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Metal‐halide perovskites (PSKs) are emergent materials for a large range of applications, and the layered double PSK architectures vastly enrich the opportunities to design their composition, structural properties, and optoelectronic behavior. The stability, crystal phase, and electronic bandgap depend strongly on the bonds and distortions of the octahedra lattice that are at the origin of the vibrational spectrum of these materials. This work investigates the structural dynamics of flakes of exfoliated layered Ag‐Bi bromide double PSKs by angle‐dependent polarized Raman spectroscopy and density functional theory modeling. The well‐defined orientation of the inorganic octahedra lattice with respect to the light polarization allows to correlate the angle‐dependent intensity of the Raman signal to the directionality and symmetry of the phonon modes. Low‐frequency vibrations are revealed for which a detailed microscopic and group theory assignment of the Raman modes is provided. The temperature‐dependent measurements across the phase transitions show marked changes in the phonon frequencies, reveal soft modes, and help to distinguish first from second‐order transitions as well as to determine their transition temperature. This provides highly valuable insights to improve the properties of this class of Pb‐free PSKs for applications in energy harvesting and optoelectronics. [ABSTRACT FROM AUTHOR]

[Display omitted] • LC-HRMS was used for the detection of metabolites of the two co-formulants. • Three and five metabolites were found from the two co-formulants in vegetables. • Three metabolites were more toxic than their original molecule. • Most metabolites are persistent, detected at 21 days with high concentrations. Plant protection products contain co-formulants that could end up in vegetables, and they can generate transformation products that can be more toxic than their original molecule, which are a potential risk to food safety. Therefore, this study evaluated the dissipation of two co-formulants, dodecylbenzenesulfonic acid and 1-ethyl-2-pyrrolidone, in courgette and tangerine samples to determine possible harmful metabolites under laboratory conditions. The analyses of these substances were performed by liquid chromatography coupled to quadrupole-Orbitrap high-resolution mass spectrometry (LC-Q-Orbitrap-HRMS). For the degradation of both compounds, a single-phase kinetic model was fitted, with R2 values greater than 0.99. In courgette and tangerine, half-lives (DT 50) for dodecylbenzene sulfonic acid were 1.83 and 1.42 days, while DT 50 was 6.26 and 5.04 days for 1-ethyl-2-pyrrolidone, respectively. Three metabolites of dodecylbenzenesulfonic acid and five metabolites of 1-ethyl-2-pyrrolidone were found in courgette, while the same metabolites were detected in tangerine samples, except benzoic acid and 4-aminobutanoic acid. These metabolites were identified for the first time from these compounds except for benzoic acid, observing that 5-hydroxy-N-ethylpyrrolidone was the most concentrated metabolite in tangerine 14 days after application, reaching a maximum concentration of 149 µg/kg. Furthermore, some of the detected metabolites possessed a value of LD 50 lower than their original molecules. In consequence, such metabolites, derived from these co-formulants, should be controlled to prevent negative health effects, and ensure food safety. [ABSTRACT FROM AUTHOR]

[Display omitted] • LC and GC-HRMS were used to detect co-formulants present in PPPs in food. • Suspect analysis allowed the tentative identification of 37 co-formulants. • Twenty one co-formulants were quantified in fruits, vegetables and leaves. • 1-Ethyl-2-pyrrolidone was identified in all samples and at high concentrations. • Some compounds were declared as unsuitable co-formulants because their toxicity. Vegetables can contain co-formulants derived from the use of plant protection products (PPPs) in crops. Thus, in the current study co-formulants were determined in different fruits and vegetables and their leaves by gas and liquid chromatography coupled to Q-Orbitrap high-resolution mass spectrometry (GC-Q-Orbitrap and LC-Q-Orbitrap-MS). A total of 37 co-formulants were tentatively identified, and among them, 12 compounds were quantified by LC-Q-Orbitrap-MS and 9 by GC-Q-Orbitrap-MS. The mean co-formulant levels in fruit and vegetable samples was 92% lower than in leaf samples. Selected samples showed a high concentration of 1-ethyl-2-pyrrolidone among the co-formulants detected. This compound ranged from 22 µg/kg (strawberry) to 722 µg/kg (red grape), whereas in the case of leaves, its concentration was up to 6513 µg/kg in cucumber leaf. In addition, it has an LD 50 equal to 1.440 g/kg. Therefore, this type of PPP co-formulants should be controlled in fruits and vegetables to avoid adverse health effects. [ABSTRACT FROM AUTHOR]

Mixed‐dimensional systems host interesting phenomena that involve electron and ion transport along or across the interface, with promising applications in optoelectronic and electrochemical devices. Herein, a heterosystem consisting of a graphene monolayer with a colloidal Ag2S nanocrystal film atop, in which both ions and electrons are involved in photoelectrical effects, is studied. An investigation of the transport at the interface in different configurations by using a phototransistor configuration with graphene as a charge‐transport layer and semiconductor nanocrystals as a light‐sensitive layer is performed. The key feature of charge transfer is investigated as a function of gate voltage, frequency, and incident light power. A simple analytical model of the photoresponse is developed, to gain information on the device operation, revealing that the nanocrystals transfer electrons to graphene in the dark, but the opposite process occurs upon illumination. A frequency‐dependence analysis suggests a fractal interface between the two materials. This interface can be modified using solid‐state electrochemical reactions, leading to the formation of metallic Ag particles, which affect the graphene properties by additional doping, while keeping the photoresponse. Overall, these results provide analytical tools and guidelines for the evaluation of coupled electron/ion transport in hybrid systems. [ABSTRACT FROM AUTHOR]

The fabrication of electrochemical double-layer capacitors (EDLCs) with high areal capacitance relies on the use of elevated mass loadings of highly porous active materials. Herein, we demonstrate a high-throughput manufacturing of graphene/carbon nanotubes hybrid EDLCs. The wet-jet milling (WJM) method is exploited to exfoliate the graphite into single-few- layer graphene flakes (WJM-G) in industrial volumes (production rate ca. 0.5 kg/day). Commercial single-/double-walled carbon nanotubes (SDWCNTs) are mixed with graphene flakes in order to act as spacers between the flakes during their film formation. The WJM-G/SDWCNTs films are obtained by one-step vacuum filtration of the material dispersions, resulting in self-standing, metal- and binder-free flexible EDLC electrodes with high active material mass loadings up to around 30 mgcm-2. The corresponding symmetric WJM-G/SDWCNTs EDLCs exhibit electrode energy densities of 539 μWhcm-2 at 1.3 mWcm-2 and operating power densities up to 532 mWcm-2 (outperforming most of the reported EDLC technologies). The EDCLs show excellent cycling stability and outstanding flexibility even in highly folded states (up to 180°). [ABSTRACT FROM AUTHOR]

