Composite Films Research Articles

Multifunctional composite film of curcumin Pickering emulsion stabilized by lignocellulose nanofibrils isolated from bamboo shoot shells for monitoring shrimp freshness

Concerns about food safety and environmental impact from chemical surfactants have prompted interest in natural lignocellulosic materials as alternatives. In this study, we combined hydrated deep eutectic solvent (DES) pretreatment with ultrasound treatment to prepare lignocellulosic nanofibrils (LCNF) from bamboo shoot shells with appropriate surface properties for stabilizing Pickering emulsions. The pretreatment intensity effectively modulated the surface characteristics of LCNF, achieving desirable wettability through lignin retention and in-situ esterification. The resulting LCNF/curcumin Pickering emulsion (CPE) demonstrated curcumin protection and pH-responsive color changes, while the ensuing CPE/PVA composite film exhibited ultraviolet shielding, mechanical strength, oxygen barrier, and antioxidant properties. Furthermore, the CPE/PVA film showed promise as a real-time indicator for monitoring shrimp freshness, maintaining sensitivity to spoilage even after six months of storage. These findings advance the advancement of green LCNF technologies, providing eco-friendly solutions for valorizing bamboo shoot shells and enhancing the application of LCNF in Pickering emulsions.

Study of Interlaminar Fracture Toughness and Flexural Properties of Carbon Fibre Composites Reinforced with Polyethersulfone/Graphene Oxide Films

Unidirectional carbon fibre reinforced plastic (CFRP) composites were prepared by inserting polyethersulfone (PES) films or polyethersulfone/graphene oxide (GO) films into the composites and used to improve the interlaminar fracture toughness as well as the flexural properties. The effect of low-temperature cycling (35, 70, 105, and 140 cycles between −55 °C and room temperature (25 °C)) on the flexural properties of the specimens was also investigated, and the damage caused to the reinforcement layer was directly detected by comparing the interlaminar images. The results of the double cantilever beam (DCB) test and the end notched flexure (ENF) test were used to verify the optimisation of the interlaminar fracture toughness and flexural properties of the new composite film (PES/GO film). The results show that the performance of PES/GO film under both DCB test and ENF test is superior to that of PES film. Regarding the effect of low-temperature cycling on the specimens, the flexural properties of the specimens containing PES/GO films were improved. Finally, the matrix interface and failure mechanism of the interlayer reinforcement were investigated by scanning electron microscopy (SEM).

Exceptional electromagnetic interference shielding using single-walled carbon nanotube/conductive polymer composites films with ultrathin, lightweight properties

The fundamental integrity of electronic devices depends heavily on appropriate electromagnetic protection measures. In this work, thin films of single-walled carbon nanotubes (SWCNTs) and poly(3,4-ethylene dioxythiophene): poly(styrene sulfonate) composites are presented, and their electromagnetic interference shielding effectiveness (EMI SE) is assessed in the X-band frequency range. The films are prepared via a simple benchtop process involving a vacuum filtration followed by a dip-coating. Notably, the composite with the highest thickness, measuring 2.12 μm, achieved the highest EMI SE of 55.53 dB, whereas the thinnest, measuring 0.24 μm, exhibited the highest specific SE divided by thickness (SSE/t) of 2,230,000 dB·cm2·g−1. Additionally, the composites demonstrated excellent physical and chemical stability, maintaining their performance under various harsh conditions. The highest shielding performance of our composite films among reported carbon-based polymer materials is attributed to the complementary spatial arrangement of inherently conducting materials, namely, the SWCNT and the conducting polymer. Our contribution here lays the groundwork for creating lightweight, flexible composites with superior EMI shielding performance, targeting next-generation flexible electronics.

