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Biodegradable active food packaging addresses key environmental issues including plastic waste and food waste.

Fire retardancy for textiles is important to prevent the rapid spread of fire and minimize damage to property and harm to human life. To infer fire-resistance on textile materials such as cotton or nylon, chemical coatings are often used. These chemicals are usually toxic and economically and environmentally unsustainable, however, some naturally produced protein-based fire retardants could be an alternative. A biofilm protein from Bacillus subtilis (BslA) was identified and recombinantly expressed in Escherichia coli with a double cellulose binding domain. It was then applied to a range of natural and synthetic fabric materials. A flame retardancy test found that use of BslA reduced fire damage by up to 51% and would pass fire retardancy testing according to British standards. It is therefore a viable and sustainable alternative to current industrial fire-retardant coatings.

The mechanical measurements of nanostructures are crucial to the development and processing of novel nanodevices. In this study, TiO2 nanotubes were synthesised using an electrospinning method combined with subsequent heat treatment. A simple experimental method is established to measure the elastic modulus of a single nanotube based on atomic force microscopy (AFM) technology. Subsequently, the finite element method (FEM) is employed to evaluate the effect of the elastic modulus of TiO2 and dimensional size on the mechanical behaviours of the TiO2 nanotubes. The results show that, by combining AFM with FEM technology, the mechanical behaviour of a single TiO2 nanotube can be predicted efficiently in the linear elastic region.

Developing highly active catalysts for hydrogen evolution reaction is vital for large-scale and efficient production of hydrogen through water splitting. In this study, we reported scale-up TiO2/LaFeO3 composite catalysts with multiple heterojunctions synthesized via facile solid-phase reaction and investigated their hydrogen evolution reaction (HER) performance in both acidic and alkaline solutions. To be excited, under AM1.5 simulated sunlight irradiation, the working electrode decorated by TiO2/LaFeO3 presents a higher current density with 10 mV/cm2 at 0.55 V in a 0.5 M H2SO4 solution, suppressing the corresponding performance with the occasion of pure electrocatalysis. Importantly, the hydrogen evolution efficiency can reach 7.62 mmol h−1 cm−2, overwhelming approximately 5.3 times higher than that of commercial P25 (1.43 mmol h−1 cm−2) with exceptional stability via imposing simulated sunlight and a bias of 500 mV. Therefore, such excellent catalysts could serve as an alternative to reach remarkable HER performance via fossil fuels free technology, potentially making contribution toward the goal of global “carbon neutral” by 2050.

Climate change is accelerated by increasing food waste; more importantly, this pressing challenge is compounded by the environmentally damaging effects of conventional plastics used in food packaging. We have critically reviewed active release packaging as an innovative solution to address these concerning effects. Particular attention is paid to controlled release, encapsulation methods, and natural active agents. Other aspects of active packaging development such as stringent safety legislations are also discussed, alongside highlighting developmental hurdles. Certain technologies are underscored as revolutionary for the field of active packaging: in particular, stimuli-responsive materials, reliable controlled-release mechanisms, and the synergy of active packaging and intelligent packaging. Encapsulation is described as an important method of achieving controlled release. The potential of electrospun biopolymeric fibers to encapsulate natural antimicrobial or antioxidant molecules is also noted. Importantly, the review discusses the incorporation of nanomaterials and subsequent increased commercialization success due to the modulation of Bioplastic properties. In order to outcompete inexpensive petroleum-based plastics, these novel packaging materials must have good mechanical properties, good barrier properties, well-defined controlled release studies, and good biodegradation rates. Overall, it is evident that biopolymeric active-release packaging incorporating natural active compounds will serve as a high-potential, sustainable replacement for ubiquitous petroleum-based plastics.

Due to the advantages of high energy density and improved safety properties, Li metal batteries with gel polymer electrolyte (GPE) have drawn much attention in recent years. Herein, a novel gel thermoplastic polyurethane (TPU) electrolyte filled with ultrafine hydrophilic–lipophilic TiO2 nanoparticles was successfully prepared by using a phase separation technology. The gel electrolyte can protect the battery against the leakage of liquid electrolyte by means of its strong interaction with Li+ and solvents. This kind of GPE shows an ionic conductivity of 1.59 mS cm−1 and an electrochemical window of 4.3 V (vs. Li/Li+) at room temperature. Robust TiO2 nanoparticles embedded into TPU matrix can effectively block dendrite puncture and, besides, greatly improve the thermal stability of GPE. The cycling performance, rate capability and mechanical properties guarantee the reliability of the as-prepared GPE in Li-ion batteries.

