Recently, the growing energy depletion and electromagnetic pollution have become two global issues that urgently need improvement. The development of bifunctional energy storage and electromagnetic interference shielding materials with good performances is quite a challenge. In this study, the surfaces of wasted polypropylene-based nonwoven fabrics (P-NWFs) are coated with silver paste via a facile screen-printing method to prepare conductive flexible substrates. Meanwhile, porous carbon nanofibers (PCNFs) are prepared through electrospinning technology and followed by the high-temperature sintering treatment. Significantly, conductive P-NWFs and PCNFs are composited together to form flexible fabric-based bifunctional materials. For supercapacitor application, the obtained electrode possesses a high specific capacitance of 343 F/g at 1 A/g. Besides, the device made from two electrodes shows a long cycling lifespan, capacitance retention is as high as similar to 99.68 %, after 10,000 cycles during charging/discharging process. For environment application, the obtained electromagnetic interference shielding material possesses a high shielding effectiveness of similar to 82.4 dB, where, >69 % of shielding is through absorption mechanism. Briefly, our research provides an innovative path for developing flexible fabric-based bifunctional composite materials for supercapacitor and electromagnetic interference shielding applications.

In recent years, the incidence of bone defects has been increasing year by year. Bone transplantation has become the most needed surgery after a blood transfusion and shows a rising trend. Three-dimensional-printed implants can be arbitrarily shaped according to the defects of tissues and organs to achieve perfect morphological repair, opening a new way for non-traumatic repair and functional reconstruction. In this paper, strontium-doped mineralized collagen was first prepared by an in vitro biomimetic mineralization method and then polylactic acid was homogeneously blended with the mineralized collagen to produce a comprehensive bone repair scaffold by a gas extrusion 3D printing method. Characterization through scanning electron microscopy, X-ray diffraction, and mechanical testing revealed that the strontium-functionalized composite scaffold exhibits an inorganic composition and nanostructure akin to those of human bone tissue. The scaffold possesses uniformly distributed and interconnected pores, with a compressive strength reaching 21.04 MPa. The strontium doping in the mineralized collagen improved the biocompatibility of the scaffold and inhibited the differentiation of osteoclasts to promote bone regeneration. This innovative composite scaffold holds significant promise in the field of bone tissue engineering, providing a forward-thinking solution for prospective bone injury repair.

Paper and fabric substrates are important foundational materials for the fabrication of flexible and printed electronic devices. This paper combines the research work undertaken for the project and, based on a review of the literature, comprehensively summarizes the roles, classifications, and processing techniques of paper-based and fabric materials in flexible and printed electronics. It compares the preparation techniques of such devices and introduces the achievements of chemical sintering and in-situ polymerization on paper-based electronics. Literature retrieval and analysis indicate that the development of paper-based/fabric electronic devices is essentially synchronized both domestically and internationally. It is believed that paper-based/fabric-based flexible electronic devices, including but not limited to circuits, electrodes, RFID tags, sensors, energy storage, and conversion devices, have their respective applications: paper-based devices are suitable for disposable, low-cost applications, while fabric-based devices are more suitable for wearable electronic products. Overall, in line with global carbon emissions control efforts, conductive and semiconductor materials suitable for fabric/paper-based flexible electronic products, including nano metals, conductive polymers, carbon materials, MXene, and other materials, will be prioritized for development. The related fabric/paper-based coating and printing industries will also rise in tandem with this trend.

A flexible electrode is a key component of electrothermal film for deicing. Here, silver electrodes were fabricated via screen printing 55 wt % silver content polypolyphenoxy (PKHH) resin-based conductive paste on the porous graphene-skinned quartz fiber fabric without a precoating layer. PKHH is favorable for excellent performance of electrodes, such as low resistivity (1.32 x 10-5 Omegacm), high adhesion (5B), and high tolerance for bending deformation. Fluorine-modified epoxy resin was introduced to electrically conductive adhesive (ECA) to improve the hydrophobicity and avoid the corrosion/oxidation of Ag during the deicing process, and ECA showed low resistivity (2.4 x 10-4 Omegacm) and stable mechanical connection (15 MPa). The deicing feasibility of film was demonstrated.

The rapid development of 3D printing technology and a series of polymer materials has made people’s daily life more convenient. 3D printing technology uses computer control to achieve fine, customized on-demand printing, which is not only resource-saving but also flexible and efficient. Silicone rubber is a polymeric silicone elastomer with a Si-O-Si bond in the main chain and an organic group in the side chain, which has high elasticity, high and low temperature resistance, aging resistance and excellent biocompatibility, and has been widely used in various fields such as biomedical, aerospace, mechanical engineering, and optoelectronic materials. Combining 3D printing technology with silicone rubber materials can not only broaden the scope of 3D printing technology, but also make better use of silicone rubber materials to provide convenience in daily life. This study mainly discusses the current development status of 3D printing silicone rubber materials and the future development direction.

