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Liquid crystal elastomers (LCEs) are a kind of polymer network that combines the entropic elasticity of polymer networks and the mesogenic unit by means of mild cross-linking. LCEs have been extensively investigated in various fields, including artificial muscles, actuators, and microrobots. However, LCEs are characterized by the poor mechanical properties of the light polymers themselves. In this study, we propose to prepare a carbon nanotube/liquid crystal elastomer (CNT/LCE) composite yarn by electrospinning technology and a two-step cross-linking strategy. The CNT/LCE composite yarn exhibits a reversible shrinkage ratio of nearly 70%, a tensile strength of 16.45 MPa, and a relatively sensitive response speed of ∼3 s, enabling a fast response by photothermal actuation. The research disclosed in this article may provide new insights for the development of artificial muscles and next-generation smart robots.

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This study attempted to fabricate heating fabrics using thin-film solar cells. A lightweight and flexible thin-film solar cell was used as the power supply, and fabric samples made of carbon fiber heating lines were used as heating elements. Single-factor experiments of three factors (solar cell voltage, heating time, and carbon fiber heating line arrangement) were conducted, and their influence on the heating effect was analysed. Orthogonal experiments and variance tests were used to determine the influence of the three factors and the optimal heating process. All influential factors were shown to be statistically significant. This kind of heating fabric can be used in warm clothing or for heated clothing.

The fatty acid ternary eutectics such as capric-lauric-myristic acid, capric-lauric-palmitic acid, capric-lauric-stearic acid, capric-myristic-palmitic acid, capric-myristic-stearic acid, and capric-palmitic-stearic acid and quaternary eutectics such as capric-lauric-myristic-palmitic acid, capric-lauric-myristic-stearic acid, capric-lauric-palmitic-stearic acid, capric-myristic-palmitic-stearic acid, and lauric-myristic-palmitic-stearic acid were selected as solid-liquid phase-change materials (PCMs). And then the innovative ternary eutectic/polystyrene (PS)/ternary eutectic and ternary eutectic/PS/quaternary eutectic form-stable phase-change composite fibrous membranes (PCCFMs) were directly prepared by the co-electrospinning method under the same spinning parameters. The as-prepared form-stable PCCFMs exhibited three-dimensional fibrous network structure with the average fiber diameter of about 410–780 nm according to the scanning electron microscopy images. The adhesion among nanofiber intersections was observed occasionally. The differential scanning calorimetry results showed that fatty acid eutectics have been successfully combined into the form-stable PCCFMs, and their melting peak temperatures mostly ranged from 15°C to 21°C with a temperature interval of 1°C. Moreover, the phase-change enthalpies reached about 40–61 kJ kg−1. It is concluded that these electrospun form-stable PCCFMs with appropriate phase-change temperatures could be considered as potential PCMs to be applied in thermo-regulating fibers and textiles.

Background: Silk sericin has a significant influence on the regenerated silk solution and silk-based materials property, while few reports were found to investigate this topic. Aim: The aim is to discuss the effect of silk sericin content on the electrospun silk nanofibrous membrane. Methods: Four degumming conditions (none degumming, boiling water degumming, 0.05 % Na2CO3 degumming, 0.5 % Na2CO3 degumming) were carried out for a systematic investigation in terms of (1) the silk sericin content after degumming; (2) the morphology of regenerated silk nanofibrous membrane was characterized by a Scanning Electron Microscope (SEM); and (3) structural properties of regenerated silk nanofibrous membrane by Fourier transform infrared (FTIR) spectroscopy, X-Ray Diffraction (XRD). Result and Conclusion: The results show that 0.5 % Na2CO3 degumming results in poor spinnability. The solutions derived from none degumming and boiling water degumming present high viscosity, leading to a hard silk nanofiber fabrication process. The silk nanofiber from the 0.05 % Na2CO3 degumming shows an easier fabrication process and better nanofiber morphology. These results will benefit the silk-based materials preparation, biomedical and separation application.

Background: Electrospun Cellulose Acetate (CA) nanofibrous membrane can be used in many areas such as biomedicine, water treatment. However, due to the strong hydrogen-bond interaction, the rare solvent can dissolve the CA and the resulting CA nanofibrous membranes always show bad morphology and poor performance. Aims: To research the effect of CaCl2-Formic acid (CaCl2-FA) solvent system on the morphology and structure of CA nanofibrous membrane. Methods: CA nanofibrous membrane was fabricated with a two-step dissolution method using the first step of CaCl2-FA solvent system followed by the second step of FA solvent solely. Subsequently, the CA nanofibrous membrane morphology and structure property were systematically investigated. Results and Conclusion: The results show that the CaCl2-FA can dissolve the CA efficiently. Additionally, the regenerated CA nanofibers are well-formed under all the CA concentrations with controlling fiber diameter ranging from 224.9 ± 38.6 nm to 367.8 ± 80.4 nm. The results suggest that this two-step dissolution method can be an effective and alternative approach to dissolve CA and regenerate CA nanofibrous membrane.

