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Abstract The removal of Ibuprofen was investigated by activated carbon impregnated with TiO 2. Emphasis was given on the effect of different parameters, such as composite type, initial Ibuprofen concentration (5–25 mg/L), temperature (22–28 °C) and pH (acidic and alkaline solution). The experiment was carried out in a self-made tubular flow reactor, with one 15 W monochromatic UV lamp (254 nm). The composite AC90T10 gives the highest removal degree of 92% of Ibuprofen solution under UV light within 4 h, due to synergy of adsorption and photodegradation. It was found that weight ratio of composite/Ibuprofen has limited effect on the removal degree within the concentration range (5–25 mg/L), but reaction time under UV light (4 h) and pH (acidic solution) are very important. The kinetic experimental data obtained at pH 4.3 at 25 °C on different composites were fitted to pseudo-first, pseudo-second and Elovich models, obtaining a high accuracy based on R2 values. From the results, composites of granular activated carbon and TiO 2 can enhance removal of Ibuprofen effectively, making recycle process much easier and less costly, which can be a promising method in future water treatment. Highlights • Three kinds of activated carbon impregnated with TiO 2 (ACT) were prepared. • Removal of Ibuprofen includes effects of adsorption and photodegradation by ACT. • ACT composites effectively improve removal of Ibuprofen under UV. • Kinetic tests of Ibuprofen removal were studied onto different composite catalysts. [ABSTRACT FROM AUTHOR]

Biopolymeric micro- and nanofibers with active ingredients have gained significant attention for biological applications. However, the incorporation of hydrophilic compounds into hydrophobic matrices via spinning techniques remain rather unexplored. Here we report the incorporation of dextran nanocapsules (Dex-NCs) in centrifugally spun poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx) fibers for the release of hydrophilic payloads. Inverse miniemulsion polymerization was employed to synthesize hydrophilic Dex-NCs with an average size of 0.25 µm. The Dex-NCs were embedded into PHBHHx via dual solvent centrifugal spinning at 0–7 wt% loading, resulting in beaded fibers with average fiber diameters of 4–6 µm. The effect of Dex-NC loading on the melting and crystallization behavior of PHBHHx was limited, while the strength and stiffness of the hybrid fibers was retained. The elongation of the hybrid fiber mats is reduced with increasing Dex-NC loading, but remains suitable for biological applications. Further, the in vitro release measurements showed a time dependent release of embedded Dex-NCs and the payload from the hybrid fibers. We anticipate this hybrid fiber matrix to be a starting point for the development of non-woven mats for slow release of hydrophilic payloads for biological applications, especially for medical wound dressings. [Display omitted] [ABSTRACT FROM AUTHOR]

Molecularly imprinted polymers (MIPs) can selectively bind target molecules and can therefore be advantageously used as a low-cost and robust alternative to replace fragile and expensive natural receptors. Yet, one major challenge in using MIPs for sensor development is the lack of simple and cost-effective techniques that allow firm fixation as well as controllable and consistent receptor material distribution on the sensor substrate. In this work, a convenient method is presented wherein microfluidic systems in conjunction with in situ photo-polymerization on functionalized diamond substrates are used. This novel strategy is simple, efficient, low-cost and less time consuming. Moreover, the approach ensures a tunable and consistent MIP material amount and distribution between different sensor substrates and thus a controllable active sensing surface. The obtained patterned MIP structures are successfully tested as a selective sensor platform to detect physiological concentrations of the hormone disruptor testosterone in buffer, urine and saliva using electrochemical impedance spectroscopy. The highest added testosterone concentration (500 nM) in buffer resulted in an impedance signal of 10.03 ± 0.19% and the lowest concentration (0.5 nM) led to a measurable signal of 1.8 ± 0.15% for the MIPs. With a detection limit of 0.5 nM, the MIP signals exhibited good linearity between a 0.5 nM and 20 nM concentration range. Apart from the excellent and selective recognition offered by these MIP structures, they are also stable during and after the dynamic sensor measurements. Additionally, the MIPs can be easily regenerated by a simple washing procedure and are successfully tested for their reusability. [ABSTRACT FROM AUTHOR]