B and Ce composite microalloying for improving high-temperature oxidation resistance of 254SMO super-austenite stainless steel

Aiming at serious oxidation problem of 254SMO super-austenitic stainless steel during hot working, the influence of B and Ce composite microalloying on its oxidation behavior was comparatively investigated at 1050 and 1100 °C. The results demonstrated that the combination of B and Ce can significantly alter the composition of the oxide film in 254SMO. Particularly, B and Ce composite microalloying can effectively promote the diffusion of Cr to the surface, and form a dense Cr2O3 oxide film at a faster rate in the initial stage, which is more conducive to inhibiting the Mo volatilization and thus improving the oxidation resistance of 254SMO steels. Additionally, compared to the 0.005 wt% B (50B) and 0.005 wt% B together with 0.002 wt% Ce (50B + 20Ce) samples, the addition of 0.005 wt% B together with 0.005 wt% Ce (50B + 50Ce) had a more significant effect on improving high-temperature oxidation resistance of 254SMO. This research provides a valuable scholarly reference for improving the oxidation resistance of super-austenite stainless steels.

Poly(vinylidene fluoride-trifluoroethylene)/graphene composite pressure sensors and their potential applications in sports training

Pressure sensors based on advanced materials have gained high attention for their potential applications in various fields, including sports training. This study focuses on the development of poly(vinylidene fluoride-trifluoroethylene) (P(VDF-TrFE))/graphene composite films as high-performance pressure sensors. The composite films were fabricated using a casting method, and their morphological, structural, thermal, mechanical, and electrical properties were comprehensively characterized. The incorporation of graphene nanoplatelets (GnPs) into the P(VDF-TrFE) matrix led to the formation of a percolated conductive network, resulting in enhanced electrical conductivity and pressure sensitivity. The composite film containing 5 wt% GnP exhibited remarkable sensing capabilities, boasting an elevated sensitivity of 0.85 kPa−1, a rapid response time of 50 ms, and exceptional resilience over 1000 loading-unloading cycles. Moreover, the incorporation of GnP substantially augmented the mechanical properties, with a 65 % enhancement in tensile strength and a 92 % surge in Young's modulus when juxtaposed against pristine P(VDF-TrFE) films. The superior property of these P(VDF-TrFE)/graphene composite pressure sensors, along with their excellent mechanical properties, make them promising candidates for sports training applications, enabling the monitoring and analysis of various biomechanical parameters to optimize athletic performance and prevent injuries.

Preparation of PBAT microplastics and their potential toxicity to zebrafish embryos and juveniles

The extensive use of traditional non-biodegradable plastics results in the generation of microplastics (MPs), forming a new pollutant that can pose significant environmental risks. Biodegradable plastics (BP) possess degradation properties and can partially replace conventional plastics, thereby reducing pollution. However, further investigation is needed into the toxicity of biodegradable microplastics (BMPs) on aquatic organisms. This study explores the toxic effects of PBAT microplastics (PBAT-BMPs) and microplastics produced from degradable PBAT/TPS (thermoplastic starch) composite film (PBAT/TPS-BMPs) on zebrafish embryos. Our findings indicate that the presence of microplastics on the embryo's surface increases with higher BMP concentration. Nonetheless, PBAT-BMPs tend to aggregate and are blocked by the embryonic membrane, thus diminishing their toxic effects on the embryo. Acute toxicity experiments revealed that 30 mg/L of PBAT-BMPs significantly reduced the survival rate of zebrafish embryos, whereas PBAT/TPS-BMPs had a lesser effect on survival. Both types of BMPs influenced the hatching rate of the embryos, leading to prolonged incubation periods. Additionally, both types of BMPs impacted the locomotor behavior of zebrafish larvae, causing an increase in larval locomotor speed. However, these BMPs had little impact on larval body development and heartbeat behavior. Fluorescent microplastic tracer experiments demonstrated that PBAT-BMPs persisted in juvenile fish for at least 144 hours and were difficult to metabolize and excrete. Our study aims to gain a better understanding of the potential effects of BMPs on aquatic ecosystems and biological health, as well as to propose effective strategies for reducing environmental pollution and protecting organisms.