It is important to explore and develop multifunctional phase change composites with high latent-heat capacity and photothermal conversion capability. A novel ultralight and flexible carbon foam (CF)-based phase change composite was fabricated by encapsulating n-eicosane into a CF skeleton that had been precoated with titanium(III) oxide (Ti2O3) nanoparticles (NPs). Morphological structures, as well as the properties of leakage-proof, thermal energy storage, temperature regulation, and photothermal conversion, of the fabricated phase change composites were investigated. The results indicated that the flexible CF skeleton derived from melamine foam (MF) through stabilization in air followed by carbonization in nitrogen was highly porous, which ensured excellent mechanical support and large mass ratio of n-eicosane for the composites. The loading percentage of n-eicosane as high as 84% which acted as thermal storage unit guaranteed high latent-heat capacity and good temperature regulation property of the composite; the melting/crystallization temperatures and enthalpies of the corresponding composite was 36.4/33.7 °C and 200.1/200.6 kJ·kg–1, respectively. The CF skeleton modified with Ti2O3NPs endowed the fabricated phase change composites with enhanced leakage-proof property, photothermal conversion capability, superior thermal reliability, and temperature regulation ability. Therefore, the resultant phase change composites are believed to have promising and potential applications in solar thermal-energy storage, waste-heat recovery, and infrared stealth of military targets, and so forth.

High magnetic protective fabrics with rare earth Nd doped Fe3O4nanoparticles were fabricated via a grafting method. The structure, crystal form, and elemental composition of nanoparticles were investigated by transmission electron microscopy, energy dispersive X-ray, X-ray powder diffraction, and X-ray photoelectron spectroscopy. The obtained NdFe2O4nanoparticles show spherical shape with fine dispersion and reasonable element composition. However, they demonstrate fine superparamagnetic properties with a magnetic saturation value of 29.25 A m2/g and low coercivity of 1.902 mT through the vibrating sample magnetometry technique, which can be well developed in magnetic shielding protective applications. Then, the cotton fabrics with plain weave were finished by a proofing rapier loom as a carrier. The NdFe2O4nanoparticles underwent some appropriate surface modification and then were grafted onto the cotton fabrics by a bridge agent of N,N′-dissuccinimidyl carbonate. The morphology, structure, dispersion effect, and electromagnetic protective properties of the fabrics were observed through scanning electron microscopy, Fourier infrared spectroscopy, thermogravimetric analysis-differential scanning calorimetry (TG-DSC), and a vector network analyzer. The reliable fabrics with grafting reaction on the interface are expected to have potential applications in the field of electromagnetic protection and biomedicine fields.

A novel phenolic biosensor was prepared on the basis of a composite of polydopamine (PDA)-laccase (Lac)-nickel nanoparticle loaded carbon nanofibers (NiCNFs). First, NiCNFs were fabricated by a combination of electrospinning and a high temperature carbonization technique. Subsequently, the magnetic composite was obtained through one-pot Lac-catalyzed oxidation of dopamine (DA) in an aqueous suspension containing Lac, NiCNFs, and DA. Finally, a magnetic glass carbon electrode (MGCE) was employed to separate and immobilize the composite; the modified electrode was then denoted as PDA-Lac-NiCNFs/MGCE. Fourier transform infrared (FT-IR) spectra and cyclic voltammetry (CV) analyses revealed the NiCNFs had good biocompatibility for Lac immobilization and greatly facilitated the direct electron transfer between Lac and electrode surface. The immobilized Lac showed a pair of stable and well-defined redox peaks, and the electrochemical behavior of Lac was a surface-controlled process in pH 5.5 acetate buffer solution. The PDA-Lac-NiCNFs/MGCE for biosensing of catechol exhibited a sensitivity of 25 μA mM–1cm–2, a detection limit of 0.69 μM (S/N = 3), and a linear range from 1 μM to 9.1 mM, as well as good selectivity and stability. Meanwhile, this novel biosensor demonstrated its promising application in detecting catechol in real water samples.