Previous studies have shown that selective synthetic cell receptors can be produced by cell imprinting on polymer layers. However, knowledge on the fundamental detection mechanisms remains limited. In this article, while using yeast cells ( Saccharomyces cerevisiae ) as model cells, the factors influencing cellular recognition by surface-imprinted polymers (SIPs) are studied by means of spectroscopic and microscopy techniques and a transducer platform based on interfacial thermal transport, the so-called heat-transfer method (HTM). These analyses indicate that cell imprinting creates selective binding sites on the surface of the SIP layer in the form of binding cavities that match the cells in shape and size. Also, we show that phospholipid moieties are incorporated into the SIP cavities during imprinting, while membrane proteins do not seem to be transferred. More importantly, we demonstrate that the incorporated phospholipids significantly enhance cell adhesion to the SIP, and thus play a significant role in the cell-SIP binding mechanism. Furthermore, the hydrophobicity of the SIP layer was found to be considerably higher when compared with a non-imprinted polymer layer (NIP), an effect that could not be attributed to the presence of cavities on the surface of the SIP layer. Therefore, we suggest that the role of phospholipids in the SIP recognition mechanism is mediated by long range hydrophobic forces. [ABSTRACT FROM AUTHOR]

Weight reduction by omitting the use of bulky glass in c-Si photovoltaic (PV) modules is an important consideration of module development for vehicle-integrated photovoltaics (VIPV). Various approaches to achieve lightweight modules are proposed, yet there are many concerns regarding the reliability of such modules compared to standard glass-glass or glass-backsheet configurations. In this work, we investigate the thermo-mechanical behavior of LW modules with a multiwire design specifically aiming to VIPV applications. The developed modules consist of a commercially available carbon-fiber reinforced polypropylene backsheet and are compared to glass-fiber reinforced polypropylene backsheet modules. To enhance the thermo-mechanical reliability, polymer encapsulant and interconnection foil are substituted by glass-fiber reinforced composite encapsulant with the carbon-fiber reinforced polypropylene backsheet, thereby leading to ∼2.9% fill factor (FF) decrease with a limited degradation after 200 thermal cycles. A failure mechanism analysis using electroluminescence and X-ray-based micro-tomography is carried out after thermal cycling tests, clearly demonstrating that thermal stresses introduce deformation of wire interconnects. A modified high-temperature thermal cycling test (- 40 to 110 °C, 3.5 h) is implemented to observe the fast degradation of interconnects in compliance with VIPV conditions. The resulting fatigue stresses account for wire breakage in-between cells in the glass-fiber reinforced polypropylene module, while this effect is less pronounced in the carbon-fiber reinforced polypropylene backsheet module, indicating better thermo-mechanical reliability of the carbon-fiber reinforced polypropylene backsheet module. Herein, the current results could provide guidelines for lightweight PV module design (with a weight of 4.8 kg/m2) in the thermo-mechanical aspect. This research sheds light on the potential of lightweight modules specifically for VIPV applications. • Lightweight PV and novel interconnection are essential for VIPV applications. • CFPP backsheet enhances thermomechanical reliability over GFPP with 4.8 kg/m2. • Substituted encapsulant and interconnection foil with glass-fiber reinforced encapsulant. • Failure mechanism analysis carried out using EL and X-ray micro-tomography. • Wire interconnect failures are observed in GFPP modules. [ABSTRACT FROM AUTHOR]

The microwave assisted reaction between P25 titanium dioxide (TiO 2 ) and phenylphosphonic acid (PPA) is explored thoroughly and the influence of the reaction conditions on the grafting mechanism and formed products is presented. While the surface grafting is observed at low temperatures and water free conditions, the formation of titaniumphosphonate is favored in water and high reaction temperatures. For the first time the correlation between the amorphous TiO 2 phase and the formation of titaniumphenylphosphonate is reported. Materials are fully characterized by attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR), solid-state 31 P Nuclear Magnetic Resonance ( 31 P NMR) spectroscopy, energy dispersive X-ray (EDX) spectroscopy and transmission electron microscopy (TEM). [ABSTRACT FROM AUTHOR]