Biodegradable active composite film based on pea protein isolate, sage seed gum, and cumin essential oil: Fabrication and characterization

The present study perused the physicochemical, mechanical, thermal, barrier, and optical properties of pea protein isolate (PPI)-Sage seed gum (SG) (3:1, 1:1, and 1:3) composite films incorporated with cuminum essential oil (CEO, 0, 1, and 2 %). Results indicated that the thickness, contact angle (CA), yellowness index (a*), total color differences (∆E), and opacity (OP) significantly enhanced with increasing PPI portion and CEO concentration (p < 0.05), as well as heterogeneous and inconsistent structure were increased in film surface due to protein agglomeration and oil droplets. However, the moisture content (MC), water solubility (WS), and swelling ratio (SR) decreased. Results also indicated that the antioxidant property significantly increased (P < 0.05) following the increase in CEO concentration. The highest tensile strength (TS) and elastic modulus (EM) and the least elongation at break (EAB) in PPI 3-SG 1–0 % were estimated. The potential antimicrobial property of CEO containing film was confirmed, and the maximum inhibition zone for E.coli, S.aureus, C.albicans, and A.niger were measured in film containing 2 % CEO. The barrier properties of the film against water and oxygen (WVP, OXP) diminished with increases the SG ratios, due to the hydrophilic nature of SG. The FTIR analysis identified the functional groups in film components and the interaction between film components. The DSC thermogram indicated the thermal stability of films and the highest decomposition temperature in PPI 3-SG 1–2 % film. XRD revealed a semi-crystalline structure of biopolymer active films. With the increase of SG portion and CEO concentration, the crystallinity of the films was enhanced. Results also indicated that prepared films were more than 90 % biodegradable.

Examining the potential of peppermint essential oil-infused pectin and kappa-carrageenan composite films for sustainable food packaging

Essential oils are key ingredients in the development of edible films and provide a diverse approach to improving food preservation, as well as sensory qualities. The pectin and kappa-carrageenan composite films were obtained by adding peppermint essential oil in different quantities. The films after their fabrication were thoroughly evaluated for their attributes, which included mechanical, barrier, optical, chemical, thermal, and antioxidant properties. The visual assessment of the films demonstrated that PEO-loaded films showed a uniform, homogenous, and slightly yellowish appearance. There was an increase in the thickness (0.045 ± 0.006 to 0.060 ± 0.008 mm), elongation at break (12.73 ± 0.74 to 25.05 ± 1.33 %), and water vapor permeability (0.447 ± 0.014 to 0.643 ± 0.014 (g*mm)/(m2*h*kPa)) was observed with the addition of PEO. However, tensile strength (45.84 ± 3.69 to 29.80 ± 2.10 MPa) and moisture content (25.83 ± 0.046 to 21.82 ± 0.23 %) decreased with the incorporation of PEO. Furthermore, thermal and antioxidant properties were enhanced by the inclusion of PEO. The presented investigation can be employed to synthesize food packaging material with antioxidant properties with potential applications in food packaging.

Synergy between NiWO4 and chitosan for the development of catalysts for sulfide oxidation

In this work, catalysts based on composite films composed by chitosan with disordered NiWO4 (10, 20, and 40 % w/w) were synthesized for their application in the oxidation of sulfides to sulfones. The catalysts were characterized by X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS), optical profilometry, and contact angle measurements. Optimization of the catalytic conditions was performed using thioanisole as the standard molecule, resulting in optimal conditions of 50°C, 1 h, 10 mg catalyst loading, 8 equivalents of H2O2 as oxidant, and acetonitrile as solvent. The results obtained were superior to those with crystalline NiWO4 (highly ordered), highlighting the crystallinity of the system as a key factor in the development of new catalysts. The catalyst exhibited high stability over successive catalytic cycles, and scaling up to 50 times was achieved. Additionally, the reaction scope showed good conversion for a variety of different sulfides, indicating the robustness of the catalyst. Analysis of the catalytic mechanism through scavenger tests and spectroscopic probes revealed that reactive oxygen species (ROS) are responsible for the oxidation of sulfides to sulfones. Furthermore, it was observed that the synergy between NiWO4 and chitosan is crucial for the effective generation of ROS in this reaction.