Multienzymatic conversion of carbon dioxide (CO2) into chemicals has been extensively studied. However, regeneration and reuse of co-factor are still the main problems for the efficient conversion of CO2. In this study, a nanoscale multienzyme reactor was constructed by encapsulating simultaneously carbonic anhydrase (CA), formate dehydrogenase (FateDH), co-factor (NADH), and glutamate dehydrogenases (GDH) into ZIF-8. In the multienzyme reactors, cationic polyelectrolyte (polyethyleneimine, PEI) was doped in the ZIF-8 by dissolving it in the precursors of ZIF-8. Co-factor (NADH) was anchored in ZIF-8 by ion exchange between PEI (positive charge) and co-factor (negative charge), and regenerated through GDH embedded in the ZIF-8, thus keeping high activity of FateDH. Activity recovery of FateDH in the multienzyme reactors reached 50%. Furthermore, the dissolution of CO2 in the reaction solution was increased significantly by the combination of CA and ZIF-8. As a result, the nanoscale multienzyme reactor exhibited superior capacity for conversion of CO2 to formate. Compared with free multienzyme system, formate yield was increased 4.6-fold by using the nanoscale multienzyme reactor. Furthermore, the nanoscale multienzyme reactor still retained 50% of its original productivity after 8 cycles, indicating excellent reusability.

CdS nano-photocatalysts hold a great promise for the photocatalytic hydrogen evolution; however, their practical application is greatly hampered by poor activity and stability due to the recombination of the photogenerated charge carriers and photocorrosion phenomena. Herein, we report a novel 3-dimensional CdS@UiO-66 nanostructures obtained by a facile solvent-free approach; with a step-by-step procedure, the core/shell configuration provided a suitable unit in size to easily equip defect-rich MoS2 nanosheets. The UiO-66 Zr-MOFs used as a porous container to promote the dispersion of CdS nanoparticles, resulting to the increasement of active sites for photocatalytic reaction. The further enhanced photocatalytic activity for MoS2 hybrid CdS@UiO-66 originated from the manufactured defect on the exposed edges of MoS2 nanosheets, which was produced by adjusting the S/Mo ratio. UiO-66 did not only provide extensive migration routes over photogenerated electrons, more importantly, it created ample time and sites for accelerating consumption of the isolated photogenerated holes with sacrificial agent, resulting in alleviating photocorrosion reaction. The photocatalytic efficiency and photostability were simultaneously promoted. This work highlights the potential application of core/shell configuration in photocatalytic hydrogen evolution. CdS@UiO-66 type composite photocatalyst was obtained in the condition of solvent-free assembling at room temperature. The defect-rich MoS2 nanosheets were felicitously equipped on the core/shell configuration. The obtained defect MoS2 hybrid CdS@UiO-66 composite material exhibits a high and stable hydrogen production rate due to their synergistic effect.

Biological metal-organic frameworks (bioMOFs) are a new subclass of the MOF family. In comparison with traditional MOFs, the bioMOFs are made of multifunctional biologically related ligands (bio-ligand) and metal ions. The bio-ligands confer biological compatibility for traditional MOFs, thus providing many opportunities for a wide array of biological applications. This review highlights the recent advances in the synthesis of bioMOFs comprising multifunctional bio-ligands and metal ions. These bio-ligands include nucleobases, amino acids, peptides, proteins, cyclodextrin, saccharides, and other biomolecules. Furthermore, the potential bio-applications of bioMOFs in several fields such as biomedicine, biosensing and bioimaging, antimicrobial applications, biomimetic catalysis, chiral separation, and environmental protection are also demonstrated.

