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In recent years, the development of multi-functional supercapacitors with high flexibility and strong environmental adaptability has gradually become a focus of attention.

Recently, cellulose liquid crystals (LCs) have received attention due to their unique photophysical properties. However, their fragility and single structural color mode (birefringence) restricts their further development. Herein, a flexible optoelectronic LC film was reported composed of carbon quantum dots (CQDs) and cellulose nanocrystals (CNCs) produced by evaporation-induced self-assembly (EISA). Due to weak interactions between CQDs and CNCs, the optimal tensile strength and curvature reached 65.5 MPa and 2×102, respectively, thereby solving the fragility of LC films. In addition, these products retained not only the structural color of cellulose LC in the birefringent mode, but also introduced fluorescence in the CQD ultraviolet excitation mode. This was conducive for improving anticounterfeiting performance. Related work also addressed the issue of cellulosic LC fragility and provided a new method.

Premature ovarian insufficiency (POI) is a disease that seriously affects women's reproductive function and even leads to lifelong infertility. Little is known about the mechanism of lipopolysaccharide (LPS)-induced ovarian dysfunction. Thus, we aimed to identify the role of the up-regulation of microRNA (miRNA)-146 expression offered protection against ovarian dysfunction by inhibiting the toll-like receptor (TLR) 4, TLR4/phosphorylated (p)-nuclear factor (NF)-κB signaling pathway and inflammatory cytokine tumor necrosis factor (TNF)-a and Interleukin (IL)-6. In an in vivo study, we established an LPS-induced ovarian dysfunction mouse model. The mouse ovarian granulosa cells were transfected with miR-146 mimic or negative controls or inhibitor and then treated with LPS. Therefore, cell viability, cells apoptosis, IL-6 and TNF-a, TLR4, NF- κB were assessed, respectively. These results demonstrated that the up-regulation of miRNA-146 expression may protect against LPS-induced ovarian dysfunction and markedly increased the cell viability, and significantly reduced the ovarian granulosa cells apoptotic rate, and down-regulated IL-6 and TNF-a expression. In addition, miRNA-146 exerted protective ovarian functions might be via inhibiting TLR4/NF-κB signaling pathway. In summary, we reveal the up-regulation of miRNA-146 expression mitigated ovarian dysfunction by negatively regulating expression of the IL-6 and TNF-a, which may shed light on the potential molecular mechanisms of overexpression of miRNA-146 may reversed the ovarian dysfunction by inhibiting the TLR4/ NF-κB signaling pathway.

With the rapid development of science and technology, paper-based functional materials have become the core of the field of new materials. Recently, they have received extensive attention in the field of energy storage due to their advantages of rich and adjustable porous network structure, good flexibility. As an important energy storage device, paper-based supercapacitors have important application prospects in many fields, and have also received extensive attention from researchers in recent years. At present, researchers have modified and regulated paper-based materials by different means such as structural design and material composition to enhance their electrochemical storage capacity. The development of paper-based supercapacitors provides an important direction for the development of green and sustainable energy. Therefore, it is of great significance to summarize the relevant work of paper-based supercapacitors for their rapid development and application. In this review, the recent research progress of paper-based supercapacitors based on cellulose was summarized in terms of various cellulose-based composites, preparation skills and electrochemical performance. Finally, some opinions on the problems in the development of this field and the future development trend were proposed. It is hoped that this review can provide valuable references and ideas for the rapid development of paper-based energy storage devices.

