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Background : Employing citric acid/dimethyl formamide (CA/DMF), two distinct types of carbon quantum dots (CQDs), tree-shaped/fingerprinted (TF-CQDs) and fullerene-like (F) were synthesized from both cellulose and carboxymethyl cellulose (CMC). Methods : Fluorescence microscopy revealed different emission colors: blue for TF-CQDs and green for F, highlighting the structural influence on light properties. Transmission electron microscopy (TEM) confirmed the intricate fingerprinted and tree-like morphology of TF-CQDs and the spherical nature of F derived from CMC. The adsorption behavior and kinetics of Cr(vi) removal from water by TF-CQDs and F were evaluated. Significant findings : Both samples demonstrated rapid Cr(vi) uptake; TF-CQDs reached equilibrium within 120 minutes compared to 240 minutes for F. Subsequent leaching led to decreased adsorption after these initial periods. Kinetic analysis revealed a first-order model for TF-CQDs, implying physical adsorption dominance. Conversely, F exhibited a better fit to pseudo-first and second-order models, suggesting combined chemical and physical mechanisms., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

This work deals with the fabrication of lignin containing cellulose nanofiber (LCNF)/Ag 2 Se films for thermoelectric applications. Ag 2 Se nanoparticles were synthesized within the LCNF network through in situ methods, employing Na 2 SeO 3 and AgNO 3 along with microwave energy treatment. LCNF/Ag 2 Se films fabricated with two LCNF : Ag 2 Se weight percent ratios ( i.e. , 50 : 50 and 30 : 70) were used to construct a flexible thermoelectric module. The obtained Ag 2 Se nanoparticles displayed a uniform size distribution in the LCNF network with smaller dimensions from the microwave energy treated group. The microstructure of LCNF/Ag 2 Se films was improved by hot-pressing, leading to enhanced film density thermoelectric properties. At a differential temperature of 50 K, films with 50% and 70% of Ag 2 Se exhibited output voltages of 18 and 21 mV; and Seebeck coefficients of -60 and -70 μV K -1 at 350 K, respectively. When microwave energy was applied, the films at 50% and 70% Ag 2 Se showed highest output voltages of 19 and 33 mV, respectively, and Seebeck coefficients of -63.3 and -110 μV K -1 at 350 K. The low-cost fabrication process associated with this module opens a pathway for applications such as energy harvesting., Competing Interests: No conflicts require declaration., (This journal is © The Royal Society of Chemistry.)

This study promotes the use of nanobiochar (NBC) as an environmentally friendly substitute to conventional fillers to improve various properties of biopolymers such as their mechanical strength, thermal stability and crystallization properties. TGA analysis showed a slight increase in onset thermal degradation temperature of the composites by up to 5 °C with the addition of 4 wt% NBC. Non-isothermal DSC analysis determined that the addition of NBC into PHBHHx increases the crystallization temperature and degree of crystallinity of PHBHHx while isothermal DSC analysis demonstrated higher crystallization rate in PHBHHx/NBC composited by up to 54%. PHBHHx incorporated with NBC also exhibited superior tensile strength and modulus versus neat PHBHHx. Increase in mechanical strength was further proven via DMA where PHBHHx/NBC composites maintained higher storage modulus at higher temperatures when compared to neat PHBHHx. PHBHHx/NBC also exhibited no cytotoxicity effect against HaCat cells. This study demonstrates the ability of biochar to act as both nucleating agents and reinforcing agents in biodegradable polymers such as PHBHHx, which could be suitable for packaging application., Competing Interests: There are no conflicts of interest to declare., (This journal is © The Royal Society of Chemistry.)

A W/ZSM-5 zeolite was successfully prepared by incorporating tungsten transition metal into a zeolite structure using a conventional impregnation method. The as-obtained W/ZSM-5 zeolite was characterized using several characterization techniques such as XRD, IR and SEM-EDS. The catalyst was then applied to a cascade, single-batch reaction to synthesize bio-polyol from sunflower oils using H 2 O 2 in isopropanol solvent. The obtained results indicated that the W/ZSM-5 zeolite had high catalytic efficiency in the epoxidation of the double bond of vegetable oil and the epoxy ring opening reaction to form bio-polyol. The effect of different reaction conditions on bio-polyol synthesis, such as the dosage of the catalyst and reaction time, were investigated. Bio-polyol was obtained from sunflower oil with a hydroxyl number of 160 mg KOH per g and functionality of 2.9 OH groups per mol. The as-synthesized sunflower oil-based polyol was used to replace fossil-based polyol in the fabrication of a bio-polyurethane-based composite with high oil uptake capacity. The oil adsorption capacity of the porous polyurethane-corn stalk composite was relatively high, up to 15.07 g g -1 . In comparison with neat polyurethane and lignocellulosic materials, the new porous bio-composite had higher oil uptake capacity., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Environment-friendly and biodegradable packaging materials have attracted widespread attention. Development of green solutions to extend the fruit shelf life and address fruit preservation thus has a far-reaching impact. In this study, high-barrier white cardboard (WC) was prepared by a facile coating method. Compared with the WC substrate, the WVP value of the polyvinylidene chloride (PVDC) emulsion-coated WC (3.46 × 10 -11 g m m -2 s -1 kPa -1 ) decreased 73.8% and the OP value (14.8 cm 3 m -2 day -1 ·Pa -1 ) decreased 61.9%. In addition, the mechanical properties of the PVDC emulsion-coated WC increased significantly. The weight loss rate and decay rate of the stored fruits packaged with PVDC emulsion-coated WC decreased by about 5%. The high barrier PVDC emulsion-coated WC with excellent mechanical properties, good barrier effect, and preservation function was successfully prepared. Benefitting from these investigated characteristics, the obtained coated WC can be used to package fruits to reduce water loss and delay ripening, and thus extend their shelf life, exhibiting a favorable effect on blueberry and grape storage. Overall, the fabricated eco-friendly coated white cardboard has shown great potential for biodegradable packaging applications. We believe the current work presents an approach to address perishable fruit preservation and provide a supplement alternative., Competing Interests: The authors declare no conflict of interest., (This journal is © The Royal Society of Chemistry.)

Paper-based materials with precisely designed wettabilities show great potential for fluid transport control, separation, and sensing. To tune the wettability of paper, paper sheets are usually modified after the paper manufacturing process. This limits the complexity of the local wettability design. We combined the wettability design of the individual fibres with subsequent paper sheet fabrication through either fibre deposition or fibre printing. Using silica-based cellulose fibre functionalization, the wettability of the paper sheets, containing only one specific fibre type, could be gradually tuned from highly hydrophilic to highly hydrophobic, resulting in water exclusion. The development of a silica-functionalized fibre library containing mesoporous or dense silica coatings, as well as silica with varying precursor compositions, further enabled the variation of the paper wettability and fluid flow. By combining this fibre library with the paper fabrication process by (i) fibre deposition or (ii) fibre printing, the paper wettability architecture and thus the local fibre composition were adjusted without any further processing steps. This enabled the fabrication of papers with wettability integration, such as a wettability pattern or a Janus paper design, containing wettability gradients along the paper sheet cross section. This asymmetric wettability along all three spatial dimensions enabled side-selective oil-water separation., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)