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All-solid-state lithium ion batteries (LIBs) are ideal for energy storage given their safety and long-term stability. However, there is a limited availability of viable electrode active materials. Herein, we report a truxenone-based covalent organic framework (COF-TRO) as cathode materials for allsolid-state LIBs. The high-density carbonyl groups combined with the ordered crystalline COF structure greatly facilitate lithium ion storage via reversible redox reactions. As a result, a high specific capacity of 268 mAh g À1 , almost 97.5 % of the calculated theoretical capacity was achieved. To the best of our knowledge, this is the highest capacity among all COF-based cathode materials for all-solid-state LIBs reported so far. Moreover, the excellent cycling stability (99.9 % capacity retention after 100 cycles at 0.1 C rate) shown by COF-TRO suggests such truxenone-based COFs have great potential in energy storage applications.

This work describes an all-biomass fluorescent hydrogel fabricated by functionalizing alginate (ALg) and cellulose nanofibers (CNF) hydrogels with fluorescent biomass carbon dots (CQDs) derived from glucose, xylose, and glucosamine. The biomass CQDs played dual functions in the composite hydrogels: first, endowing hydrogels with good fluorescent characters; second, enhancing the mechanical properties of hydrogels because of the cross-linking effect of the abundant oxygen-containing groups or amino groups on surface with ALg or CNF. The elastic modulus of ALg hydrogel and CNF hydrogel was increased by 4.7 times and 1.5 times, respectively, by the adding CQDs. As a proof of concept, ALg/CQDs-3 hydrogel and CNF/CQDs-3 hydrogel were used to detect Fe3+ ions and gold nanoparticle (AuNPs) in aqueous solution, showing high sensitivity. The prepared all-biomass fluorescent hydrogels hold great potential in biological imaging, biosensing, and biological monitoring fields.

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Cellulose-based green and sustainable materials with good mechanical properties, malleability, rehealability, and recyclability have been prepared from cellulose papers and a polyimine matrix.

The growing environmental concern over petrochemical-based plastics continuously promotes the exploration of green and sustainable substitute materials. Compared with petrochemical products, cellulose has overwhelming superiority in terms of availability, cost, and biodegradability; however, cellulose's dense hydrogen-bonding network and highly ordered crystalline structure make it hard to be thermoformed. A strategy to realize the partial disassociation of hydrogen bonds in cellulose and the reassembly of cellulose chains via constructing a dynamic covalent network, thereby endowing cellulose with thermal processability as indicated by the observation of a moderate glass transition temperature (T g = 240 °C), is proposed. Moreover, the cellulosic bioplastic delivers a high tensile strength of 67 MPa, as well as excellent moisture and solvent resistance, good recyclability, and biodegradability in nature. With these advantageous features, the developed cellulosic bioplastic represents a promising alternative to traditional plastics.

The increasingly serious environmental pollution caused by petroleum-based nondegradable plastics has evoked intense research interest in the development of sustainable and degradable bioplastics. Starch is one of the most promising biopolymers for the preparation of bioplastic. However, it is still a great challenge to develop starch bioplastics with high strength, low water sensitivity, and excellent water resistance. Herein, we reported a facile chemical modification method for the synthesis of a novel starch bioplastic. In this process, an easily available starch derivate, dialdehyde starch (DAS), is cross-linked using diamine based on dynamic imine chemistry to prepare DAS-based polyimine (DAS-PI). This DAS-PI exhibits excellent thermal malleability, and it can be easily thermoformed into novel starch bioplastic without using any plasticizer. The resulting starch bioplastic shows high mechanical strength (40.6 MPa), high thermal stability, and excellent water/chemical resistance, as well as heat-induced self-healing ability. Moreover, it can be easily chemically degraded and recycled. This work provides a novel method of producing high-performance starch bioplastics without using plasticizers.