导电聚合物(CPs)具有成本低、合成简单的优点.CPs常与金属、碳基材料或其他功能材料复合,制备性能多样的CPs功能油墨.CPs功能油墨通过各种印刷工艺,被沉积在基材上以形成功能层或电极.该类功能油墨能够应用于传感、储能、生物医学等多个领域,为印刷电子的未来发展提供理想平台.本文综述了近年来CPs功能油墨的研究进展和在印刷电子领域的应用,并提出了对当前研究和技术发展前景的看法和期望.

The use of AgNO3-polyvinyl alcohol (PVA) ink and oxygen plasma to form conductive coatings on plastic substrates was studied. It was found that oxygen plasma can decompose silver complexes to form metallic silver without high-temperature heating. The AgNO3-PVA ratio and plasma parameters (time, power) were optimized to obtain uniform conductive coatings. The morphology and electrical characteristics of the coatings were evaluated. Composite coatings with high reflectivity and good adhesion were prepared with a resistivity of 1.66 × 10−6 Ω·m using MOD inks with a silver ion mass fraction of 5%, after 300 W plasma treatment of the PET substrate for 2 min (the chamber temperature was 37.3 °C). These results demonstrate the potential feasibility of silver MOD inks and oxygen plasma treatment for the production of silver connectors, electromagnetic shielding films, and antimicrobial coatings on low-cost plastic substrates.

As a key material for printed electronics, conductive inks have received extensive attention. Conductive polymer polyaniline (PANI) as a conductive filler has the advantages of easy synthesis, low cost, high conductivity and good environmental stability, which provides a new way for the application and development of conductive inks. In order to fully grasp the progress of PANI conductive ink and its application, this paper comprehensively analyzes the research progress, application and preparation process of PANI conductive ink based on the literature and research work of conductive polymer ink in recent years. It is pointed out that the main development direction of PANI conductive ink is to compound PANI with other functional materials (such as metals and carbon materials) to form a stable, efficient, low-cost and environmentally friendly composite conductive ink, and the application prospect of PANI conductive ink is proposed.

A polymer network with a memory effect based on a polymer-stabilized narrow-bandwidth cholesteric liquid crystal (CLC) was prepared using the washing-out/refill method. The effects of different polymerization conditions on the reflection properties of CLC films were investigated. Meanwhile, the selective reflection property and narrow-bandwidth reflection memory effect of the polymer network were proved, and the response mechanism was provided. Furthermore, different materials from liquid crystals, with an anisotropic refractive index, to toluene, with an isotropic refractive index, were refilled to polymer scaffolds with helical structures, which originated from the periodic arrangement of CLCs. It was confirmed that the reflection bandwidth of these films can be dramatically narrowed by the reduced birefringence (Δn) of the refilled materials. The narrowest bandwidth of 22.5 nm refilling toluene with an isotropic refractive index (Δn = 0) was obtained. These results may provide a novel idea for flexible reflective displays, color filters, printing, and colored cladding of a variety of objects.

Using fluorescein and thiophene hydrazine, a new multi-ion detection fluorescent probe called YS was created in this study. It can detect Al3+ and Cu2+ by the fluorescence on and off phenomena, respectively. The binding ratio of YS to both Al3+ and Cu2+ was calculated by Job's plot as 1:1, and the binding constants of YS to Al3+ and Cu2+ were calculated by Benesi-Hildebrand method as 1.38×105 M-1 and 2.09×104 M-1, respectively. Finally, by examining the data from the fluorescence gradient concentration test, It can be observed that the fluorescence probe YS has high sensitivity and selectivity for both Al3+and Cu2+, with a minimum detection limit of at 12.65nM and 4.732nM, both of which are lower than the WHO standards for the corresponding ions in drinking water. The convenience detection test demonstrated that YS can achieve in situ rapid detection of Al3+ and the results are easy to observe and distinguish.