Lauric acid (LA)/polyethylene terephthalate (PET) ultrafine composite fibres as form-stable phase change materials (PCM) were prepared successfully viaelectrospinning. The morphology, thermal energy storage properties, thermal stability and flammability properties of electrospun LA/PET composite fibres were characterized by scanning electron microscopy (SEM), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and microscale combustion calorimetry (MCC), respectively. It was found by SEM investigation that the average fibre diameter generally increased with increasing content of LA in the LA/PET composite fibres. The morphology of electrospun composite fibres changed from a cylindrical shape with a smooth surface (without LA) to a rough and non-uniform structure (with LA). The DSC measurements indicated that there was little change of the phase transition temperatures of the composite fibres, but there was a decrease of the heat enthalpies compared with the pure lauric acid. The TGA results showed that both the onset thermal degradation temperature and charred residue at 700 °C of composite fibres were lower than those of the pure PET fibres, due to the thermal instability of LA. The MCC tests showed that there were two peaks of heat release rate, which corresponded respectively to combustion of LA and PET in the electrospun composite fibres. It could be also found that the first peak increased and the second peak decreased with increasing LA content in composite fibres.

Fiber-supercapacitors (FSCs) hold great promise in smart wearable energy textiles due to the advantages of security, excellent deformability and unique integration structure. However, the integration of electroactive materials into economically viable textile fibers to produce FSCs with high energy density and mechanical flexibility remains a huge challenge. Herein, we fabricated NiCo2S4/PANI/CNTs hierarchical nanostructures on graphene polyamide blend fiber (GPAF) as effective cathodes for FSCs. The prepared composite fiber electrode exhibited a specific capacity of 1290 mF cm-2when the current density was 2 mA cm-2, which was benefitted from the delocalized conjugated system of PANI nanolayer and the unique nanostructure of NiCo2S4/PANI. Subsequently, the constructed asymmetrical fiber-supercapacitor (AFSC) delivered energy density up to 83.3 μWh cm-2when the power density was 420 μW cm-2. In addition, the AFSC also exhibited satisfactory cycling stability, maintaining 80.13% of the initial capacity after 5000 cycles. This work provides new ideas to promote the further development and practical applications of flexible fiber-supercapacitors and accelerate the development process of wearable energy textiles.

Hydrogels as a kind of soft material have received tremendous interests which are great promising candidate for wearable epidermal sensors to integrate prominent mechanical strength, high sensitivity and multiple detection mode. Herein, we proposed the synthesis strategy of a novel double network (DN) structure based on covalently crosslinked polyacrylic acid (PAA) network and ionic sodium alginate (SA) network to fabricate SAA (SA/PAA)/Al3+/MXene highly sensitive hydrogels for strain and pressure sensing. The strain sensors acquired a maximum gauge factor (GF) of 4.3 and fast response time of 210 ms, also displayed a good pressure sensitivity (0.075 kPa-1). Moreover, this epidermal sensor can monitor human motions by resistance or capacitance signals. We anticipated that this work can pave the way for designing wearable electric skins in the application of human motion monitoring and healthcare diagnosis.

The past decade has witnessed tremendous advances in the power conversion efficiency of organic photovoltaic cells. Concomitantly, the chemical structures of present high-efficiency photovoltaic polymers has become more complex, leading to tedious and harsh synthetic processes and high batch-to-batch variations. In comparison, polythiophenes have gained considerable traction and hold tremendous promise in terms of cost and scalability. In this review, we present state-of-the-art developments of polythiophene solar cells, with a focus on those made of P3HT and nonfullerene small molecule acceptors. First, the structural optimization of polythiophenes is briefly discussed. Then, we provide a concise discussion of two notable aspects (miscibility matching and crystallization control) for performance optimization and associated research highlights in the past five years. We also highlight the guidelines to ascertain the scientific challenges for polythiophene:nonfullerene solar cells. The development of new polythiophenes and their bulk-heterojunction blends will help stimulate advances in many kinds of cost-effective electronics.

A series of warm-toned long-lasting phosphor composite PMMA/RECC@SAOED were prepared by coating various concentrations of coumarin type red-emitting color converter (RECC) on the surface of yellowish-green emitting long-lasting phosphor SrAl2O4:Eu2+, Dy3+(SAOED) with the aid of PMMA encapsulation. The specific dynamic variation process of the phosphorescent color of PMMA/RECC@SAOED composites in darkness was systematically investigated. Results indicate that the perceived phosphorescent color of PMMA/RECC@SAOED undergoes an overall gradual shift toward blue in darkness after the removal of the excitation light, and the extent of this shift increases gradually with the increase of RECC. This work provides new perspectives in producing warm-toned emitting phosphors and investigating luminescent color.