Li-dendrite resistant and high-performance separators are effective ways to solve the safety problem in advanced Li storage. Several intrinsic factors, including low thermal stability, low porosity and poor wettability, restrict the application of organic separators in safe Li storage. Inorganic porous membranes are promising candidates for commercial polyolefin-based separators due to their excellent thermal stability and good compatibility with organic electrolytes. In this study, we develop a flexible, Li-dendrite resistant and binder-free inorganic separator for safe Li storage based on ultralong Na2Ti3O7 nanobelts. The high thermal stability of Na2Ti3O7 nanobelts enables the separators to preserve their structural integrity up to 1000 °C. In addition, the as-prepared separators exhibit excellent flexibility, high porosity, and high cycling stability, which guarantee both the safety and high performance of the batteries.

Natural sepiolite mineral has been commonly used in the industry because of its unique structure and physical properties. In this paper, we fabricated sepiolite-based battery separators by simple and inexpensive electrospinning technology. The as-prepared sepiolite-based separators show high thermal stability and excellent electrochemical properties, making them a superior candidate for long-term operation under thermally stressful conditions. Our research indicates that sepiolite can be employed to improve the reliability and electrochemical performance of polymer-based separators.

This study focuses on the development of advanced water resistant bio-based composites with enhanced hygrothermal performance for building applications. The highly porous structure of hemp shiv is responsible for low thermal conductivity and allows the material to adapt to varying humidity conditions providing comfortable indoor environment. However, the pore network and the hydrophilic nature of hemp shiv affects the compatibility and durability of the material in presence of excess moisture conditions. In this work, novel hemp shiv composites were prepared in a starch based or silica based matrix and characterised for their hygroscopic, thermal and mechanical properties. The hemp shiv based composites were resistant to water yet permeable to vapour and showed excellent moisture buffering capacity when compared to conventional hemp-lime composites. The composites prepared were light weight with low thermal conductivity values of 0.051–0.058 W/mK and showed good mechanical performance. Hemp shiv composites with superior hygrothermal characteristics have immense potential as robust thermal insulation building materials.

Summary Solar-driven photochemical hydrogen evolution is a promising route to sustainable hydrogen fuel production. Large-scale preparation of highly active photocatalysts using elementally abundant and less-expensive materials is urgently required for widespread practical application. Here, we report a highly efficient and low-cost TiO2/MgTiO3/C heterostructure photocatalyst for photochemical water splitting, which was synthesized on gram scale via a facile mechanochemical method. The heterostructure and carbon sensitization offer excellent photoconversion efficiency as well as good photostability. Under irradiation of one AM 1.5G sunlight, the optimal TiO2/MgTiO3/C photocatalyst can show a great solar-driven hydrogen evolution rate (33.3 mmol·h−1·g−1), which is much higher than the best yields ever reported for MgTiO3-related photocatalysts or pure TiO2 (P-25). We hope this work will attract more attention to inspire further work by others for the development of low-cost, efficient, and robust photocatalysts for producing hydrogen in artificial photosynthetic systems., Graphical Abstract, Highlights • The synthetic process does not involve any organic solvents and hazardous by-products • The optimal sample shows a H2 evolution rate of 33.3 mmol·h−1·g−1 under one sunlight • The optimal sample keeps a H2 evolution rate of 1.46 mmol·h−1·g−1 under visible light • Uniform carbon layer was ingeniously deposited on the surface of photocatalysts, Catalysis; Energy Resources; Chemical Synthesis

The mechanical measurements of nanostructures are crucial to the development and processing of novel nanodevices. Herein, TiO2 nanotubes were synthesized from an electrospun method combined with subsequent heat-treatment. The elastic modulus and fracture strength of a single TiO2 nanotube were measured by atomic force microscopy (AFM). The effect of elastic modulus and dimensional size on the mechanical behaviors of the nanotubes was simulated by the finite element method (FEM).