Hybrid materials are being developed to add organic functionalities to inorganic materials. Here, titanium dioxide is modified with organophosphonic acids (PAs). In several applications, the surface properties of the material play a key role in their performance (e.g. separation, sorption, catalysis). Hence, the surface properties of these materials need to be specifically adjusted to meet the requirements of each application (e.g. in membrane separation or chromatography). As the synthesis conditions have an important influence on the obtained surface properties, it is necessary to understand the impact and differences introduced by altering synthesis conditions. Different solvents are being applied for modification, but a comparative study of the impact of this change in environments is missing in literature. Therefore, our aim is to study the impact of concentration, temperature and pH in water and toluene on the properties of TiO 2 modified with propylphosphonic acid (3PA). By combining complementary techniques (DRIFT, TGA and 31 P/CP MAS NMR), clear differences induced by the solvent can be found. Moreover, in toluene a lower concentration of 3PA is required to obtain closed packed monolayers than in water. Furthermore, both solvent and concentration are influencing the modification degree and binding type formed on the surface. Moreover, only in water, next to the concentration, also the temperature and pH have a strong impact on the binding type of 3PA. A clear difference in thermal stability of 70 °C was found between both binding types. [ABSTRACT FROM AUTHOR]

Ternary organic photovoltaic devices were prepared through the addition of small amounts of metalloporphyin-terthiophenes to two established low bandgap polymer:fullerene blends. The methodology afforded a PCDTBT:PC 71 BM-based device that displayed an initial power conversion efficiency of 5.1%, an increase of 16% when compared to the binary blend. Among the range of metalloporphyrins considered in this study, the Cu(II)-porphyrin derivatives were found to result in the most significant efficiency improvements. [ABSTRACT FROM AUTHOR]

Hybrid titania phosphonate materials can demonstrate a high added value as tailored sorption materials. They combine high chemical stability with great structural versatility, given the wide diversity of functional groups that can be incorporated. Hereto, a fundamental understanding of the synthesis strategies influencing the material performance is required. Therefore three porous TiO 2 phosphonate hybrid structures with different functional groups (octyl, propyl, and phenyl) were evaluated in a solid-phase extraction application aimed towards solvent separation. The synthesis was performed by mixing bridged diphosphonic acids (DPAs) with Ti(OBu) 4 in a water-ethanol mixture at 30 °C, followed by a hydrothermal post-treatment at 120 °C. The materials were characterized by ICP-AES, 31P solid-state CP/MAS NMR, Raman and FTIR spectroscopy, X-ray diffraction, N 2 -sorption, and transmission electron microscopy. It is shown that the diphosphonic acids are quantitatively incorporated in the hybrid structures, leading to nanosized particles with a complex but uniquely functionalized surface. A study of the pore structure as a function of the incorporated DPA amount showed materials with a maximum BET surface area of 379 m2/g. The alkyl functionalized hybrid titania phosphonates demonstrated excellent and tunable sorption behavior. [Display omitted] • Porous Hybrid Titania phosphonates are hydrothermally prepared without template. • Incorporation of a diphosphonic acid group enhances porosity. • Material characteristics are heavily dependent on incorporation rate. • Solvent separation efficiency is highest for alkyl-modified materials. [ABSTRACT FROM AUTHOR]

Abstract: Detailed optimization of the device architecture of bulk heterojunction organic solar cells is of crucial importance when eventually targeting commercial applications. It has been shown before that the efficiency of such devices can be increased significantly upon incorporation of an imidazolium-substituted polythiophene interlayer. The cause of this increase in efficiency was, however, still unclear and is investigated here by a combination of PeakForce Quantitative Nanomechanical Mapping, PeakForce TUNA and Kelvin Probe Force Microscopy. A link between the local morphological and electrical properties is established. We show that the conjugated polyelectrolyte interlayer acts as a hole blocking layer. Additionally, illuminated Kelvin Probe Force Microscopy indicates that the interlayer creates an extra built-in electric field promoting charge transfer from the bulk heterojunction active layer into the interlayer. [Copyright &y& Elsevier]