Abstract Pentacyclic triterpenes play an important role in plant defense and have demonstrated beneficial effects in human health acting in disease prevention. In the present study, the determination of triterpenes compounds in olive leaves of six different cultivars grown at four dates was assessed in order to corroborate the influence of olive growth cycle on triterpenes content and to evaluate if the highest amounts are detected in correspondence to the olive oil production period when the leaves are one of the most important by-product. A GC-QTOF-MS methodology was optimized and validated, and five triterpenes were identified and quantified in all olive leaves samples analysed. ANOVA analyses revealed quantitative differences among sampling times and cultivars. Principal Component Analyses showed a good separation among triterpenes content for the different collecting seasons and cultivars. Picual, the most commonly grown olive today for olive oil production, was the cultivar that presented the highest concentrations of triterpenes and oleanolic acid the major triterpene in all cultivars at all sampling times (54–76.5% of total triterpenes). The triterpenes concentration is higher in June than in the other sampling times. Unfortunately, the leaves sampled at the stage that corresponded to the olive oil production were not the best one in terms of triterpenes content; however the decrease was never >15.5%. Thus, the present results confirm olive leaves a suitable source of bioactive compounds that can be used to obtain high added-value products enriched in triterpenes. Graphical abstract Unlabelled Image Highlights • GC-qTOF-MS was successfully used for triterpenic compounds determination in olive leaves. • Picual presented the highest concentrations of triterpenes. • PCA discriminates olive leaves according to their cultivar and harvest time [ABSTRACT FROM AUTHOR]

PbS nanocrystals are an important narrow-gap material for solar cells and photodetectors. Nevertheless, their application may be limited because device performance can be affected by atmospheric conditions. Indeed, the presence of oxygen and/or water can degrade the active layers, possibly leading to device failure. Strategies to address this issue are therefore actively explored. Here we report a solution-processed PbS quantum dot solar cell, consisting of a PbS-silane functionalized reduced graphene oxide (PbS-rGO) layer on top of the PbS absorber film, which enhances device stability, especially when the solar cells are exposed to moisture. Power conversion efficiency (PCE) measurements demonstrate a slower degradation under continuous illumination for solar cells with PbS-rGO. When storing the samples under saturated water vapor, differences are even more remarkable: with PbS-rGO the solar cells essentially maintain their initial PCE, while the PCE of the PbS reference devices is reduced by 50% after 5 days. Scanning electron microscopy, energy dispersive X-ray and X-ray photoelectron spectroscopy reveal the damage to the PbS films and the formation of PbSO x crystals in the PbS reference devices. Such crystals are not observed in the PbS-rGO devices, further supporting the importance of the PbS-rGO barrier layer. [ABSTRACT FROM AUTHOR]

Two different gas chromatography coupled to quadrupole-time of flight mass spectrometry (GC-QTOF-MS) methodologies were carried out for the analysis of phytosterols and tocopherols in the flesh of three mango cultivars and their by-products (pulp, peel, and seed). To that end, a non-polar column ((5%-phenyl)-methylpolysiloxane (HP-5ms)) and a mid-polar column (crossbond trifluoropropylmethyl polysiloxane (RTX-200MS)) were used. The analysis time for RTX-200MS was much lower than the one obtained with HP-5ms. Furthermore, the optimized method for the RTX-200MS column had a higher sensibility and precision of peak area than the HP-5ms methodology. However, RTX-200MS produced an overlapping between β-sitosterol and Δ5-avenasterol. Four phytosterols and two tocopherols were identified in mango samples. As far as we are concerned, this is the first time that phytosterols have been studied in mango peel and that Δ5-avenasterol has been reported in mango pulp. α- and γ-tocopherol were determined in peel, and α-tocopherol was the major tocopherol in this fraction (up to 81.2%); however, only α-tocopherol was determined in the pulp and seed. The peel was the fraction with the highest total concentration of phytosterols followed by seed and pulp, and "Sensación" was the cultivar with the highest concentration of total phytosterols in most cases. There were no significant differences between quantification of tocopherols with both columns. However, in most cases, quantification of phytosterols was higher with RTX-200MS than with HP-5ms column. [ABSTRACT FROM AUTHOR]

We investigated the effect of cation exchange on the anionic framework of lightly doped CdSe:Te/CdS nanorods. In contrast with previously studied core/shell systems, the Te dopant, located in the center of the CdSe core, provides an extremely sensitive indicator for any structural changes of the anionic framework that may occur as a result of the cation exchange process. We first optimized the cation exchange procedure in order to retain the fluorescence properties of the CdSe:Te/CdS nanorods after exchange of Cd2+ for Cu+ and back to Cd2+. Next, using multiexciton spectroscopy, we were able to probe the magnitude of the exciton-exciton repulsion interaction and use that to assess the degree of crystal structure conservation. Our findings provide a much stronger proof that the anion framework is indeed rigid, showing no evidence of significant migration of the anionic dopant. [ABSTRACT FROM AUTHOR]

Aerocelluloses are considered as “third generation” aerogels after the silica and synthetic polymer-based ones. However, their brittleness and low optical translucency keep quite narrow their fields of applications. Here, both issues are addressed successfully through the fabrication of flexible and mechanically robust amorphous aerocellulose with high optical transparency, using trifluoroacetic acid as a solvent and ethanol as a non-solvent. The developed aerocellulose displays a meso-macroporous interconnected nanofibrous cellulose skeleton with low density and high specific surface area. We demonstrate its high efficiency as supporting matrix for nanoscale systems by incorporating a variety of colloidal quatum dots, that provide bright and stable photoluminescence to the flexible aerocellulose host. [ABSTRACT FROM AUTHOR]

Keywords: anisotropy; double perovskites; layered metal-halide perovskites; phase transitions; polarized Raman spectroscopy; vibrational modes EN anisotropy double perovskites layered metal-halide perovskites phase transitions polarized Raman spectroscopy vibrational modes 1 1 1 07/20/22 20220718 NES 220718 Layered metal-halide double perovskite structures are promising lead-free materials for optoelectronics. Low-Frequency Phonon Modes in Layered Silver-Bismuth Double Perovskites: Symmetry, Polarity, and Relation to Phase Transitions (Advanced Optical Materials 14/2022) Anisotropy, double perovskites, layered metal-halide perovskites, phase transitions, polarized Raman spectroscopy, vibrational modes. [Extracted from the article]