As a green and sustainable natural resource, wood is regarded as a feasible candidate material for developing green and sustainable energy due to its natural porous structure. However, the conductivity of wood is poor, which restricts its application in energy storage. In this research, a novel material with Li–Na metal compounds inserted into porous carbonized lignin free wood (PCLFW) as a bifunctional hybrid is synthesized. This material with a high specific capacitance, high power density and excellent electrocatalytic activity is synthesized. The final product shows a high specific capacitance of 255 F g−1, high energy density of 31.88 Wh kg−1 and power density of 3188 W kg−1. Moreover, after experiencing 5000 cycles, the specific capacitance is maintained at 239 F g−1 (capacitance retention of 93%). In addition, the hybrid exhibits excellent hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) activities in alkaline solution, with overpotentials of 349 mV (Tafel = 192 mV dec−1) and 484 mV (Tafel = 184 mV dec−1), respectively. Meanwhile, the hybrid also shows a larger initial and half-wave potentials of −0.12 V and −0.22 V, reflecting an outstanding oxidation-reduction reaction (ORR) property. In a word, this work provides a new idea for us to fabricate wood-based hybrid for high-performance energy storage devices and carbon-based catalysts.

Supercapacitors are favored by researchers because of their high power density, especially with the acceleration of people's life rhythm. However, their energy density, especially from the point of view of the whole energy storage device, is far lower than that of commercial batteries. In this work, a kind of customizable full paper-based supercapacitor device with excellent self-healing ability is fabricated by simple and low-cost screen printing, electropolymerization and dip coating methods. The resultant separator-free supercapacitor device exhibits both ultrahigh gravimetric and areal specific energy (power) densities of 39 Wh kg−1 (69 kW kg−1) and 692 μWh cm−2 (236 mW cm−2), achieving excellent supercapacitor performance. Notably, the addition of vitrimers endows the whole device with outstanding self-healing properties, which is helpful for enhancing the adaptability of the device to the environment. In addition, this kind of paper-based device also displays good photothermal and electromagnetic shielding performances. These striking features make paper matrix composites attractive in the fields of supercapacitors, medical photothermal treatment and electromagnetic shielding.

The importance of genetic or epi-genetic heterogeneity has been increasingly recognized, but it has been challenging to profile intracellular post-transcriptional targets with sufficient throughput and resolution at across large-scale tissue samples. This study describes a technique, Spectrum-FISH, for high-throughput, sequencing-free, and tissue-wide spatial profiling of various post-transcriptional targets in acute tissue sections with subcellular resolution. The platform uses a biochip with an array of vertically aligned nanoprobes to effectively extract intracellular molecules for downstream analysis in the coordinates of the large-scale of cells within a tissue slice. As a proof-of-concept, the Spectrum-FISH is used to profile the spatial dynamics of 24 miRNAs and 9 m6A-modified messenger RNAs (m6A-mRNA) in acute olfactory bulb (OB) slices of millimeter scale. The results showed potentially multiomics spatial heterogeneity for the examined post-transcriptional regulations in rodent OB, especially in the outer plexiform layer and granule layer, where highly correlated miRNAs and m6A-mRNAs groups were identified, indicating a potential cooperative involvement of different post-transcriptional regulations at these OB regions.

Cellulose nanofiber (CNF) materials have attracted increasing attention in the field of energy storage and sensing due to their flexibility, environmental protection and sustainability. However, CNF materials have poor conductivity and low utilization effciency, which limits their applications. Improving the conductivity and utilization efficiency of CNFs while retaining their advantages is of great significance for developing wide applications of biomass resources. In this work, noncarbonized CNF@graphene quantum dot (GQD) film with good flexibility was fabricated through a combination of electrolysis and liquid dispersion. The as-obtained hybrid film shows excellent electrochemical storage performance, mechanical properties and sensing characteristics. Specifically, the film presents a specific capacitance of 118 mF cm− 2 even at a ultrahigh scan rate of 1000 mV s− 1, and a high capacitance retention higher than 93% at different current densities after 5000 cycles. Additionally, the assembled supercapacitor based on the hybrid film possesses high power and energy density at the same time (782 mW cm− 2 and 596 µWh cm− 2). These results demonstrate that the hybrid film possesses excellent rate performance and cycle stability. In addition, the film is sensitive to movement of the human body.