Fabrication of N-halamine/MWPPy-ZnO hybrids based cellulose nanofibril composite films with improved UV-protective, antibacterial, and biofilm control functions

The design and fabrication of synergistic hybrid antibacterial materials is a promising approach for achieving effective sterilization while compensating for the deficiency of a single component. Despite being highly effective biocidal components, the poor UV light stability of some N-halamines limits their applications. This study was conducted to address this issue by the rational integration of cyclic N-halamine precursor (PGHAPA) with microwaved zinc oxide (MWPPy-ZnO) nanoparticles via covalent bonds and the preparation of cellulose nanofibrils based antibacterial composite films after chlorination (CNF/MWPPy-ZnO-PGHAPA-Cl). The proposed films offered tight lamellar structure, considerable thermal stability and better mechanical properties. The results from the FT-IR and XPS experiments provided the evidence of chemical reactions among the PGHAPA, MWPPy-ZnO, and CNF film. Notably, the CNF/MWPPy-ZnO-PGHAPA-Cl films showed improved UV stability with a chlorine content of up to 0.16 % after 24 h of irradiation, which was much greater than that of the CNF/PGHAPA-Cl films. Furthermore, the CNF/MWPPy-ZnO-PGHAPA-Cl films displayed rapid bactericidal activity, inactivating all the contacted Staphylococcus aureus and Escherichia coli O157:H7 strains within 5 min, along with prominent biofilm disruption, indicating great potential for daily food packaging applications.

Effect of InP/ZnS quantum dots aggregation on the kinetics of birefringence recorded in thin azopolymer composite films

The article describes the preparation of new thin film composite materials based on the azopolymer (poly[1-[4-(3-carboxy-4-hydroxyphenylazo)benzenesulfonamido]-1,2-ethanediyl, sodium salt]) doped with three different concentration of InP/ZnS quantum dots with size of 7.5 nm. Clusters of aggregated InP/ZnS were microscopically observed in the fabricated composite samples. Birefringence (Δn) was induced in the films at two different wavelengths of the pump laser (355 nm and 444 nm) and the obtained higher values of Δnmax for the samples doped with quantum dots up to 2 wt% in comparison to the non-doped film and the sample with the highest nanocrystals concentration are discussed, based on the measured fluorescence spectra, in terms of possible local energy transfer between the azobenzene chromophores and the InP/ZnS quantum dots.

Automatic segmentation of microporous defects in composite film materials based on the improved attention U-Net module

ABSTRACT Composite film materials offer several advantages, such as high strength-to-weight ratios, flexibility, durability, or cost-effectiveness, which make them ideal for a wide range of applications across various industries. However, microporous defects in the material compromise its durability and air-tightness. Thus far, few works have been performed on inquiring non-destructive testing methods intended for the detection of microporous defects in composite film materials. In this study, the automatic detection of microporous defects is achieved by using a thermal imaging inspection system developed on the basis of a laser infrared system and the U-Net. Innovatively, an improved attention module is added to U-Net to boost its detection performance. While using a laser as a heat source, a fibre laser beam shaper is chosen as the laser beam expansion to ensure a uniform intensity distribution of the laser beam within a small heating area. Experimental results show that the proposed method can reliably detect microporous defects in the composite film materials with sizes in the order of millimeters/micrometers.