Lipase-inorganic hybrid nanoflowers were prepared using Ca3(PO4)2 as the inorganic component and lipase from Aspergillus oryzae (A. oryzae) as the organic component. The influences of metal ions with different valence, various additives (surfactant), and synthesis conditions on the activity of the lipase hybrid nanoflowers were systematically investigated. Results revealed that the valence state of metal ions played an important role on the shape and activity of lipase hybrid nanoflowers. The synthesized lipase hybrid nanoflowers using bivalence metal ions (Ca2+, Mn2+, and Zn2+) as the inorganic components exhibited relative high activity. However, very low activities were observed in the lipase hybrid nanoflowers using univalent metal ions (Ag+) or trivalent metal ions (Al3+, Fe3+). More importantly, Ca2+ not only induced self-assemble of lipase hybrid nanoflowers, but also activated the enzyme activity by inducing conformational changes in lipase from A. oryzae. As a result, lipase/Ca3(PO4)2 hybrid nanoflowers (hNF-lipase) exhibited the high activity. The hNF-lipase displayed 9, 12, and 61 folds higher activity than lipase/Ag3PO4 hybrid nanoflowers, lipase/AlPO4 hybrid nanoflowers, and lipase/FePO4 nanoflowers, respectively. Compared with free lipase, the hNF-lipase displayed 172 % increase in activities by using 0.15 mM Tween-80 as an activity inducer (activated hNF-lipase). Furthermore, the hNF-lipase and activated hNF-lipase exhibited increased stability against high temperature and denaturant, and had good storage stability and reusability.

The natural hemp aggregates and their bio-composite panels which have been developed for sustainable construction with low thermal conductivity and high hygrothermal efficiency. The combination of the hemp aggregates with natural matrix materials results in exceptionally low thermal conductivity and high hygrothermal efficiency compared to conventional materials of construction as a result of their microporosity and breathability. In addition, the developed bio-based composites with nanotechnology improve resistance to liquid water and protect the hemp shiv from biodegradation without impacting the natural ability of the shiv to buffer moisture vapor.\ud \ud The chapter assesses the physical characteristics of hemp aggregates in terms of their density, microstructure and porosity. Hemp-concrete and novel Hemp-organic composite have been studied and compared. Measurements of the thermal conductivity of hemp-composite panels are described which confirm their highly insulating properties. Hygroscopic testing demonstrates their effectiveness in absorbing and releasing moisture. The thermal and hygroscopic performance of hemp-composite panels in test cells is reported together with their application in construction. The life cycle assessment of hempcrete and hemp organic composite were performed. This chapter is part of the output of the ISOBIO programme supported by the European Union Horizon 2020 program, within the ‘Materials for Building Envelopes’ call for Energy Efficient Buildings.

This work was designed to develop the chitosan-based melatonin layer-by-layer assembly (CMLLA) via the inclusion method. The structural characterizations and interaction present in CMLLA were investigated by the scanning electron microscope (SEM), X-ray diffraction (XRD) and Fourier Transform-Infrared spectroscopy (FTIR). The ratio of chitosan (CH) to carboxymethylcellulose (CMC) greatly influenced the mechanical properties, including the tensile strength, moisture content and color performance. Results showed that both antioxidant and antimicrobial properties of CMLLA were enhanced with the addition of melatonin (MLT). Furthermore, it was demonstrated that the CMLLA with 1.2 % (w/v) CH, 0.8 % (w/v) CMC and 50 mg/L MLT better contributed to the delay of chlorophyll degradation and the maintenance of shelf-life quality. Results from this study might open up new insights into the approaches of quality improvement of postharvest fresh products by incorporating the natural antioxidant compounds into natural polymers.

Electrochemically active SnO2 materials are prospective alternatives for graphite toward better flexible LIBs. However, significant volume changes and structural pulverization restrict the cycling stability and high capacity of SnO2. Here, we report a binder and conductive additive free core-shell N-doped carbon @SnO2 hybrid paper by a subtle coaxial-electrospinning method. Core-shell N-doped C@SnO2 fibers not only offer rapid ionic transport and sufficient buffer space for the volume expansion during the Li insertion and extraction reactions, but also enable high flexibility against both compression and bending deformation. As an anode for LIBs, the hybrid materials delivered a large initial capacity of 1799 mAhg−1 with capacity retention of 729 mAhg−1 after 100 cycles at a current rate of 390.5 mAg−1. More importantly, flexible N-doped C@SnO2 fabrics exhibit excellent electrochemical performance even after a rough treatment, suggesting a facile strategy for the fabrication of electrochemically stable electrodes for flexible LIBs.