Recently, rapid development of intelligent wearable electronic equipment has triggered great needs for flexible and lightweight portable energy storage systems. Here, we demonstrate a low-cost ($ 0.5 m-2) and low density carbonized facial tissue paper (FCP) for high-conductive NiCo2S4 nanotubes assisted novel ultra-flexible solid-state supercapacitors (SSCs). The hydrothermal synthesized FCP-900@NiCo2S4 electrodes in this paper only have a density of 5 mg cm−2 and show large specific capacitance of 3115 mF cm−2 at 2 mA cm−2. Based on the high performance of FCP-900@NiCo2S4 electrodes, the as assembled SSCs can deliver an energy density of 1.2 mWh cm−3, high power density of 58.16 mW cm−3. It also shows great bending-state capacitive performance with high capacitance retention after 5000 cycles, providing a new opportunity for developing high-performance flexible wearable energy storage devices.

Organic luminogens have extensive applications due to their unique photophysical properties. In recent years, nonconjugated organic luminogens, in contrast to traditional conjugated luminogens, have gained much attention because of their facile preparation, environmental friendliness, and biocompatibility. In this study, a new kind of nonconventional luminogen based on dynamic covalent cross-linked polyhydroxyurethane is reported for the first time. The new luminogen not only exhibits intrinsic strong fluorescent emission in the solid state but also possesses high mechanical properties along with good shape memory and self-healing properties. In addition, the new luminogens are synthesized from aliphatic polyfunctional cyclic carbonate and amines via a much more straightforward method, avoiding the use of toxic isocyanates. Investigations indicated that the intrinsic luminescence of the resultant luminogens was induced by the cross-linking of polymer chains and could be well tuned by controlling the degree of cross-linking. By taking advantage of the unique characteristics of the resultant polymer luminogens, we further developed a facile method, named "light-mediated ink-free screen printing", for anticounterfeiting paper fabrication. Different from traditional ink-based printing technology, the new method used UV-light instead of expensive security ink to encode anticounterfeiting information on natural cellulose paper. The anticounterfeiting information is stable under various wet conditions, showing promising applications in the fast-growing counterfeiting of pharmaceuticals, packaging, and the food industry.

Wood-based materials are attracting extensive attention for applications in energy storage due to their environmental friendliness and the presence of numerous channels in their structure. However, the poor conductivity and flexibility of wood restrict its application. Although some researchers have made several efforts to improve the conductivity of wood by carbonization, the wood-based materials become brittle instead of flexible. Moreover, the cycling stability of carbonized wood-based materials becomes very poor due to their falling off during the process of electrochemical energy storage. Herein, for the first time, a smart carbonized lignin-free wood (CLFW)@Ni–NiS/vitrimer(V) composite multifunctional material with good reshaping, shape-memory, and self-healing properties was designed and fabricated. When assembled to a symmetric supercapacitor, the resultant CLFW@Ni–NiS/V hybrid showed not only the high gravimetric, areal, and volumetric energy densities of 38 W h kg−1, 687 μW h cm−2, and 58 W h L−1 and simultaneously maintained the high power densities of 56 kW kg−1, 202 mW cm−2, and 39 kW L−1, but also significantly enhanced cycling stability, respectively. In addition, CLFW@Ni–NiS/V presented good ORR and strain sensor properties. These outstanding advantages highlight the huge potential of smart wood-based materials with variable, shape-memory, and self-healing properties for applications in supercapacitors, catalysts, and sensors.

Colored paper is an important industrial paper grade that has applications in various industrial sectors. The increase in coloring efficiency is a key in decreasing the use of dyes, thus can be considered as a "green" process concept; the coloring efficiency depends on the dye retention and dispersion. This work explores the use of nanocellulose, specifically, TEMPO-oxidized cellulose nanofibers (TOCNF), on the coloring efficiency of the preparation of colored paper. Two dyes (i.e. direct blue GL and reactive red 195 (RR195)) were used. Thanks to the large specific surface area and abundant active sites of TOCNF, its use largely improves the direct blue GL retention during the process. The coloring difference (∆E*