Influence of non-linear diffusion controlled phenomena on the sorption capability of PEO-Salt-SiO2 composite electrolyte: A study on property optimization

The present research, reports the hygrothermal behavior of poly [ethylene oxide] (PEO) based composite film (500 and1000 μm) containing NH4I and KBr (5–20 wt%) as the mobile phase and non-reactive silica (15 wt%) as the filler. These are termed as PK/NSiO2-series for solvent sorbed and (PK/NSiO2)NS for non-swelled film. The novelty of the research lies in the analyses of non-Fickian solvent diffusion trait of films using python programming. The presence of ions and its variable polarizable nature is found to influence the number density of bonded and free solvent content along with the extend of cross linkage. Introduction of silica is found to enhance the ionic conductivity (about one order higher) of the film irrespective of the type of charge carrier owing to the improved dispersion within the matrix. Non-Fickian diffusion is found to influence the ionic conductivity of P2K20SiO2 (10−5Scm−1 to 10−2 Scm−1) minimizing the degradation to 0.2 %ΔC/1000 h (>1 %ΔC/1000 h, tested for 2000 h) compared to P2N20NSiO2. In contrast, ion migration in P2NSiO2 is guided by Rice and Roth model and being more polarizable ions, the mobility is significant which maximizes the conductivity to ∼10−1 Scm−1. Microstructural study shows heterogenous nucleation to be more pronounced upon addition of silica filler wherein the homogeneity, inter fibrillar interaction and grain growth of spherulites is higher. This tends to extend amorphous regions thereby propagating the ion migration path. The influence of sorption process is studied in terms of electrochemical impedance, dielectric analyses and long term cyclability (20,000 h) in terms of loss tangent.

Strategies for alkali-free synthesis, surface modification, and electrophoretic deposition of composite films for biomedical applications

This investigation addresses increasing interest in composites for biomedical applications and advanced methods for their synthesis and electrophoretic deposition (EPD). The feasibility of preparation of hydroxyapatite (HA), titania and zirconia particles using branched polyethylenimine polymer (BPEI) or L-arginine amino acid as organic alkalizers is demonstrated. In this new approach, BPEI and L-arginine are used as alkalizers-capping agents instead of inorganic alkalis. The use of BPEI facilitates synthesis of HA nanorods with reduced size. This approach opens an avenue for the fabrication of nanoparticles of other functional inorganic materials using alkalizers-capping agents. It offers advantages of simple procedure, environmental benefits and improved control of particle size. Composite films are obtained by cathodic EPD using linear polyethylenimine (LPEI) as a charging and film-forming agent. A conceptually new approach is developed for anodic EPD of alginic acid polymer (AlgH) and composite films containing drug molecules in AlgH matrix. This strategy involves the use of L-arginine as an alkalizer for solubilization of drugs, which exhibit poor solubility in water. AlgH and drug molecules are solubilized in water and deposited by anodic EPD. Testing results confirm the fabrication of composite films, containing drug molecules. This method allows reduced gas evolution at the electrode, elimination of film porosity, improved stabilization of bioceramic particles in polymer solutions and facilitates composite film formation from stable suspensions. The deposition methods developed in this investigation can be used for deposition of other cationic and anionic polymers and their co-EPD with bioceramics, drugs and other functional materials.

Optimizing pH sensor performance with PANI/PMMA composite thin films: Impedimetric and capacitive transduction approaches

The continuous search for novel materials to meet the requirements of modern technological applications has led to the widespread use of polyaniline (PANI) composites for sensing purposes. Although research has been carried out on both chemical sensors using PANI/polymer composites and chemical sensors with impedimetric/capacitive transduction using PANI composites, there is still a gap in the use of PANI/polymer composites in impedimetric and capacitive transduction platforms for pH sensing. In this study, the influence of composite thin films consisting of PANI and poly(methyl methacrylate) (PMMA) on the sensitivity and linearity of pH sensors based on electrochemical impedance and capacitance spectroscopy (EIS/ECS) was evaluated. The sensitivity and linearity of the devices showed a dependence on the polymer content. For PANI:PMMA equal to 30:70, the EIS and ECS sensitivity reached 12.6 ± 2.7 and 18.7 ± 4.9 %/pH, respectively, after reaching its minimum value for the 50:50 sample. Similarly, the linearity values for the 30:70 sample were 92.7 % and 99.8 % for EIS and ECS, respectively. We were able to encapsulate the PANI in the PMMA matrix, which improved the control of ion diffusion and analyte access to the active redox quinoid rings on the PANI. As a result, the saturation effect of the polymer was reduced. By adjusting the relative content of PANI and PMMA, the structure and properties of the composite can be controlled, directly affecting the sensor parameters. These materials have potential applications in sensors for various fields such as food, biomedical and environmental monitoring, with the ability to tailor their properties for optimal response.