Wepropose to use the self-assembly ability of a block copolymer combinedwith compression–expansion cycles to obtain CdSe quantum dots(QDs) structures of different morphology. The methodology proposedconsists in transferring onto mica mixed Langmuir monolayers of QDsand the polymer poly(styrene-co-maleic anhydride)partial 2-butoxyethyl ester cumene terminated, PS-MA-BEE, previouslysheared by 50 compression–expansion cycles. Results indicatethat the shear stress takes out nanoparticles at the air–waterinterface from metastable states and promotes a new equilibrium stateof the Langmuir monolayer. This new state was transferred onto micaby the Langmuir–Blodgett (LB) methodology, and the morphologyof the LB films was analyzed by atomic force microscopy and transmissionelectron microscopy measurements. Our results show that when the amplitudestrain increases, the QDs domain size decreases and the QDs LB filmarrangement becomes more ordered. The dynamics of the monolayer relaxationafter cycling involves at least three time scales which are relatedto the damping of surface fluctuation, raft rearrangement, and componentmovements inside each raft. Brewster angle microscopy allowed visualizing in situthe raft rearrangement at the air–water interface. [ABSTRACT FROM AUTHOR]

Abstract: We propose to use the self-assembly ability of a block copolymer to obtain CdSe quantum dots (QDs) structures of different morphology. The methodology proposed consist in transferring mixed Langmuir monolayers of QDs and the polymer poly (styrene-co-maleic anhydride) partial 2 buthoxy ethyl ester cumene terminated, PS-MA-BEE onto mica by the Langmuir–Blodgett (LB) methodology. The morphology of the LB films was analyzed by AFM and TEM measurements. Our results show that it is possible to modulate the self-assembly process by modifying the composition of the mixed Langmuir monolayer precursor of the LB film. The different morphologies are interpreted according to two different dewetting mechanisms, growth of holes and spinodal-like dewetting. The growth of holes dewetting process is driven by gravitatory effects and was observed for LB films obtained by transferring Langmuir monolayer of the smallest elasticity values in which the polymer is in brush conformation. The spinodal dewetting mechanism prevailed when the Langmuir monolayer presents the highest elasticity values. [Copyright &y& Elsevier]

Air classification is a valuable process to obtain flours enriched in phenolic compounds. In this study, dehulled buckwheat grain flour was micronized and air classified obtaining two couple of fractions with different yields (fine fraction 70% and coarse fraction 30%, and fine fraction of 80% and coarse fraction 20%). The total content of phenolic compounds (by HPLC-MS) in coarse fractions increased 1.7–2.1 times compared to fine fractions. In addition, coarse fractions have shown a total phenolic content of 1.4–1.7 times more than dehulled buckwheat flour. Moreover, the antioxidant activity was evaluated using two different assays: FRAP (The ferric reducing antioxidant power) and DPPH (2,2-diphenyl-1-picrylhydrazyl radical). Coarse fractions have shown FRAP values 1.2–1.3 times higher than fine fractions, whereas the DPPH showed a slight increase in coarse fractions in comparison with buckwheat flour and fine fractions. In addition, FRAP and DPPH have exhibited a significative positive correlation with the flavonoids, phenolic acid derivatives and total phenolic content. These results have shown that air classification is an effective technique in order to obtain coarse flour fractions enriched in phenolic compounds such as swertimacroside, (epi)-afzelchin-(epi)-catechin- O -dimethyl gallate, rutin and caffeic acid hexose, among others. • Phenolic compounds content enrichment of buckwheat flour is possible by air classification. • Phenolics in buckwheat coarse fractions was 1.4–1.7 times higher than whole flours. • Buckwheat coarse fractions showed high antioxidant activity. • Phenolic compounds decreased in fine fractions. [ABSTRACT FROM AUTHOR]

Hawthorn leaves are a rich source of phenolic compounds that possess beneficial activities for human health. Ultrasonic-assisted extraction (UAE) is an extraction technique frequently used for the isolation of phenolic compounds in plants. Thus, in this study, a Box–Behnken design was used to optimize UAE conditions such as the percentage of acetone, the extraction time and solvent-to-solid ratio (v/w) in order to obtain the maximum content of total compounds by Folin–Ciocalteu and the maximum in vitro antioxidant activity by DPPH, ABTS and FRAP assays in Crataegus monogyna leaves. The optimum conditions to obtain the highest total phenolic content and antioxidant activities were 50% acetone, 55 min and 1/1000 (w/v). A total of 30 phenolic compounds were identified and quantified in C. monogyna leaf extract obtained at these optimum UAE conditions. HPLC-MS allows the identification and quantification of 19 phenolic compounds and NP-HPLC-FLD analyses showed the presence of 11 proanthocyanidins. According to the results, the most concentrated phenolic compounds in C. monogyna leaf extract obtained at optimum UAE conditions were phenolic acid derivatives such as protocatechuic acid-glucoside, dihydroxy benzoic acid pentoside and chlorogenic acid, flavones such as 2″-O-rhamnosyl-C-hexosyl-apigenin, flavonols such as hyperoside and isoquercetin and proanthocyanidins such as monomer and dimer. As a result, the optimized UAE conditions could be used to obtain an extract of C. monogyna leaves enriched with phenolic compounds. [ABSTRACT FROM AUTHOR]

The inorganic content and the catalytic performance pose metal‐loaded enzyme nanoflowers as promising candidates for developing bioelectrodes capable of functioning without the external addition of a redox mediator. However, these protein‐inorganic hybrids have yet to be successfully applied in combination with electrode materials. Herein, the synthesis procedure of these bionanomaterials is reproposed to precisely control the morphology, composition, and performance of this particular protein‐mineral hybrid, formed by glucose oxidase and cobalt phosphate. This approach aims to enhance the adherence and electron mobility between the enzyme and a carbon electrode. The strategy relies on dressing the protein in a tailored thin nanogel with multivalent chemical motifs. The functional groups of the polymer facilitate the fast protein sequence‐independent biomineralization. Furthermore, the engineered enzymes enable the fabrication of robust cobalt‐loaded enzyme inorganic hybrids with exceptional protein loads, exceeding 90% immobilization yields. Notably, these engineered biohybrids can be readily deposited onto flat electrode surfaces without requiring chemical pre‐treatment. The resulting bioelectrodes are robust and exhibit electrochemical responses even without the addition of a redox mediator, suggesting that cobalt complexes promote electron wiring between the active site of the enzyme and the electrode. [ABSTRACT FROM AUTHOR]