A new kind of biobased material named lignin-containing polyhydroxyurethane (LPHU) is prepared from bis(6-membered cyclic carbonate) (BCC), dimer fatty diamine, and lignin for the first time. The preparation strategy is isocyanate-free, solvent-free, and catalyst-free, representing a green and environmentally friendly method to access polyurethane (PU)/lignin composites. The resultant LPHUs possess dual networks: a dynamic covalent network and a hydrogen bonding network, exhibiting superior mechanical strength, high thermal stability, excellent reprocessability/recyclability, and smart properties such as shape memory and self-healing. Potential application investigations indicate that the resultant LPHUs can be not only used for smart packaging label fabrication for heat-sensitive commodities but also further combined with natural cellulose paper to prepare paper-based electromagnetic shielding materials with high mechanical performance.

Three-Dimensional (3D) porous graphene, a kind of carbon material with in-plane nanopores and hierarchical pores formed between graphene layers, have attracted tremendous interests in application of supercapacitors due to their large specific surface areas, superior conductivity, unique porous structures and diversified compositions. Combining the advantages from both porous materials and graphene, 3D porous graphene has been regarded as an idea scaffold to build hierarchical hybrid with comprehensive electrochemical energy storage performance by introducing other substances. In this review, we aim to summarize the recent advances in fabricating 3D pure self-supported graphene-based porous structures with micro-, meso-, and macro-porous features and investigate the structure–property relationships, and their application in supercapacitors are also discussed.

In this work, a high-performance electrode material has been fabricated by the incorporation of carbon nanotubes (CNTs) and polyaniline (PANI) on a carbon foams (CF) to improve its electrochemical performance. The microstructure and performance of as-prepared material was characterized in detail. Results showed that the resultant material exhibited a high gravimetric capacitance up to 467.1 F g−1, higher energy density of 104. 2 Wh kg−1 and power density of 3000 W kg−1 at a current density 3 A g−1 when the electrochemical doping time of PANI equals to 20 min. Furthermore, it appeared a good cycling stability with capacitance retention of 94.5% after 10000 cycles. The enhanced electrochemical performance can be attributed to the unique carbon nanostructure and synergistic effects of active materials CNTs and PANI. It indicates that this novel CF/CNTs/PANI-20 composite is a promising candidate for electrochemical capacitors.

In this work, reaction bonded silicon carbide (RBSC) brake composites reinforced by chopped carbon fibers (CCFs) were fabricated by pre-liquid dispersion (PLD), low-temperature compression molding (LTCM) and subsequent densification by liquid silicon infiltration (LSI). The effects of the CCF fraction and PLD process on microstructure, phase composition, compression strength, shear strength and tribological performance of the brake composites were evaluated in detail. Our results showed that the distribution of CCF within the brake composites can be improved substantially through the treatment of PLD process, leading to the lowest open porosity of 9.63% and highest buck density of 1.87 g/cm3 comparing to the composites without PLD. Meanwhile, due to the augment of the interfacial area between the CCF and matrix, the as-prepared brake composite with 20 vol% CCF showed a compression strength as high as 157.55 MPa and shear strength of 22.14 MPa. Moreover, after further graphitization, a highly reliable RBSC brake composite with suitable average friction coefficient (0.427) for braking was obtained via the synergistic effects of lubrication of formed graphite and grain-abrasion by SiC grains in spite of a relatively high mass wear rate. These results show that the CCF reinforced RBSC brake composite is a promising candidate for high performance and low-cost friction composite for the application in brake pads.

In this research, a kind of non-carbonized reduced graphene oxide (RGO)-cellulose nanofibers (CNF) film is constructed by a combination of filtration and chemical reduction. In the hybrid, RGO enhances conductivity of CNF, and CNF as an idea spacer not only prevents stacking of RGO but also gives the film good mechanical properties including mechanical strength and flexibility. The synergistic effect of both endows the film with good electrochemical storage performance and outstanding mechanical properties. The hybrid film can be directly assembled into a symmetrical supercapacitor that shows an outstanding cycle stability, excellent rate performance, good mechanical strength and flexibility. Moreover, the film presents a high specific capacitance of 120 mF cm− 2, energy density of 536 µWh cm− 2 (32 Wh kg− 1) and power density of 193 mW cm− 2 (53 kW kg− 1). Additionally, the film can be used as a substrate to graft other components.