Flexible sensors play an important role in collecting stimuli information and sending them to a central processing unit or cloud for analysis and decision‐making. As much information is needed to be collected, the fabrication of multiparameter flexible sensors is becoming increasingly urgent. To this end, conducting polymer‐based composites have been proven as promising materials for developing pressure‐temperature dual‐parameter sensors. However, fabrication of ideal dual‐parameter sensors with fully decoupled pressure‐temperature readings, good sensitivity, and a simple preparation process remain challenges. Here, a strategy of fabricating a pressure‐temperature dual‐parameter sensor based on conformal printing of conducting polymer poly(3,4‐ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) on the surface of microstructured polydimethylsiloxane (PDMS) substrate is demonstrated. It is found that secondary doped PEDOT:PSS provides temperature‐independent conductivity. Combined with the sea‐island microstructured PDMS substrate, a screen‐printed flexible sensor demonstrates fully decoupled pressure‐temperature reading ability, competitive sensitivity, and good stability. The excellent sensing properties of the devices, with a maximum pressure sensitivity of 134.25 kPa −1 and linear response region over 300 kPa as well as highly sensitive temperature sensing for finger touch, together with their unique advantages of low‐cost and large‐area fabrication, make the printed flexible dual‐parameter sensors promising applications in electric‐skin (e‐skin), human‐machine interaction, and robotics.

Nano silver conductive inks are currently the most widely used metallic conductive inks. Due to the poor heat resistance of flexible substrates such as fabrics, paper, and plastics, the low-temperature sintering（＜200℃） and even room temperature sintering of printed circuits has become a hot topic in research. Combined with the literature report and the work of our group, nanosilver and its preparation technology were discussed, several low-temperature sintering techniques were analyzed and compared, especially the chemical sintering. Compared with other sintering technologies, chemical sintering has a wide range of applications, simple operation, high efficiency and energy saving. Nano silver printed circuits with a resistivity of 1.21×10 -7 Ω·m can be obtained by the ligand switching method. The optical sintering time is short and the efficiency is high, but it is expensive. Electrosintering is highly selective and subject to electrothermal conversion. Microwave sintering has high selectivity, but takes a long time, and the sintering effect is closely related to the size of the nanoparticles. Plasma sintering requires vacuum conditions, complex equipment, and long sintering times. In general, the low-temperature sintering method of the specific printed circuit should be selected by comprehensively considering the factors such as conductive ink, printed circuit and substrate.

In this paper, phenolphthalein and thiophene hydrazide are used as raw materials to design and synthe-size a fluorescent probe (FS) that can selectively detect trace amounts of Al3 + ions in dimethyl sulfoxide and ethanol. After FS is combining with Al3 + ions, the photo induced electron transfer (PET) is inhibiting, so it emits strong blue fluorescence (453 nm) to realize the specific detection of Al3 + ions. Tested by Job's plot and Benesi-Hildebrand method, the binding ratio and binding constant of FS and Al3 + ion are 2:1 and 5.6 x 10 5 M -1, respectively. As shown by the fluorescence gradient concentration testing, the min-imum detection limits of FS in DMSO and ethanol were 2.75 x 10 -8 M and 1.8 x 10 -8 M, respectively, both of which were lower than the WHO standard for Al3 + ions in drinking water (7.41 mu M). FS fluores-cent probes can be prepared as detection solvents and test strips for a wide range of applications in the detection of trace Al3 + ions.(c) 2022 Elsevier B.V. All rights reserved.

Herein, a simple approach for the fabrication of luminous self-assembled fibers based on halogen-bonded azopyridine complexes and oleic acid-modified quantum dots (QDs) is reported. The QDs uniformly align on the edge of the self-assembled fibers through the formation of van der Waals force between the alkyl chain of oleic acid on the QD surface and the alkyl chain of the halogen-bonded complexes, 15Br or 15I. Furthermore, the intermolecular interaction mechanism was elucidated by using Fourier-transform infrared spectroscopy (FTIR), Raman spectroscopy, and density functional theory (DFT) calculations. This approach results in retention of the fluorescence properties of the QDs in the fibers. In addition, the bromine-bonded fibers can be assembled into tailored directional fibers upon evaporation of the solvent (tetrahydrofuran) when using capillaries via the capillary force. Interestingly, the mesogenic properties of the halogen-bonded complexes are preserved in the easily prepared halogen-bonded fluorescent fibers; this provides new insight into the design of functional self-assembly materials.

Thiophene polymers have attracted extensive attention due to their good solubility, conductivity and stability, as well as the changeable properties of α and β positions where various groups can be connected. In this paper, poly (5,5’-dibromo-2,2’-bithiophene) conductive ink was prepareed through UV polymerization, and the conductivity was studied by adjusting the dopant content. The results indicated that when I2 is 75 wt%, PSS is 15 wt% and MXene is 10 wt%, the minimum resistance of polythiophene ink was obtained.