Preparation and tribological properties of PAI/PTFE@Mg-Al LDH polymer-based solid self-lubricating materials

PAI/PTFE composites with 1 %, 2 %, 3 %, 4 % and 5 % of Magnesium aluminum hydrotalcite (Mg-Al LDH) particles were prepared by DC electric field-assisted hot-pressing sintering. The friction and wear properties of the composites were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), thermogravimetric analysis (TGA), water contact angle and UMT-5 friction and wear tests. The effect of the amount of Mg-Al LDH particles added on the physical properties and friction and wear properties of the composites were analyzed. Experimental results showed that the friction and wear properties of PAI/PTFE composite films can be improved by adding appropriate Mg-Al LDH particles. Among them, The PAI/PTFE polymer based solid lubrication containing 3 % Mg-Al LDH has the best friction coefficient and wear amount, the average friction coefficient is 0.0962 and the wear extent is 1.47×10−5 g. The improved tribological properties of the composite films are mainly due to the excellent mechanical properties of Mg-Al LDH and the good lubrication properties of PTFE.

Reconfigurable light-responsive liquid crystal elastomer /carbon nanotube nanocomposite actuators operated by photothermal effects and dynamic exchange reaction

Monodomain liquid crystal elastomers (MLCEs), exhibiting a light-induced dynamic exchange reaction (DER) and light-triggered actuation abilities, were prepared using dispersed multiwalled carbon nanotubes (MWCNTs) and allyl sulfide linkages incorporated in the MLCE matrix. MWCNTs were dispersed in the MLCE matrix using a newly synthesized dispersant, poly(4-cyanobiphenyl-4′-oxyundecylacrylate-co-pyrene methyl acrylate); this dispersant exhibited amphiphilic properties of π–π interactions with the MWCNT fillers (attributed to the pyrene moieties) and miscibility with the MLCE matrix (attributed to the cyanobiphenyl mesogenic moieties). A low amount of well-dispersed MWCNTs (≤0.05 wt%) in the MLCE matrix induced excellent photothermal effects under near-infrared (NIR) light irradiation, leading to considerable reversible contraction/extension actuation (∼40 % change in length). The bilayer film comprising the MLCE and PLCE (PLCE: polydomain LCE) composite films bonded via DER without glue exhibited excellent bending actuation under NIR light irradiation and was configured into several actuators such as a flower-shaped actuator, a weightlifter, a circular rolling band, an oscillator mimicking a hummingbird, and a casting catapult. Therefore, this novel MLCE/CNT composite film enhances the design ability for the arbitrary shaping and functionalization of NIR light-triggerable LCE actuators, which can be applied to several interesting soft robots.

Nacre inspired supertough and flame-retardant reduced graphene oxide composite films

Nacre-like graphene composite films (GCFs) with high strength have been highly developed. However, the GCFs usually exhibit relatively poor toughness and poor flame resistance, seriously limiting their applications as structural materials. Here, reduced graphene oxide (rGO), halloysite nanotubes (HNTs), and flame-retarding modified lignin (F-lignin) were compounded to fabricate the rGO-HNTs-(F-lignin) film. In the rGO-HNTs-(F-lignin) film, the F-lignin binds the rGO sheets and HNTs, enhancing the entanglement of HNTs and the interactions between HNTs and rGO sheets, and the macromolecular F-lignin also improves the ductility of the rGO-HNTs-(F-lignin) film, while the entangled HNTs conversely reinforce the F-lignin to prevent the F-lignin from fracture when the rGO-HNTs-(F-lignin) film is under stress, further increasing the ductility of the rGO-HNTs-(F-lignin) film. The HNTs and F-lignin promote each other to enhance the strengthening and toughening effect on the rGO-HNTs-(F-lignin)-film, and endowing the rGO-HNTs-(F-lignin)-film with the superior mechanical properties of the tensile strength of 634 ± 38 MPa, tensile fracture strain of 8.17 ± 0.59 %, and toughness of 25.35 ± 2.95 MJ/m3, respectively. The rGO-HNTs-(F-lignin) film also exhibits improved flame-retardant properties due to the high flame retardancy of HNTs and F-lignin. These excellent integrated properties of the rGO-HNTs-(F-lignin) film will promote its potential applications as structural materials.

