This study presents a sustainable and non-destructive recycling strategy for synthetic fibres, specifically polyethylene terephthalate (PET), polyamide 6 (PA6), polyamide 66 (PA66), and elastane (EL). Two deep eutectic solvents (DESs) were synthesised, enabling selective dissolution of EL without degrading the surrounding polymer matrices. The dissolved EL phase was subsequently recovered by centrifugation, demonstrating its potential for material reuse. Comprehensive characterisation confirmed that the process preserves fibre integrity. SEM imaging revealed no detectable changes in fibre morphology, while DSC and TGA analyses indicated that the thermal properties of both EL and synthetic polymers were preserved. ATR-FTIR spectroscopy verified the absence of measurable chemical modifications. Mechanical testing showed that solvent treatment did not compromise the tensile performance of PET, PA6, or PA66 fibres, confirming their suitability for fibre-to-fibre recycling. The recovered fibres were successfully re-extruded into continuous filaments, confirming their melt processability and enabling potential applications in textile yarns, technical fibres, nonwovens, and polymer components via melt-spinning or moulding. These results demonstrate that the proposed DES-based method offers a promising approach for the circular recycling of complex fibre blends and provides a viable pathway towards industrial implementation.

Cellulose nanopapers are attractive materials with outstanding mechanical and optical properties, yet their production is slow. The use of non-aqueous suspension media, in particular ethanol, for nanopaper production reduced filtration times by 73 %. Nanopapers prepared from ethanolic suspensions possessed higher porosities than those prepared from aqueous suspensions, reducing their transparency and tensile properties. Rewetting nanopapers prepared from ethanolic suspensions with water and subsequent drying yielded nanopapers with densities essentially the same as those prepared from aqueous suspensions, which in turn greatly increased mechanical properties and transparency. The strain to failure of rewetted and dried nanopapers prepared from ethanolic suspensions increased from 2.8 % to 7.5 %. The strain to failure of rewetted and dried nanopapers prepared from ethanolic suspensions was also greater than that of nanopapers prepared from aqueous suspensions (3.3 %) albeit at the expense of a 20 % decrease in tensile strength and modulus, which was shown to be attributable to a lower bonding contribution between fibrils in the network. The increased strain to failure results in significantly increased work of fracture. The rewetting and drying treatment also yielded nanopapers with high total luminous transmittance and haze.

This study investigates enzymatic hydrolysis of four novel polyesters (REPolymers) with different structures based on terephthalic acid, ethylene glycol, glutaric acid, and decanediol. These polyesters were synthesized from PET building blocks and bio-based monomers. A hydrolase from Rhizobacter sp. (Rhb), identified from a wastewater treatment sludge metagenome, was used to predict biodegradation and to assess enzymatic recycling potential of the REPolymers. Rhb shows homology to Ideonella sakaiensis PETase but exhibits superior thermostability and activity due to specific amino acids previously identified in PETase engineering. Using mass spectrometry and HPLC-DAD analysis, hydrolysis of REPolymers (5 - 34 kDa) was mechanistically studied. Mono-(2-hydroxyethyl) terephthalic acid (MHET) was the primary product, with longer PET oligomers and aliphatic dimers also detected, indicating endo-wise cleavage of aromatic and aliphatic ester bonds. Consistent degradation patterns showed dimer accumulation across different REPolymers. These findings illuminate how the polyester structure affects enzymatic hydrolysis, supporting the development of novel waste/bio-based polymers and recycling strategies.

Reconstruction of long-segment peripheral nerve gaps remains a clinical challenge, as neither autografts nor FDA-approved nerve conduits achieve satisfactory functional recovery. Conduits filled with native Trichonephila dragline silk show promise for nerve defects exceeding the critical length, but translating natural silk to clinical use has limitations, necessitating research into recombinant silk replica. The search for optimal silk templates is ongoing, with numerous spider species still unexplored. This study aims to compare the ability of four native silk fibers from phylogenetically diverse spider families to support nerve regeneration. The influence of fiber morphology, primary and secondary protein structures, surface charge, chemical composition, and mechanical properties on the initial cell attachment is studied. Results demonstrate that silk collected from Peucetia lucasi do not adequately support Schwann cell adhesion, which is caused by the lack of a lipid layer and the limited fiber wettability. This reduced wettability, governed by the ratio of hydrophilic and hydrophobic amino acids of silk, is particularly relevant when considering the deployment of uncoated artificial silk fibers for neural tissue engineering. This knowledge is crucial for paving the way toward full functional recovery after peripheral nerve injury via implanting advanced synthetic nerve guidance conduits enhanced with luminal silk alternatives.