Therapeutic deep eutectic solvents (THEDES) are an emerging family of eutectic mixtures gaining increasing interest in the biomedical space. The immobilization of THEDES into polymer networks allows bioactive eutectogels to expand their application scope to topical drug delivery. Herein, this work presents the first set of elastomeric eutectogels constructed by supporting a therapeutic eutectic system with skin permeation ability in a protein scaffold dynamically crosslinked by a natural polyphenol. In this ionic eutectic, gelatin undergoes gelation through an unexpected mechanism in striking contrast with classical hydrogels, which is herein thoroughly studied. Interestingly, the polyphenol controls the conformation of the protein structure, enabling tuning up the mechanical and viscoelastic behavior of the dynamic eutectogel networks from elastic to hyperelastic. The resultant protein eutectogels exhibit strain‐hardening behavior, thermoreversible gel‐to‐sol transition, and excellent adhesive performance. Furthermore, these versatile materials retain the bioactivity of the liquid THEDES and favor skin occlusion, assisting the delivery of both hydrophilic and hydrophobic substances in ex vivo porcine skin in a time‐dependent penetration process. These ultrastretchable eutectogels show new interplays between protein scaffolds and eutectic mixtures, paving the way for innovative therapeutic soft materials. [ABSTRACT FROM AUTHOR]

Layered hybrid organic–inorganic metal‐halide perovskites (HOIPs) can acquire chirality from molecules incorporated into their structure showing exciting possibilities in optoelectronics and spintronics. However, researchers have focused their attention on the study of bulk compounds, namely unstable and toxic Pb HOIPs. Herein, the chiroptical properties of R‐ and S‐β‐methylphenethylammonium Mn chloride HOIPs are reported in both the bulk and the few‐layer limit as exfoliated flakes. Red photoluminescence (PL) emission originating from the octahedrally coordinated Mn2+ is observed, with a PL shift to longer wavelengths when passing from bulk to flakes. Circular dichroism and circularly polarized PL mirrored‐signals for enantiomers are found in bulk samples, while in flakes, a degree of circularly polarized emission (P) of up to 17% at 80 K is achieved, comparable to Pb‐based HOIPs. Moreover, angle‐resolved PL measurements on flakes show that the PL emission and P are isotropic. These findings highlight the potential of these HOIPs from bulk to flakes for spin‐optoelectronic applications. [ABSTRACT FROM AUTHOR]

Spintronic devices require materials that facilitate effective spin transport, generation, and detection. In this regard, graphene emerges as an ideal candidate for long‐distance spin transport owing to its minimal spin‐orbit coupling, which, however, limits its capacity for effective spin manipulation. This problem can be overcome by putting spin‐orbit coupling materials in close contact with graphene leading to spin‐orbit proximity and, consequently, efficient spin‐to‐charge conversion through mechanisms such as the spin Hall effect. Here, the gate‐dependent spin Hall effect in trilayer graphene proximitized with tin sulfide (SnS) is reported and quantified, a group‐IV monochalcogenide that has recently been predicted to be a viable alternative to transition‐metal dichalcogenides for inducing strong spin‐orbit coupling in graphene. The spin Hall angle exhibits a maximum around the charge neutrality point of graphene up to room temperature. The findings expand the library of materials that induce spin‐orbit coupling in graphene to a new class, group‐IV monochalcogenides, thereby highlighting the potential of 2D materials to pave the way for the development of innovative spin‐based devices and future technological applications. [ABSTRACT FROM AUTHOR]

• Two aleurone fractions were obtained by a dry fractionation process. • Flavonoids and phenolic acid monomers are mainly located in aleurone layer. • Alkylresorcinols and phenolic acid oligomers are concentrated in testa and other pericarp layer. • Aleurone fractions can be used into food formulations to obtain functional foods. Several companies have focused their attention on the development of technologies able to enrich/isolate the wheat aleuronic layer because it is a source of bioactive compounds. In this work two different wheat bran fractions enriched in aleurone (AF1, 55–70% aleurone and AF2, 75–90% aleurone) were obtained by a dry fractionation based on air classification. Free and bound phenolic compounds, and alkylresorcinols were determined in the two fractions by HPLC-DAD-ESI-TOF-MS and GC–MS, respectively. To our knowledge, feruloyl di-hexoside was described for the first time in wheat aleurone and flavonoids were quantified for the first time in this fraction. The results have shown that the most concentrated free phenolic compounds were flavonoids, and AF1 was the fraction that presented the highest flavonoid content; whereas trans ferulic acid was the most abundant bound phenolic acid, which highest content was obtained in AF2. Besides, total content of ferulic acid monomers in AF2 was 33.63% higher than in AF1, whereas total content of ferulic acid dimers/trimers in AF1 was 33.9% higher than in AF2. The highest content of alkylresorcinols was obtained in AF1 and it was 10.30% higher than the obtained in AF2. Therefore, it can be stated that this green technology could be used to produce enriched aleurone fractions as source of phenolic and alkylresorcinol compounds. These fractions could be of great interest for the formulation of enriched foods. [ABSTRACT FROM AUTHOR]

• Pressurized liquid extraction is an efficient technique in the phenolic recovery. • It was carried out the optimization of temperature, percentage of ethanol and time • Phenolic content was analyzed by high performance liquid chromatography. • The highest recovery was with the minimum time and the maximum of ethanol. • Temperature was the most significant variable in the total phenolic content. Olive leaves are important olive by-products due to their high content of phenolic compounds and elenolic acids, which possess antioxidant, antimicrobial, anti‐atherogenic and anti‐inflammatory properties, among others. Thus, pressurized liquid extraction was used to obtain a high recovery of these compounds from olive leaves. A Box-Behnken design was performed to optimize the PLE conditions of temperature (50−200 °C), % ethanol-water (0–100 %) and extraction time (5−20 min) in order to obtain the highest content of simple phenols, secoiridois, flavonoids, elenolic acids, total compounds and extraction yield from olive leaves. Olive leaf extracts were analyzed by high performance liquid chromatography coupled to mass spectrometry (HPLC-MS). The highest content of total compounds was 158.7 ± 0.4 mg g-1 d.w obtained at 105 °C, 100 % ethanol and 5 min, whereas the highest extraction yield was 43 ± 3% obtained at 198 °C, 100 % ethanol and 5 min. Therefore, multi-response analysis was carried out using desirability function to optimize the PLE conditions for both total compounds and yield. These optimal conditions were 138 °C, 100 % EtOH and 5 min obtaining 144 mg g-1 d.w. of total compounds and 42.2 % of yield. The optimal temperature of 138 °C has shown a great phenolic recovery and 100 % ethanol has been shown to be a safe solvent to use in the food industry. In addition, short extraction times (5 min) mean lower energy consumption and lower costs. Therefore, these PLE optimum conditions could be implemented on an industrial scale. [ABSTRACT FROM AUTHOR]