Fabrication of a versatile and efficient ultraviolet blocking biodegradable composite film consisting of Tara gum/PVA/Riceberry phenolics reinforced with biogenic riceberry phenolic-rich extract-nano‑silver

The demand for UV-protective and biodegradable packaging materials has been increasing with greater awareness about environmental sustainability and human safety. In this work, the effect of incorporating riceberry phenolic extract (RPE) as well as combined RPE and green synthesized biogenic nano‑silver (RPE-NS, into Tara gum/PVA (TP)-based matrix was evaluated on the physical, mechanical, functional, biocompatible and biodegradable attributes of the resultant composite films. Integration of RPE (2 wt%) and RPE-NS (0.8 wt%) resulted in nanocomposite (TP/RPE-NS) film with improved physical properties relative to the plain TP and TP/RPE films. The TP/RPE-NS film displayed a compact structure and homogenous distribution of the nano‑silver. Increased molecular interactions, crystallinity and thickness was also observed for the nanocomposite film. Compared to plain TP film, TP/RPE-NS film exhibited improved water vapor barrier properties and surface hydrophobicity due to the extract and nanoparticles. The tensile strength and elongation-at-break of TP/RPE-NS were markedly higher (41.76 MPa and 37.40 %) compared to that of plain TP film (36.07 MPa and 20.80 %). Whereas TP/RPE film provided good UV protection (UPF value of 31.85) compared to the minimal protection by TP film (UPF value of 2.72), combination of RPE/RPE-NS ensured that TP/RPE-NS availed an excellent UV-barrier performance (UPF value of 61.09). Furthermore, TP/RPE-NS film exhibited significant antioxidant activity relative to TP film. Besides, all TP-based films were found to be compatible with rat erythrocytes and biodegradable. Taken together, these findings indicate that TP/RPE-NS holds good potential for the development of UV-protective and biodegradable packaging material.

Enhanced performance of ambient-air processed CsPbBr3 perovskite light-emitting electrochemical cells via synergistic incorporation of dual additives

Metal halide perovskite light-emitting electrochemical cells (MHP-LECs) are promising due to their facile solution processability and exceptional optoelectrical properties. However, commercialization is hindered by poor thin-film coverage and the need for glovebox processing. This study addresses these issues by incorporating poly(ethylene oxide) (PEO) and potassium hexafluorophosphate (KPF6) into cesium lead bromide perovskite (CsPbBr3) emitting layers (EML), processed under ambient-air conditions. These perovskite composite thin films were spin-coated on a preheated substrate, and the device structure was ITO/PEDOT:PSS/EML/Al. Notably, the MHP-LEC based on CsPbBr3:PEO:KPF6 (100:65:0.2, weight ratio) exhibited pure-green emission with a peak at 524 nm and a narrow full width at half-maximum of 27 nm. Compared to a reference device (CsPbBr3:PEO (100:65, weight ratio)), the new device showed 1.5-, 4-, and 5-fold improvements in current density, electroluminescence (EL) intensity, and lifetime, respectively. These enhancements are attributed to reduced non-radiative current leakage, improved film surface coverage and passivation, and balanced charge carrier injection and transportation. This study offers a straightforward approach for processing CsPbBr3 thin films under ambient-air conditions, enhancing the EL performance of MHP-LECs.