Biochars (BC) are cost-effective and sustainable sorbents to clean up waters polluted with metal(loid)s. Understanding the influence of water chemistry is critical in identifying processes that limit metal(loid) removal. To address this, we investigated the removal of lead [Pb], arsenate [As(V)], and antimonite [Sb(III)] using BC in the presence of various solution constituents. A design of experiments approach was used to investigate sorption for each metal(loid)-BC setup (Pb with a straw BC, As(V) with charred wood-dolomite and Sb(III) with a steam-activated wood BC) with twenty-five different background solutions varying in calcium (Ca), natural organic matter (NOM), phosphorus (P), and iron [Fe(III)] content. Background solution composition affected removal of Pb (29 to 100%) more strongly than that of As(V) (37 to 92%) and Sb(III) (20 to 70%), with the selected BC at the metal(loid) concentrations studied. Pb removal was associated with Fe(III)-NOM-Ca organo-mineral phases for solutions containing Fe(III), NOM and Ca. As(V) sorption was enhanced by Ca due to cation-bridging and reducing the competition for sorption sites by NOM and P in high NOM and/or P containing solutions. Sb(III) sorption was hindered by oxidation to Sb(V) through redox active moieties in the BC in all solutions. Sb(III) removal decreased in the presence of high Fe(III), because Fe(III)/Fe(III)-NOM phases blocked accessibility to sorption sites in the highly porous BC, and/or due to enhanced oxidation of Sb(III) to the more mobile (but less toxic) Sb(V). Ideally, the design of BC sorbents for the removal of metal(loid)s from contaminated waters should a priori consider complex solution compositions.

The controlled cation substitution is an effective strategy for optimizing the density of states and enhancing the electrocatalytic activity of transition metal oxide catalysts for water splitting. However, achieving tailored mesoporosity while maintaining elemental homogeneity and phase purity remains a significant challenge, especially when aiming for complex multi-metal oxides. In this study, we utilized a one -step impregnation nanocasting method for synthesizing mesoporous Mn-, Fe-, and Ni-substituted cobalt spinel oxide (Mn0.1Fe0.1- Ni0.3Co2.5O4, MFNCO) and demonstrate the benefits of low-temperature calcination within a semi-sealed container at 150-200 degrees C. The comprehensive discussion of calcination temperature effects on porosity, particle size, surface chemistry and catalytic performance for the alkaline oxygen evolution reaction (OER) highlights the importance of humidity, which was modulated by a pre -drying step. The catalyst calcined at 170 degrees C exhibited the lowest overpotential (335 mV at 10 mA cm -2), highest current density (433 mA cm -2 at 1.7 V vs. RHE, reversible hydrogen electrode) and further displayed excellent stability over 22 h (at 10 mA cm -2). Furthermore, we successfully adapted this method to utilize cheap, commercially available silica gel as a hard template, yielding comparable OER performance. Our results represent a significant progress in the cost-efficient large-scale preparation of complex multi -metal oxides for catalytic applications.

Globally, vast amount of food-derived waste is generated including residues from fruit processing, which requires innovative strategies to avoid problematic disposal of useful resources. Orange peels contain a variety of valuable compounds such as limonene, enzymes, and carbohydrates that exhibit interesting properties for various applications. In this work, a biorefinery concept is presented to generate versatile bioproducts from orange peel waste. First, limonene and peroxidase enzymes were extracted from orange peels by solvent extraction and three phase partitioning, respectively. The remaining solids, containing mainly cellulose, were enzymatically hydrolyzed, and soluble monosaccharides converted into lactic acid (LA) by Weizmannia coagulans and the biopolyester polyhydroxybutyrate (P(3HB)) by Priestia megaterium. 8 g L-1 limonene and peroxidases with remarkable specific activity of 426 U mg(-1) were extracted. Utilization of the sugars in batch fermentations resulted in a LA concentration of 17 g L-1 as well as a P(3HB) content up to 43 % in cell dry weight without the need for further medium components. By combining these bioproducts, fully biobased polymer blend films of P(3HB) with PLA and limonene as plasticizer were successfully fabricated by thermoplastic processing, i.e., extrusion. In conclusion, the tested concept has shown very promising results and thereby emphasize the potential of the presented valorization strategies for orange peel waste.

