of the AIE luminogen in the polymer network can achieve free space recognition and also provide a correlation between microscopic morphologies and macroscopic optical signals. We envision that our strategy will inspire the development of other materials with spatial confinement to incorporate AIE luminogens for various applications., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Thin-film pseudocapacitor electrodes with ultrafast lithium storage kinetics, high capacitance and excellent cycling stability were fabricated from monodispersed TiO(2) building nanocrystals, providing a novel approach towards next-generation micro-supercapacitor applications., (This journal is © The Royal Society of Chemistry 2012)