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Interfacial solar‐vapor generation (ISVG) is an emerging technology for water purification. However, high cost, low evaporation rate, clogging issues, and limited solar utilization under natural condictions greatly hinder its practical application. Herein, inspired by the aligned microstructure of dragonfly wings, a 3D microarray structure composed of vertically aligned hierarchical and hydrophilic carbon fibers (CFs) is constructed using a scalable fiber manufacturing technology. The microarray structure of the high‐thermal‐conductivity CFs with nanocapillaries contributes to the fast mass (steam and salt ions) and heat transfer as well as high omnidirectional light absorption. More importantly, due to the strong multiscale capillary effect, the formed 3D water evaporation surface containing abundant micro‐meniscuses and nanoscale thin water layers in the CFs arrays effectively reduces the evaporation enthalpy and creates more water/air interfaces, leading to the significant increasing evaporation rate. As a result, a high evaporation rate of 2.21 kg m−2 h−1 under one‐sun irradiation can be achieved. Moreover, the off‐grid water treatment device assembled with multiple 3D CFs‐based customized spherical evaporators can obtain a high pure water collection of 10.71 kg m−2 per day without salt accumulation under real environmental conditions. This work demonstrates a high‐efficiency, cost‐effective, and scalable strategy for high‐performance ISVG. [ABSTRACT FROM AUTHOR]

Aiming at the problem of the limited application of bio-based polyethylene furandicarboxylate (PEF) in the field of textile and chemical fiber due to its small molecular weight and high brittleness, PEF was synthesized using various catalysts and polymerization condition. A zinc acetate-Ti(OBu)4 combined catalyst was chosen to fabricate the PEF suited for spinning, whose mean molecular weight (Mn) approached to 30 000 g/mol and the polymer dispersity index (PDI) was less than 3. Fourier transform infrared spectrometer (FTIR) and 1H-NMR were used to characterize the morphology and structure of PEF. Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) were conducted to characterize the thermal properties of the polyester. The PEF fibers were prepared through the two-step method UDY-DTY (undrawn yarn-drawn twist yarn) and the effect of drawing ratio on the mechanical properties of fibers was studied. The results show that the glass transition temperature of PEF is 90-92 °C, the melting point of PEF is 210-213 °C, and the initial thermal decomposition temperature of PEF is higher than 370 °C,indicating that PEF has good thermal stability. The highest breaking strength of PEF fibers is 2.17 cN/dtex, which can basically meet the application in textile field. [ABSTRACT FROM AUTHOR]

Terephthalic acid and ethylene glycol were used to prepare poly(ethylene terephthalate)-co-amide salts with adipate pentamethylenediamine (AP salts) as the modified monomer, improving the hygroscopicity and softness of poly(ethylene terephthalate) fibers. One of the facets of concern is that the yellowing index of poly(ethylene terephthalate)-co-amide salts increases from 3.8 to 13.8 than poly(ethylene terephthalate) and increases from 2.9 to 11.7 for fibers, limiting its acceptance in textile applications. The convention underpinning the yellowing originated from thermal oxidation and Schiff base reaction in the blend of polyester/polyamide, generating yellowing substances with conjugated imine structure. However, in this paper, an unconventional yellowing mechanism was discovered, attributed to the reaction of AP salts and acetaldehyde (a by-product of poly(ethylene terephthalate)). The structure of yellowing substances was characterized and confirmed the role of conjugated diketoamine (O=C–CH2–CONH–) and conjugated enamines (O=C–C=C–NH–). It is difficult for fiber applications to overcome the yellowing issue. Nevertheless, an inhibiting method for the yellowing phenomenon was provided, end-capping technology, by a clearer understanding of the yellowing processes. Thus, poly(ethylene terephthalate)/APA was prepared with the end-capping product carboxyl-terminated diamide (APA) as the modified monomer, which was synthesized by the reaction of AP salts and adipic acid. The yellowing index decreased from 13.8 to 8.5 than poly(ethylene terephthalate)-co-amide salts and decreased from 11.7 to 6.9 for fibers. This significantly improves the yellowing problem and provides technical support for colorless copolymer fibers. [ABSTRACT FROM AUTHOR]