Nanocellulose papers offer high tensile strength and modulus but suffer from drawbacks such as their brittle nature. We show that mercerisation of cellulose nanopapers in strong alkaline media for 2 min to 24 h results in the (partial) transformation of native cellulose I into the more ductile cellulose II allomorph. The strain to failure of mercerised nanopapers tripled compared to the original nanopapers while retaining their tensile strength in excess of 100 MPa at the expense of a slight drop in modulus resulting in a significant increase in toughness (total work of fracture). An additional advantage of mercerisation is a reduction in porosity of the nanopapers and increased transparency.

Oil palm trunk (OPT) is an inexpensive, abundantly available by-product of palm oil production which is typically not put to material use. Due to its comparably high cellulose content, OPT represents a suitable raw material for the preparation of cellulose nanofibrils (CNFs). Aiming for full utilization of the raw material and minimized energy demand, non-delignified and partially delignified (alkali-pretreated) OPT was subjected to mechanical fibrillation in the present study. As compared to CNFs from fully delignified OPT, the lignin-rich microfibrils obtained by this approach generally showed higher average fibril diameters, lower thermal stability as well as lower viscosity, and higher sedimentation rate in suspension. However, the combination of alkali-pretreatment and fibrillation by disc-grinding and subsequent high-pressure homogenization resulted in fibrils with properties similar to those of CNFs from fully delignified OPT. As proven by IR-spectroscopy, thermogravimetry and chemical composition analysis, alkali-treated OPT fibrils still contained substantial amounts of residual lignin which could, for instance, act as a natural coupling agent or binder in composite applications. Moreover, the facile delignification process applied herein requires far less chemicals and energy than conventional pulping and is thus beneficial from both the economic and ecological perspective.

Innovative approaches for recycling and upcycling of textile waste are required to sustainably treat the tremendous, discarded amounts. Due to their high specificity and mild reaction conditions, enzymes offer an environmentally friendly alternative for separation of blended materials. Glucose was recovered from cellulose (viscose) and polyamide blends and utilized as carbon source for biosynthesis of two biodegradable polymers. Polyhydroxybutyrate (PHB) was produced by Cupriavidus necator reaching an intracellular accumulation of 60 % (w/w) and 5.2 g/L of PHB from 20 g/L of glucose-rich hydrolysate. Bacterial cellulose (BC) was produced by Komagataeibacter sucrofermentans exhibiting equal properties to BC produced in standard media as confirmed by FTIR spectroscopy, SEM, and XRD. The recovered polyamide fibers were thermo-mechanically reprocessed and characterized by tensile testing showing comparable properties to virgin material. Thus, a combined bioconversion and mechanical reprocessing approach for textile waste is demonstrated allowing for recycling and valorization of each fraction of blended materials.

A large variety of substances, for instance heavy metal ions from different sources including mining, industry, and agricultural activities, pollute fresh water sources. Bio-based adsorbents, such as cellulose nanofibers (CNF), have recently been introduced in the process of treating water to remove hazardous pollutants primarily owing to their natural abundance, non-toxicity, and renewability. Surface modification of CNF, e.g. by catalytically oxidising the primary C6-OH groups of CNF selectively into carboxylic (COO−) groups with TEMPO, yields materials that are effective in adsorbing positively charged heavy metal ions, e.g. Cu ions. However, to utilise CNF in continuous processes beyond static, batch-wise adsorption, in particular on (pre-)industrial scale, they need to be immobilised on filter substrates in thin layers and an efficient manner. In this work, we report bio-adsorbent-based filters prepared by coating TEMPO-CNF on viscose filters using two different pilot-scale coating approaches, foam and cast coating. The performance of TEMPO-CNF filters was evaluated in terms of their water permeance as well as adsorption of metal ions including Cu(II) and Ca(II). By foam coating thin layers could be fabricated in a time efficient way facilitating high adsorption capacities (52 mg g−1), whilst by cast coating higher amounts of TEMPO-CNF could be deposited allowing for adsorbing higher absolute amounts (280 mg m−2) of heavy metal ions.