Because of their intriguing properties for optoelectronic applications, research on organic semiconducting polymers has steadily progressed over the past decades, yielding increasingly fine-tuned (hetero)aromatic polymer backbones. In this work, the push-pull copolymer PDTPQx is synthesized, both via Stille polycondensation and direct arylation polymerization (DArP), permitting comparison of the two procedures. Near-infrared organic photodetectors (OPDs) are constructed based on these different polymer batches in combination with PC 61 BM, and their performance was investigated. From the current-voltage characteristics, it is clear that the DArP polymer-based devices outperform those prepared from the Stille polymers, both in terms of dark current density and external quantum efficiency (EQE), and therefore in terms of specific detectivity as well. The relatively high highest occupied molecular orbital energy level of PDTPQx, in combination with the clear charge-transfer absorption band observed for the DArP-based device, is beneficial for application in organic resonant cavity photodetectors. Such OPDs are prepared for the DArP PDTPQx:PC 61 BM (1:4) blends with 180 and 210 nm thick bulk heterojunction active layers. EQEs of 2.5% at 1016 nm and 1% at 1140 nm are achieved, with full-width-at-half-maximum peak responses of 44 and 45 nm, respectively, and detectivities of 2.24 × 1010 and 1.06 × 1010 Jones. [Display omitted] • Synthesis and characterization of a high-HOMO PDTPQx copolymer. • Comparison of Stille vs. direct arylation polymerization (DArP). • OPD (cavity) device fabrication, optimization and characterization. • Lowest dark current and highest detectivity for the DArP polymer. • D * values of 2.24 × 1010 Jones at 1016 nm and 1.06 × 1010 Jones at 1140 nm (FWHM ∼45 nm). [ABSTRACT FROM AUTHOR]

Abstract: Platinum (Pt) nanoparticles were successfully synthesized on tungsten oxide (WO3) thin films by electroless process without any further post-treatment. The prepared Pt nanoparticles were characterized by X-ray diffraction, X-ray photoelectron spectroscopy and field-emission scanning electron microscopy. Gas sensors based on the Pt–WO3 films were found to provide repeatable and significant responses to ppm-level H2. The size of Pt nanoparticles increases with the deposition time and has improved the sensing characteristics of the sensors. The work in this paper paves a facile way to the fabrication of Pt nanoparticles on metal oxide surface at a low temperature (68 °C). [Copyright &y& Elsevier]

Abstract: The introduction of functional moieties in the donor polymer (side chains) offers a potential pathway toward selective modification of the nanomorphology of conjugated polymer:fullerene active layer blends applied in bulk heterojunction organic photovoltaics, pursuing morphology control and solar cell stability. For this purpose, two types of poly(3-alkylthiophene) random copolymers, incorporating different amounts (10/30/50%) of ester-functionalized side chains, were efficiently synthesized using the Rieke method. The solar cell performance of the functionalized copolymers was evaluated and compared to the pristine P3HT:PCBM system. It was observed that the physicochemical and opto-electronic characteristics of the polythiophene donor material can be modified to a certain extent via copolymerization without (too much) jeopardizing the OPV efficiency, as far as the functionalized side chains are introduced in a moderate ratio (<30%) and that preference is given to side chains with a small molar volume. A range of complementary techniques – UV–Vis spectroscopy, (modulated temperature) differential scanning calorimetry, transmission electron microscopy and X-ray diffraction analysis – indicated that variations in polymer crystallinity, while maintaining a high level of regioregularity, are probably the main factor responsible for the observed differences. [Copyright &y& Elsevier]

Abstract: Thin aluminum nitride (AlN) films of different thickness are deposited by DC-pulsed magnetron sputtering under identical conditions on sapphire (0001) and silicon (100) substrates. An investigation of the residual stress, morphology and structural properties is carried out. The thickness of the films covers the range from 17nm to 3.9μm. A higher compressive residual stress is measured for the thinner films and the presence of a stress gradient is proven. X-ray diffraction (XRD) studies show that all AlN films are achieved with perfect c-axis orientation perpendicular to the film surface and that the films are biaxially strained. XRD rocking curves reveal that AlN films on sapphire are highly oriented for all film thicknesses, whereas AlN film growth on silicon starts highly disoriented and the film quality improves with film thickness. Surface analysis by atomic force microscopy shows a continuous film roughening and decrease of grain boundary density with increasing film thickness. [Copyright &y& Elsevier]

Abstract: Copper and zinc removal from water (pH = 5.0) using adsorbents produced from slow and fast pyrolysis of industrial sludge and industrial sludge mixed with a disposal filter cake (FC), post treated with HCl, is investigated in comparison with a commercial adsorbent F400. The results show that a pseudo-second order kinetics model is followed. The Langmuir–Freundlich isotherm model is found to fit the data best. The capacity for heavy metal removal of studied adsorbents is generally better than that of commercial F400. The dominant heavy metal removal mechanism is cation exchange. Higher heavy metal removal capacity is associated with fast pyrolysis adsorbents and sludge/FC derived adsorbents, due to enhanced cation exchange. Improvement of Zn2+ removal via 1 N HCl post-treatment is only effective when exchangeable cations of the adsorbent are substituted with H+ ions, which boost the cation exchange capacity. Increase of temperature also enhances metal removal capacity. Fast pyrolysis sludge-based adsorbents can be reused after several adsorption–desorption cycles. [Copyright &y& Elsevier]