Brewers' spent grain (BSG) is the most abundant by-product obtained from beer production. However, it contains some bioactive compounds such as phenolic compounds, therefore, the valorization of BSG is important to recovery these compounds and reused them as functional ingredients in food industry. Therefore, in this work, pulsed electric field (PEF) has been used as extraction pre-treatment. PEF parameters such as electric field strength E (0.5, 1.5, 2.5 kV/cm), frequency (50, 100, 150 Hz) and total time of treatment (5, 10, 15 s) were optimized in order to maximize the content of flavan-3-ols, flavonoids, phenolic acid derivates and total free phenolic compounds. Optimal conditions to the maximum value of total free phenolic compounds were the following: 2.5 kV/cm, 50 Hz and 14.5 s. Concentrations of total free and bound phenolic compounds from BSG under these PEF optimum conditions were 2.7 and 1.7 times, respectively, higher than in case of the extraction without PEF pre-treatment, indicating an improvement in the phenolic recovery with the use of PEF as a pre-treatment in brewers spent grain samples. • A pretreatment of pulsed electric fields in brewers' spent grain was optimized. • Pulsed electric fields treated samples show higher amounts of free phenolic compounds. • Bound phenolic compounds were more abundant in pulsed electric fields treated samples. [ABSTRACT FROM AUTHOR]

Germanium–tin (GeSn) microdisks are promising structures for complementary metal–oxide–semiconductor‐compatible lasing. Their emission properties depend on Sn concentration, strain, and operating temperature. Critically, the band structure of the alloy varies along the disk due to different lattice deformations associated with mechanical constraints. An experimental and numerical study of Ge1−xSnx microdisk with Sn concentration between 8.5 and 14 at% is reported. Combining finite element method calculations, micro‐Raman and X‐ray diffraction spectroscopy enables a comprehensive understanding of mechanical deformation, where computational predictions are experimentally validated, leading to a robust model and insight into the strain landscape. Through micro‐photoluminescence experiments, the temperature dependence of the bandgap of Ge1−xSnx is parametrized using the Varshni formula with respect to strain and Sn content. These results are the input for spatially dependent band structure calculations based on deformation potential theory. It is observed that Sn content and temperature have comparable effects on the bandgap, yielding a decrease of more than 20 meV for an increase of 1 at% or 100 K, respectively. The impact of the strain gradient is also analyzed. These findings correlate structural properties to emission wavelength and spectral width of microdisk lasers, thus demonstrating the importance of material‐related consideration on the design of optoelectronic microstructures. [ABSTRACT FROM AUTHOR]

Cadmium mercury selenide (CdHgSe) nanocrystals exhibit a unique combination of low‐energy optical absorption and emission, which can be tuned from the visible to the infrared range through both quantum confinement and adjustment of their composition. Owing to this advantage, such nanocrystals have been studied as a promising narrow‐band infrared light emitter. However, the electroluminescence of CdHgSe‐based nanocrystals has remained largely unexplored, despite their potential for emitting light in the telecom wavelength range. Further benefits to their optical properties are expected from their shape control, in particular the formation of 2D nanocrystals, as well as from a proper design of their heterostructures. In this work, a colloidal synthesis of CdHgSe/ZnCdS core/shell nanoplatelets (NPLs) starting from CdSe template NPLs employing a cation exchange strategy is developed. The heterostructures synthesized exhibit photoluminescence that can be tuned from ≈1300 to 1500 nm. These near‐infrared‐active NPLs are employed in light‐emitting diodes, demonstrating low turn‐on voltage and high external quantum efficiency. [ABSTRACT FROM AUTHOR]

When doped into a certain range of charge carrier concentrations, MoS2 departs from its pristine semiconducting character to become a strongly correlated material characterized by exotic phenomena such as charge density waves or superconductivity. However, the required doping levels are typically achieved using ionic‐liquid gating or air‐sensitive alkali‐ion intercalation, which are not compatible with standard device fabrication processes. Here, the emergence of superconductivity and a charge density wave phase in air‐stable organic cation intercalated MoS2 crystals are reported. By selecting two different molecular guests, it is shown that these correlated electronic phases depend dramatically on the intercalated cation, demonstrating the potential of organic ion intercalation to finely tune the properties of 2D materials. Moreover, it is found that a fully developed zero‐resistance state is not reached in few‐nm‐thick flakes, indicating the presence of 3D superconductive paths that are severed by the mechanical exfoliation. This behavior is ascribed to an inhomogeneous charge carrier distribution, which is probed at the nanoscale using scanning near‐field optical microscopy. The results establish organic‐ion intercalated MoS2 as a platform to study the emergence and modulation of correlated electronic phases. [ABSTRACT FROM AUTHOR]

Understanding the structural and magnetic properties in layered hybrid organic‐inorganic metal halide perovskites (HOIPs) is key for their design and integration in spin‐electronic devices. Here, a systematic study is conducted on ten compounds to understand the effect of the transition metal (Cu2+, Mn2+, Co2+), organic spacer (alkyl‐ and aryl‐ammonium), and perovskite phase (Ruddlesden‐Popper and Dion‐Jacobson) on the properties of these materials. Temperature‐dependent Raman measurements show that the crystals' structural phase transitions are triggered by the motional freedom of the organic cations as well as by the flexibility of the inorganic metal‐halide lattice. In the case of Cu2+ HOIPs, an increase of the in‐plane anisotropy and a reduction of the octahedra interlayer distance is found to change the behavior of the HOIP from that of a 2D ferromagnet to that of a quasi‐3D antiferromagnet. Mn2+ HOIPs show inherent antiferromagnetic octahedra intralayer interactions and a phenomenologically rich magnetism, presenting spin‐canting, spin‐flop transitions, and metamagnetism controlled by the crystal anisotropy. Co2+ crystals with non‐linked tetrahedra show a dominant paramagnetic behavior irrespective of the organic spacer and the perovskite phase. This study demonstrates that the chemical flexibility of HOIPs can be exploited to develop novel layered magnetic materials with tailored magnetic properties. [ABSTRACT FROM AUTHOR]