Carbons form critical components in biogas purification and energy storage systems and are used to modify polymer matrices. The environmental impact of producing carbons has driven research interest in biomass-derived carbons, although these have yield, processing, and resource competition limitations. Naturally formed fungal filaments are investigated, which are abundantly available as food- and biotechnology-industry by-products and wastes as cost-effective and sustainable templates for carbon networks. Pyrolyzed Agaricus bisporus and Pleurotus eryngii filament networks are mesoporous and microscale with a size regime close to carbon fibers. Their BET surface areas of ≈282 m2 g-1 and ≈60 m2 g-1, respectively, greatly exceed values associated with carbon fibers and non-activated pyrolyzed bacterial cellulose and approximately on par with values for carbon black and CNTs in addition to pyrolyzed pinewood, rice husk, corn stover or olive mill waste. They also exhibit greater specific capacitance than both non-activated and activated pyrolyzed bacterial cellulose in addition to YP-50F (coconut shell based) commercial carbons. The high surface area and specific capacitance of fungal carbon coupled with the potential to tune these properties through species- and growth-environment-associated differences in network and filament morphology and inclusion of inorganic material through biomineralization makes them potentially useful in creating supercapacitors.

Driven by climate change and human activity, Sargassum blooming rates have intensified, producing copious amount of the invasive, pelagic seaweed across the Caribbean and Latin America. Battery recycling and lead-smelter wastes have heavily polluted the environment and resulted in acute lead poisoning in children through widespread heavy metal contamination particular in East Trinidad. Our study details a comprehensive investigation into the use of Sargassum (S. natans), as a potential resource-circular feedstock for the synthesis of calcium alginate beads utilized in heavy metal adsorption, both in batch and column experiments. Here, ionic cross-linking of extracted sodium alginate with calcium chloride was utilized to create functional ion-exchange beads. Given the low quality of alginates extracted from Sargassum which produce poor morphological beads, composite beads in conjunction with graphene oxide and acrylamide were used to improve fabrication. Stand-alone calcium alginate beads exhibited superior Pb2+ adsorption, with a capacity of 213 mg g−1 at 20 °C and pH 3.5, surpassing composite and commercial resins. Additives like acrylamide and graphene oxide in composite alginate resins led to a 21–40

The interphases on the electrodes that form from electrolyte decomposition play a crucial role in the battery performance. However, with a thickness of only a few nanometres the formed passivation layers present a challenge to explore. In this work, we implemented a new approach by combining operando GC/MS gas analysis supported by surface sensitive XPS to investigate the electrolyte decomposition during SEI formation and deepen the understanding of the decomposition reactions of vinylene carbonate (VC) and fluoroethylene carbonate (FEC). Electrolyte degradation results in the formation of 29 different gas species. Adding additives resulted in (i) reduced gas formation and (ii) a clear shift from hydrocarbons to carbon oxides. Carbon dioxide was found to be indicative of the formation of poly-VC which was supported by findings from post-mortem XPS. An increased amount of fluorine was found in the interphases of cells using FEC as electrolyte additive. Acetaldehyde was identified as gaseous component to differentiate the decomposition of VC and FEC. For the decomposition of the base electrolyte components ethylene carbonate (EC) and diethyl carbonate (DEC), methane, ethane, ethene and butane were found to be indicative, and a scavenging effect of VC for alkoxides was confirmed by monitoring ethanol.

Efficient water treatment ideally combines ion exchange for the removal of hardness elements and toxic trace metals as well as ultrafiltration for the removal of particulate matter. Although promising for adsorption, many high‐surface‐area polymer materials cannot be easily processed into freestanding membranes or packed bed columns, due to poor solution processability and high back pressures, respectively. The preparation of hybrid membranes comprising sulfonated hypercrosslinked polymers entrapped in nanocellulose papers is described. The hybrid membranes are effective for simultaneous ultrafiltration and ion exchange. Increasing the polymer loading of the hybrid membrane produces synergy by increasing the permeance of the membranes while enhancing the ion adsorption capacity to values exceeding those of bulk hypercrosslinked polymers. The maximum ion adsorption capacity for copper is determined to be ≈100 mg g−1 outperforming that of pure polymer (71 mg g−1) and commercially available ion exchange resins. Competitive adsorption is tested in samples containing water hardness elements and trace toxic metal ions showing high ion‐exchange capacities. Even when fully loaded with water hardness elements, Ba2+ and Sr2+ are still removed from solution.