Poly L-lactic acid (PLLA) is a non-toxic, biocompatible degradable polymer material with excellent mechanical properties after moulding. However, it faces challenges in the use of biomedical materials because of its intolerance to bacteria. Here, we use an easy-to-operate method to prepare a composite multilayer membrane: PLLA membrane was used as substrates to assemble positively charged chitosan and negatively charged Ag@MXene on the surface using the layer-by-layer (LBL) method. The assembly process was detected by fluorescein isothiocyanate-labelled chitosan and the thickness of the coating multilayer was also detected as 210.0 ± 12.1 nm for P-M membrane and 460.5 ± 26.5 nm for P-Ag@M membrane. The surface self-assembled multilayers exhibited 91.27% and 96.11% growth inhibition ratio againstEscherichia coliandStaphylococcus aureusstrains under 808 nm near-infrared laser radiation with a synergistic photothermal antibacterial effect. Furthermore, best biocompatibility of P-M and P-Ag@M membranes compare to PLLA membrane motivated us to further explore its application in biomedical materials.

Stretchable conductor is the key component of stretchable electronic devices which has become an important development direction of flexible electronic. Patterned stretchable conductor is one of the key technologies for successfully manufacturing stretchable electronic devices. In order to acquire stretchable conductor with good conductivity and stable mechanical stretchability, stretchable conductive ink based on liquid metal nanoparticles (LMNPs) and silver flakes was developed and printed on the modified PDMS substrate by screen printing technology. Liquid metal recovered the fluidity and connected with the silver flakes under pressure after drying. So the fluidity and conductivity of the liquid metal can be used to achieve the preparation of stretchable conductor and overcome the trade-off between conductivity and stretchability. The initial resistance of prepared stretchable conductor is 2 Ω, and the resistance change rate is 0.65 when the tensile strain is 110

柔性压力传感器具有易共形、高灵敏、快响应等特点,是发展物联网、可穿戴电子、触觉人工智能等领域的关键核心器件.通过敏感功能材料开发、功能层微结构设计、微纳制造方法优化等策略,可提升柔性压力传感器的综合性能,扩张其应用场景.其中,功能层微结构的创新设计被普遍认为是增强柔性传感器性能最有效的手段之一.本文综述了近年来基于微结构化的柔性压力传感器的最新研究进展,围绕微结构对于柔性压力传感器性能增强的机制、微结构的设计与实现方法以及微结构化柔性压力传感器在人机交互、医疗健康等领域的应用等方面进行详细阐述,并在此基础上对其未来发展方向进行展望.

A simple and novel method for the deposition of polypyrrole (PPy) and cellulose nanocrystal (CNC) composites on different fiber substrates by reactive ink-jet printing was proposed. PPy/CNCs composites were successfully prepared, and the surface resistance of conductive layer deposited on different fiber substrates is the least when the monomer concentration is 0.6 M. PPy/CNCs were deposited on polyethylene terephthalate (PET) to form a conductive layer by adding polyvinyl alcohol (PVA), and the optimum sintering temperature is 100 °C (monomer/PVA ratio 4.0, conductivity 0.769 S cm−1). The PPy/CNCs conductive layer deposited on the paper has the lowest surface resistance and the best adhesion, and the surface resistance of PPy/CNCs conductive layer decreases first and then increases with the increase of sulfonate concentration. Moreover, the volume of anion in sulfonate will affect the arrangement and aggregation of PPy molecular chain in composite materials. Appropriate sulfonate doping can improve the conductivity and stability of conductive paper, and the maximum conductivity is 0.813 S cm−1. Three devices based on PPy/CNCs conductive paper were proposed and fabricated. Therefore, this ink-jet printing provides a new method for the preparation of conductive materials, sensors, energy storage and electromagnetic shielding, etc.

Printed electronics is an emerging technology that applies traditional printing or coating processes to the manufacture of electronic devices and products. In order to find a low-cost, high-performance, environmentally-friendly flexible substrate suitable for electronic devices, the printability between four kinds of inkjet photo papers and nano-silver ink was investigated. First, different surface morphologies of the inkjet photo papers were measured by a confocal laser scanning microscopy. Then, a pen and a gravure printer were used to test the printability between photo papers and nano-silver ink. It was found that the conductive track and pattern was influenced by the surface morphology of the photo papers. Furthermore, a four-probe test showed that the conductivity of the ink layers on the four photo papers was almost at the same level. Furthermore, a tearing test with 3 M tapes showed that the silk photo paper had the best tearing resistance. In general, silk photo paper has the best overall performance. This research could be beneficial for the development of flexible electronic devices which are low-cost, mass manufacture suitable and environment friendly.