In the article "Engineered Metal-Loaded Biohybrids to Promote the Attachment and Electron-Shuttling between Enzymes and Carbon Electrodes," Ana Beloqui and her colleagues discuss their research on cobalt-loaded protein biohybrids. These biohybrids can be easily deposited on carbon electrodes and exhibit excellent performance. The researchers demonstrate that these bioelectrodes can detect glucose without the need for external redox mediators, thanks to the cobalt-driven electron shuttling between the enzyme and the electrode. [Extracted from the article]

The article titled "The Interplay between Strain, Sn Content, and Temperature on Spatially Dependent Bandgap in Ge1-xSnx Microdisks" explores the mechanical and optical properties of germanium-tin microdisks. The researchers used finite element simulations and experimental techniques such as Raman and photoluminescence spectroscopy and nano-X-ray diffraction to study the emission properties of these microdisks. The findings highlight the correlation between the structural properties and the emission wavelength and spectral width of Ge1-xSnx microdisk lasers, emphasizing the importance of material-related considerations in the design of optoelectronic microstructures. [Extracted from the article]

Carbohydrate-rich byproducts may be used as a growth substrate for microalgae. The tiger nut, compared to other tubers, has higher carbohydrate content, which mostly remain in the byproduct after the production of tiger nut milk ("Horchata"). The aim of this study is the optimization of a hydrolysis pre-treatment in tiger nut byproduct to obtain reducing sugars, objective framed in the European SUSPUFA (Sustainable production of health-promoting n-3 LC-PUFA using agro-food industry by-products through microalgae) Project. Two experimental 4-factor Box–Behnken designs (acid concentration (N), temperature (°C), time (min) and ratio acid/sample) were carried out with 27 experiments to optimize chemical hydrolysis conditions with H2SO4 and H3PO4 in duplicate. The sugars were determined by the Schoorl method and the extracts obtained by the optimal conditions were analyzed by high-performance liquid chromatography (HPLC). Protected designation of origin (PDO) and non-protected designation of origin (n-PDO) tiger nut byproducts were characterized by physicochemical methods. The validity of the experimental designs was confirmed by ANOVA. The optimum sugar values were obtained with H2SO4 2 N at 85 °C, 60 min and ratio 60 and H3PO4 21 N at 90 °C, 60 min and ratio 60. Glucose and xylose were the sugars detected in the hydrolyzed samples. In conclusion, almost 50% of the total carbohydrates present in the tiger nut byproduct were hydrolyzed to reducing sugars. [ABSTRACT FROM AUTHOR]

Layered semiconductors of the IIIA–VIA group have attracted considerable attention in (opto)electronic applications thanks to their atomically thin structures and their thickness‐dependent optical and electronic properties, which promise ultrafast response and high sensitivity. In particular, 2D indium selenide (InSe) has emerged as a promising candidate for the realization of thin‐film field effect transistors and phototransistors due to its high intrinsic mobility (>102 cm2 V−1 s−1) and the direct optical transitions in an energy range suitable for visible and near‐infrared light detection. A key requirement for the exploitation of large‐scale (opto)electronic applications relies on the development of low‐cost and industrially relevant 2D material production processes, such as liquid phase exfoliation, combined with the availability of high‐throughput device fabrication methods. Here, a β polymorph of indium selenide (β‐InSe) is exfoliated in isopropanol and spray‐coated InSe‐based photodetectors are demonstrated, exhibiting high responsivity to visible light (maximum value of 274 A W−1 under blue excitation 455 nm) and fast response time (15 ms). The devices show a gate‐dependent conduction with an n‐channel transistor behavior. Overall, this study establishes that liquid phase exfoliated β‐InSe is a valid candidate for printed high‐performance photodetectors, which is critical for the development of industrial‐scale 2D material‐based optoelectronic devices. [ABSTRACT FROM AUTHOR]

Gallium selenide (GaSe) is a layered compound, which has been exploited in nonlinear optical applications and photodetectors due to its anisotropic structure and pseudodirect optical gap. Theoretical studies predict that its 2D form is a potential photocatalyst for water splitting reactions. Herein, the photoelectrochemical (PEC) characterization of GaSe nanoflakes (single‐/few‐layer flakes), produced via liquid phase exfoliation, for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) in both acidic and alkaline media is reported. In 0.5 m H2SO4, the GaSe photoelectrodes display the best PEC performance, corresponding to a ratiometric power‐saved metric for HER (Φsaved,HER) of 0.09% and a ratiometric power‐saved metric for OER (Φsaved,OER) of 0.25%. When used as PEC‐type photodetectors, GaSe photoelectrodes show a responsivity of ≈0.16 A W−1 upon 455 nm illumination at a light intensity of 63.5 µW cm−2 and applied potential of −0.3 V versus reversible hydrogen electrode (RHE). Stability tests of GaSe photodetectors demonstrated a durable operation over tens of cathodic linear sweep voltammetry scans in 0.5 m H2SO4 for HER. In contrast, degradation of photoelectrodes occurred in both alkaline and anodic operation due to the highly oxidizing environment and O2‐induced (photo)oxidation effects. The results provide new insight into the PEC properties of GaSe nanoflakes for their exploitation in photoelectrocatalysis, PEC‐type photodetectors, and (bio)sensors. [ABSTRACT FROM AUTHOR]