Liquid-like surfaces featuring slippery, omniphobic, covalently attached liquids (SOCALs) reduce unwanted adhesion by providing a molecularly smooth and slippery surface arising from the high mobility of the liquid chains. Such SOCALs are commonly prepared on hard substrates, such as glass, wafers, or metal oxides, despite the importance of nonpolar elastomeric substrates, such as polydimethylsiloxane (PDMS) in anti-fouling or nonstick applications. Compared to polar elastomers, hydrophobic PDMS elastomer activation and covalent functionalization are significantly more challenging, as PDMS tends to display fast hydrophobic recovery upon activation as well as superficial cracking. Through the extraction of excess PDMS oligomers and fine-tuning of plasma activation parameters, homogeneously functionalized PDMS with fluorinated polysiloxane brushes could be obtained while at the same time reducing crack formation. Polymer brush mobility was increased through the addition of a smaller molecular silane linker to exhibit enhanced dewetting properties and reduced substrate swelling compared to functionalizations featuring hydrocarbon functionalities. Linear polymer brushes were verified by thermogravimetric analysis. The optical properties of PDMS remained unaffected by the activation in high-frequency plasma but were impacted by low-frequency plasma. Drastic decreases in solid adhesion of not just complex contaminants but even ice could be shown in horizontal push tests, demonstrating the potential of SOCAL-functionalized PDMS surfaces for improved nonstick applications.

Multifunctional, biobased materials applicable within water treatment industry, produced through additive manufacturing technology.

Phase pure SnS and SnS2 were synthesized via the precipitation reaction and investigated as active anode materials for lithium-ion batteries. The crystal structure, morphology and chemical composition of the as-synthesized materials were determined by various physio-chemical techniques such as powder X-ray diffraction, scanning electron microscopy, transmission electron microscopy and X-ray photoelectron spectroscopy. The electrochemical properties of the SnS and SnS2 active anode materials were investigated by galvanostatic cycling with potential limitation, cyclic voltammetry, electrochemical impedance spectroscopy and electrochemical in-situ dilatometry. It was shown that the SnS2 electrodes exhibit superior cycling performance properties compared to the SnS electrodes. This is due to the higher amount of Li2S which is produced during the conversion reaction of SnS2 as well as to the intercalation of Li into the SnS2 crystal structure prior to conversion, which allows for a finer distribution of Li2S within the electroactive material.

Growing demand for animal products caused by a growing population and improved living-standards also yields large quantities of manure constituting an eminent problem. Herbivore manure can be utilized as fertilizer or for biogas production, which, however, disregards the full potential of manure as feedstock for lignocellulosics. Thus, an integrated process combining biogas production and isolation of natural fibres next to providing fertilizer precursors would constitute a major leap forward.

Magnesium-ion batteries represent promising environmentally sustainable energy-storage systems with higher energy densities than their lithium counterparts. In this work, the charge storage mechanisms of the olivine-related compound (Mg0.5Ni0.5)3(PO4)2 using Mg2+ and Li+ ions were investigated and compared for the first time when copper was chosen as the current collector. A comprehensive physicochemical and electrochemical characterization was performed on the pristine powder and electrodes at different states of charge. Although (Mg0.5Ni0.5)3(PO4)2 is electrochemically active, it undergoes irreversible conversion reactions in both Mg and Li chemistries. The conversion reactions proceed with an ionic exchange between structural Ni2+ and Mg2+ or Li+ cations, which results in the formation of sarcopside-Mg3(PO4)2, a Cu–Ni alloy and poorly crystalline Li3PO4, respectively. A capacity of 600 mA h g−1 was achieved with a Li metal counter electrode in the Li cell since the conversion reaction could go to completion. A capacity of 92 mA h g−1 was delivered in the Mg cell using an activated carbon counter electrode. These findings shed light on the fundamental mechanism of activity in olivine-related compounds, underlining the importance of performing systematic studies to unveil the complex interactions between both single-valent and multivalent ions with novel structures.