Cellulosic materials are especially suitable for use in flexible electronic products because of their light weight, good tolerance, flexibility, and biodegradability. In this work, cellulose nanofibril/reduced graphene oxide (CNF/rGO) nanocomposites are prepared and the thermal properties of the nanocomposites are analyzed. A supporting column and 2D layered structure porous paper is obtained with CNF/rGO as the heat conduction skeleton, which shows excellent thermal conductivity. The results show that this novel CNF/rGO porous paper has an ultrahigh in-plane thermal conductivity of up to 16.30 W/m K when only 1 wt.% rGO is added in, demonstrating efficient thermal management performance of the CNF-based nanocomposites with low rGO loading. We believe that the development of thermal management techniques using CNFs and rGO for emergent energy storage devices will lead to efficient technologies, further easing our daily lives.

A new self-crosslinked composite hydrogel is prepared with chitosan (CS) and cationic guar gum (CGG), based on the imine and acetal chemistry for gelation. The CS/CGG hydrogel exhibits thermal/pH responsiveness, injectability, adhesiveness and good compressive strength. The hydrogel is effective in removing phosphate from wastewater through an adsorption process, during which KH2PO4 is used as a phosphate model. The adsorption complies with the Freundlich model, indicating that it is a multilayered process with complex adsorption mechanisms. Considering their porous structure and nitrogen/phosphorus heteroatoms doping, the phosphate-adsorbed hydrogels are made into porous N,P doped carbon aerogels that can be potentially used as electrodes for a supercapacitor. The results indicate that these carbon aerogels possess excellent capacitive performance (best specific capacitance of 302.2 ± 4.9 F/g), as well as good cycling stability after 5000 times of charging/discharging.

In this work, a long-life and high-performance electrode material is successfully fabricated by the incorporation of carbon nanotube (CNT) with different length using chemical vapor deposition (CVD) on a hierarchically three dimensional (3D) carbon foam (CF), which is obtained from the mesophase pitch. The morphology, composition, and electrochemical performance of the as-prepared composites are characterized using the scanning electron microscope (SEM), Raman spectroscopy, X-ray diffraction (XRD) patterns, cyclic voltammetry, and galvanostatic charge/discharge cycling techniques. Characterizations suggest that this resultant CF/CNT-50 electrode material has a good cycling stability with capacitance retention of 96.5% even after 10000 cycles. Moreover, it shows a high mass capacitance of 227.5 F/g based on the resultant electrode materials, higher energy density of 28 Wh kg−1 and power density of 3700 W kg−1 at a current density 2 A g−1 and also excellent charge/discharge rate. These measured charge storage properties make the proposed hybrid materials excellent electrode material candidates for high performance supercapacitors.

C f /Ti 3 SiC 2 -SiC composites with different content of short carbon fibers were fabricated by the combination of compression molding and pressureless sintering. Microstructure and mechanical behavior of the composites were studied to evaluate the comprehensive performance of the material. In comparison, composites without carbon fibers were also fabricated in the same way. The results indicate that Ti 3 SiC 2 phases were synthesized in each cases and exhibit typical laminated structure with smooth surface. With the increase of carbon fiber content, composites turn from brittle to toughness, and show obvious elastic and no-linear regions on the force-displacement curve. Moreover, composite with 30% (volume fraction) carbon fiber shows the highest flexural strength (284.03 MPa), open porosity (15.78%), and lowest density (2.37 g cm −3 ). There were chemical reactions occurred between carbon fibers and matrix which formed strong covalent bonds and interfaces. The micrographs also reveal that fiber bridging and pulling-out are the most important reinforcement mechanisms which contribute to the mechanical properties of the composites.