Solid-state fermentation can be an effective method of modelling the bioactive potential of plant materials, but the result is substrate and strain dependent. In this study, edible fungi traditionally used in Asian food fermentations (tempe moulds – Rhizopus oligosporus , R. oryzae and R. chinensis , koji mould – Aspergillus oryzae , oncom mould – Neurospora intermedia , and Mucor indicus) were grown on high-saponin quinoa seeds for 4 days at 30 °C. The sapogenin profile in the substrate was not changed after the fermentation. Whereas, the level and profile of phenolic compounds, as well as the antioxidant activity of the seeds, were diversified. The fermentation with R. chinensis , R. oryzae and A. oryzae caused an increase in soluble quercetin derivatives. Moreover, the concentration of bound phenolics was higher in the quinoa seeds fermented with most Rhizopus strains. The majority of the moulds were also efficient in the decomposition of phytate. Among the strains tested, the most promising results were obtained in the case of R. chinensis and R. oryzae. Further research is required to study their potential for the purpose of the fermentation of cereal and pseudocereal substrates. [Display omitted] • Fungal fermentation did not change the saponin profile in quinoa. • Fermentation with Rhizopus chinensis enriched quinoa seeds in total free phenolics. • Antioxidant activity was correlated with quercetin derivatives in fermented quinoa. • Quinoa fermentation with Rhizopus chinensis and R. oryzae gave the most promising results. [ABSTRACT FROM AUTHOR]

We developed a three-step colloidal synthesis of near-infrared (NIR) active Cu-In-Se (CISe)-based nanocrystals (NCs) via a sequential partial cation exchange realized in one pot. In the first step, binary highly copper deficient Cu2-xSe NCs were synthesized, followed by a partial cation exchange of copper to indium ions, yielding CISe NCs. This reaction allows for a precise control of the composition of the resulting NCs through a simple variation of the ratio between guest-cation precursors and parent NCs. To enhance the stability and the photoluminescence (PL) properties of the NCs, a subsequent ZnS shell was grown in the third step, resulting in CISeS/ZnS core/shell particles. These core/shell hetero-NCs exhibited a dramatic increase in size and a restructuring to trigonal pyramidal shape. The shell growth performed at a relatively high temperature (250 °C) also led to anion exchange, in which sulfur replaced part of selenium atoms close to the surface of the NCs, forming alloyed CISeS core structure. This efficient anion exchange is rarely reported for I-III-VI-based nanomaterials. Furthermore, we demonstrated that at higher reaction temperature, it is possible to obtain In-rich CISeS/ZnS NCs whose emission was shifted to the visible region. Therefore, a careful tuning of the reaction parameters, such as the Cu:Se and Cu:In ratios, temperature, and time, enables a distinct control over the size and composition of the NCs while maintaining their crystal structure. By varying the size of the CISeS/ZnS NCs from 9 to 18 nm, the PL spectra could be tuned, covering a wide NIR range with maxima from 990 to 1210 nm. Thus, in these experiments, we demonstrated a clear dependence of the optical properties of these materials on their size and extended the PL range of CISe-based NCs further to the infrared part of the spectrum. The results obtained might be important not only to elucidation of fundamentals of ion exchange reactions but also may provide a general preparative approach to a wide variety of copper chalcogenide-based NCs with well-controlled size, shape, composition, and even crystal structure. [ABSTRACT FROM AUTHOR]

In the past few years, several protocols have been reported on the synthesis of CdSe nanoplatelets with narrow photoluminescence (PL) spectrum, high PL quantum efficiency, and short exciton lifetime. The corresponding core/shell nanoplatelets are however still mostly based on CdSe/CdS, which possess an extended lifetime and a strong red shift of the band-edge absorption and emission, in accordance with a quasi-type-II band alignment. Here we report on a robust synthesis procedure to grow a ZnS shell around CdSe nanoplatelets at moderate temperatures of 100-150 °C, to improve the optical properties of CdSe nanoplatelets via a type-I core/shell heterostructure. The shell growth is performed under ambient atmosphere, in either toluene or 1,2-dichlorobenzene. The variation of the shell thickness induces a continuous red shift of the PL peak, eventually reaching 611 nm. The PL quantum efficiency is increased compared to the original CdSe cores, with values up to 60% depending on the shell thickness. High-resolution transmission electron microscopy reveals a bending of the nanoplatelets caused by strain due to 12% lattice mismatch between CdSe and ZnS. The present procedure can easily be translated to other core/shell nanocrystals, such as CdSe/CdS and CdSe/CdZnS nanoplatelets. [ABSTRACT FROM AUTHOR]

Two dimensional (2D) colloidal PbS nanoplatelets (NPLs) with a thickness of 1.8-2.8 nm have been synthesized using a single-molecule precursor approach with lead octadecylxanthate. The lateral dimensions were tuned by varying the reaction temperature, growth time, and capping ligands. Transmission electron microscopy and X-ray diffraction reveal that the NPLs have an orthorhombic crystal structure rather than the rocksalt phase usually reported for bulk and nanostructured PbS. The 1.8 nm thickness, in combination with the tunable lateral dimensions, results in a blue-shifted absorption peak at 715-730 nm and a 48-68 nm narrow emission spectrum with a surprisingly small, 18 nm Stokes shift at room temperature. The fluorescence lifetime of these PbS NPLs is 2 orders of magnitude shorter than the typical lifetime in 0D colloidal PbS quantum dots, highlighting the advantageous properties of colloidal 2D nanostructures that combine strong transversal with weak lateral confinement. [ABSTRACT FROM AUTHOR]

Colloidal core/shell nanocrystals are key materials for optoelectronics, enabling control over essential properties via precise engineering of the shape, thickness, and crystal structure of their shell. Here, the growth protocol for CdS branched nanocrystals is applied on CdSe nanoplatelet seeds and bone‐shaped heterostructures are obtained with a highly anisotropic shell. Surprisingly, the nanoplatelets withstand the high growth temperature of 350 °C and structures with a CdSe nanoplatelet core that is overcoated by a shell of cubic CdS are obtained, on top of which tetrahedral CdS structures with hexagonal lattice are formed. These complex core/shell nanocrystals show a band‐edge emission around 657 nm with a photoluminescence quantum yield of ≈42% in solution, which is also retained in thin films. Interestingly, the nanocrystals manifest simultaneous red and green emission and the relatively long wavelength of the green emission indicates charge recombination at the cubic/hexagonal interface of the CdS shell. The nanocrystal films show amplified spontaneous emission, random lasing, and distributed feedback lasing when the material is deposited on suitable gratings. This work stimulates the design and fabrication of more exotic core/shell heterostructures where charge carrier delocalization, dipole moment, and other optical and electrical properties can be engineered. [ABSTRACT FROM AUTHOR]