ZnO/Ag2O photocatalysts with heterostructure were synthesized by a green and effective mechanochemical method. The preparation process was taken in solid state at room temperature with a short grinding time. The as-made products showed a high degree of crystallinity without post-calcination treatment. Such synthetic method does not involve any organic solvents and the reaction matrix can be recycled. The as-prepared ZnO/Ag2O samples show excellent photocatalytic activity and photostability for degradation of different organic dyes under visible light. The content of Ag2O plays an important role in the photocatalytic activity, which can be tuned by the precursor AgNO3. The photodegradation rate constant (k) of the optimal ZnO/Ag2O sample under visible light is nearly 0.1004 min−1 for methylene blue (MB), 0.063 min−1 for rhodamine B (RHB) and 0.07 min−1 for methyl orange (MO), which are much better than the pure ZnO (0.0075 min−1). The enhancement of the visible light photocatalytic activity could be attributed to the heterojunction interfaces induced by the match of crystal lattice and energy band between the Ag2O and ZnO. The Ag2O generates the excited-state electrons under visible light irradiation. The excited electrons on Ag2O could directly transfer to the conduction band (CB) of ZnO, making ZnO/Ag2O present remarkable visible light photocatalytic activity.

Temperature-dependent on/off PVP@TiO2 separator for Li-ion batteries (LIBs) has been fabricated by using a modified electrospinning method. The PVP@TiO2 separators show excellent wettability towards liquid electrolytes and high ionic conductivity due to its high porosity and outstanding capillarity. The battery with PVP@TiO2 separator will be suspended as the operation temperature reaches 60 °C, then revives after being brought back to room temperature. The PVP@TiO2 separator is thermally stable up to 180 °C without significant dimensional shrinkage. The structural integrity of the hybrid separator can be maintained even after being heat-treated at 500 °C. The use of this hybrid separator is one approach to improve the reliability and safety of the LIBs.

Natural assembly method was utilized to prepare a novel ternary Ag–SnS–TiO2 nanocomposite, in which TiO2 nanobelts were used as templates. The co-loading of Ag and SnS nanoparticles endows TiO2 nanobelts with enhanced photocatalytic capability, resulting from the broadened light absorption spectra and decreased band gaps. Comparing with raw TiO2 nanobelts and commercial Degussa P25, an improvement in photodegradation of simulated organic pollutants was successfully demonstrated due to the decreasing recombination of photogenerated electron–hole pairs. Our work presents a new strategy for the preparation of ternary TiO2-based photocatalysts in the practical application of wastewater treatment.

Uniform SnO2 fibers were prepared from the electrospinning method in this paper. The mechanical properties of a single SnO2 fiber were characterized by three-point bending experiments with atomic force microscopy. Finite element method was employed to simulate the shape of the SnO2 fiber during the bending process. The elastic modulus of SnO2 fibers increased with the calcined temperature. A high elastic modulus of 72.59 GPa was obtained with a diameter of 160 nm. The results indicate that atomic force microscopy tips penetrated the surfaces under maximum loading. The force-displacement curve from simulation is in accordance with the results from experiments by using AFM and theoretical calculation. The equivalent strain nephogram indicates that the maximal strain is about 0.0143 at the midpoint of the fiber.

The photocatalytic property of TiO2-based nanomaterials can be markedly enhanced by hybridizing conjugated materials at the surface. In this paper, we first utilized a silane coupling agent as carbon source and grafting reagent to prepare a graphite-like carbon coating on the surface of {001} crystal facets that were exposed on TiO2 nanobelts. The thickness of this carbon layer could be controlled to a thickness of a few molecules by adjusting the addition of silane. Due to the synergistic effects between the monolayer carbon coating (~1 nm) and the exposed {001} crystal facets, the as-prepared TiO2 nanobelts enhanced the photocatalytic activity by approximately 2.5 times that of pure TiO2 (Degussa, P–25), to photodegrade methylene blue under UV light. Additionally, the photodegradation of rhodamine B (RHB) was better (approximately 2.1 times) than that of P–25. Further, we discuss the proper mechanism of the enhanced performance, which is attributed to the faster transfer of photogenerated electrons by d-π interaction and the decreased possibility of recombination of e−/h+ pairs.

In this paper, Co