Directing and polarizing the emission of a fluorophore is of fundamental importance in the perspective of novel photonic sources based on emerging nanoemitter technologies. These two tasks are usually accomplished by a sophisticated and demanding structuring of the optical environment in which the emitter is immersed, or by nontrivial chemical engineering of its geometry and/or band structure. Here, the wavelength and polarization selective spontaneous emission from a dye‐embedded in a metal/insulator/metal (d‐MIM) nanocavity is demonstrated. A push–pull chromophore with large Stokes shift is embedded in a MIM cavity whose resonances are tuned with the spectral emission band of the chromophore. Angular and polarization resolved spectroscopy experiments reveal that the radiated field is reshaped according to the angular dispersion of the nanocavity, and that its spectrum manifests two bands with different polarization corresponding to the p‐ and s‐polarized resonances of the cavity. The d‐MIM cavities are a highly versatile system for polarization and wavelength division multiplexing applications at the nanoscale, as well as for near‐field focused emission and nanolenses. [ABSTRACT FROM AUTHOR]

Many studies have showed the beneficial effects of the olive (Olea europaea) leaf extract (OLE) in experimental models of metabolic syndrome, which have been ascribed to the presence of phenolic compounds, like oleuropeoside. This study evaluated the effects of a chemically characterized OLE in high fat diet (HFD)-induced obesity in mice, describing the underlying mechanisms involved in the beneficial effects, with special attention to vascular dysfunction and gut microbiota composition. C57BL/6J mice were distributed in different groups: control, control-treated, obese and obese-treated with OLE (1, 10 and 25 mg/kg/day). Control mice received a standard diet, whereas obese mice were fed HFD. The treatment was followed for 5 weeks, and animal body weight periodically assessed. At the end of the treatment, metabolic plasma analysis (including lipid profile) as well as glucose and insulin levels were performed. The HFD-induced inflammatory status was studied in liver and fat, by determining the RNA expression of different inflammatory mediators by qPCR; also, different markers of intestinal epithelial barrier function were determined in colonic tissue by qPCR. Additionally, flow cytometry of immune cells from adipose tissue, endothelial dysfunction in aortic rings as well as gut microbiota composition were evaluated. Faecal microbiota transplantation (FMT) to antibiotic-treated mice fed with HFD was performed. OLE administration reduced body weight gain, basal glycaemia and insulin resistance, and showed improvement in plasma lipid profile when compared with HFD-fed mice. The extract significantly ameliorated the HFD-induced altered expression of key adipogenic genes, like PPARs, adiponectin and leptin receptor, in adipose tissue. Furthermore, the extract reduced the RNA expression of Tnf-α , Il-1β , Il-6 in liver and adipose tissue, thus improving the tissue inflammatory status associated to obesity. The flow cytometry analysis in adipose tissue corroborated these observations. Additionally, the characterization of the colonic microbiota by sequencing showed that OLE administration was able to counteract the dysbiosis associated to obesity. The extract reversed the endothelial dysfunction observed in the aortic rings of obese mice. FMT from donors HFD-OLE to recipient mice fed an HFD prevented the development of obesity, glucose intolerance, insulin resistance and endothelial dysfunction. OLE exerts beneficial effects in HFD-induced obesity in mice, which was associated to an improvement in plasma and tissue metabolic profile, inflammatory status, gut microbiota composition and vascular dysfunction. [ABSTRACT FROM AUTHOR]

Marine compounds are a potential source of new anticancer drugs. In this study, the antiproliferative effects of 20 invertebrate marine extracts on three colon cancer cell models (HGUE-C-1, HT-29, and SW-480) were evaluated. Extracts from two nudibranchs (Phyllidia varicosa, NA and Dolabella auricularia, NB), a holothurian (Pseudocol ochirus violaceus, PS), and a soft coral (Carotalcyon sp., CR) were selected due to their potent cytotoxic capacities. The four marine extracts exhibited strong antiproliferative effects and induced cell cycle arrest at the G2/M transition, which evolved into early apoptosis in the case of the CR, NA, and NB extracts and necrotic cell death in the case of the PS extract. All the extracts induced, to some extent, intracellular ROS accumulation, mitochondrial depolarization, caspase activation, and DNA damage. The compositions of the four extracts were fully characterized via HPLC-ESI-TOF-MS analysis, which identified up to 98 compounds. We propose that, among the most abundant compounds identified in each extract, diterpenes, steroids, and sesqui- and seterterpenes (CR); cembranolides (PS); diterpenes, polyketides, and indole terpenes (NA); and porphyrin, drimenyl cyclohexanone, and polar steroids (NB) might be candidates for the observed activity. We postulate that reactive oxygen species (ROS) accumulation is responsible for the subsequent DNA damage, mitochondrial depolarization, and cell cycle arrest, ultimately inducing cell death by either apoptosis or necrosis. [ABSTRACT FROM AUTHOR]

The miniaturization of energy storage units is pivotal for the development of next‐generation portable electronic devices. Micro‐supercapacitors (MSCs) hold great potential to work as on‐chip micro‐power sources and energy storage units complementing batteries and energy harvester systems. Scalable production of supercapacitor materials with cost‐effective and high‐throughput processing methods is crucial for the widespread application of MSCs. Here, wet‐jet milling exfoliation of graphite is reported to scale up the production of graphene as a supercapacitor material. The formulation of aqueous/alcohol‐based graphene inks allows metal‐free, flexible MSCs to be screen‐printed. These MSCs exhibit areal capacitance (Careal) values up to 1.324 mF cm−2 (5.296 mF cm−2 for a single electrode), corresponding to an outstanding volumetric capacitance (Cvol) of 0.490 F cm−3 (1.961 F cm−3 for a single electrode). The screen‐printed MSCs can operate up to a power density above 20 mW cm−2 at an energy density of 0.064 µWh cm−2. The devices exhibit excellent cycling stability over charge–discharge cycling (10 000 cycles), bending cycling (100 cycles at a bending radius of 1 cm) and folding (up to angles of 180°). Moreover, ethylene vinyl acetate‐encapsulated MSCs retain their electrochemical properties after a home‐laundry cycle, providing waterproof and washable properties for prospective application in wearable electronics. Single‐/few‐layer graphene flakes, produced via scalable wet‐jet milling exfoliation of graphite, are used as the active material for micro‐supercapacitors (MSCs). The formulation of aqueous‐alcohol graphene inks, as well as the addition of carbon nanotubes, allows for the interdigitated structure to be screen‐printed on plastic substrates for metal‐free, flexible, solid‐state, and washable MSCs with high areal performance. [ABSTRACT FROM AUTHOR]