Abstract: Within the field of organic bulk heterojunction solar cells, the morphology of the active layer has a key role in obtaining high power conversion efficiencies. P3HT nanofibers, obtained in highly concentrated solutions, are able to give controlled morphologies directly upon deposition. Since the solar cell efficiency of fiber solar cells depends on the fiber content of the casting solution, it is important to control this parameter. Here, we demonstrate an easy way to control the fiber content in the casting solution, i.e. changing the solution temperature. By using solution heating, the overall molecular weight of the polymer in the blend is kept constant, fiber isolation is not needed and the use of solvent mixtures is avoided. The obtained optimal power conversion efficiency is shown to be linked to the morphology of the active layer, which is studied with Transmission Electron Microscopy (TEM). [Copyright &y& Elsevier]

• Pre-calcination temperature/time define the organic residues in precursor powder. • Different amounts of organic residues lead to different particle sizes/morphology. • Pre-calcination at 200 °C for 40 h results in 1–4 µm powder of well-defined facets. • Electrochemical performance is improved using these pre-calcination conditions. [Display omitted] LiNi 0.5 Mn 1.5 O 4-δ (LNMO) is a potential candidate for high voltage Co-free cathodes in lithium-ion batteries. In this study, pre-calcination temperature, time, and oven type are showcased as important parameters influencing the particle size and morphology of the LNMO powder synthesized from the aqueous citric acid-acetates-NH 3 based method. These parameters determine the amount of organic residues in the precursor powder. A superior initial discharge capacity and capacity retention are obtained by an optimum combination of the particle size and morphology for the Li|LNMO coin cells. Pre-calcination in a forced convection oven at 200 °C for 40 h results in a voluminous and foam-like LNMO precursor powder morphology with the lowest amount of organic residue, leading to a ~ 1–4 µm powder with well-defined facets. Applying 24 h pre-calcination at 170 °C in a natural convection oven results in large LNMO aggregates of ~ 70 µm. Ball-milling of the crystalline LNMO powder is effective to reduce the agglomeration and particle size but deteriorates the electrochemical performance. An initial discharge capacity of 121 mA h g-1 at 0.2 C and a capacity retention of 90% after 400 cycles at 2 C are obtained from the samples prepared by 40 h pre-calcination at 200 °C in a forced-convection oven. [ABSTRACT FROM AUTHOR]

Abstract: In high performance polymer:fullerene bulk heterojunction solar cells the nanoscale morphology of interpenetrating acceptor:donor materials is optimized through appropriate preparation conditions such as annealing and choice of solvent, but this initial state-of-the-art morphology will not remain stable during long-term operation. We report the effects of prolonged storage at elevated temperatures on both the morphology and the photovoltaic performance for the model systems MDMO-PPV:PCBM and P3HT:PCBM as compared to ‘High T g PPV’:PCBM based solar cells, where the ‘High T g PPV’ is characterized by its high glass transition temperature (138°C). In situ monitoring of the photocurrent–voltage characteristics at elevated temperatures, in combination with a systematic transmission electron microscopy (TEM) study and complementary optical spectroscopy, reveals distinct degradation kinetics and morphological changes that indicate the occurrence of different underlying physico-chemical mechanisms. [Copyright &y& Elsevier]

Abstract: Three-dimensional (3D) self-assemblies of metal nanoparticles (NPs) are attracting intense attention for sensing applications since they display unique optical properties which are distinct from their respective bulk and individual NP characteristics. In this paper, 3D self-assembled gold (Au) NPs multilayer structures have been fabricated by the alternate deposition of a bifunctional cross-linker and Au NPs, to improve the refractive index sensitivity of the localized surface plasmon resonance sensor. UV–vis spectroscopy, atomic force microscopy (AFM) and cross-section transmission electron microscopy (TEM) have been used to characterize the obtained multilayer structures. The investigations show that the number of Au NP deposition cycles has a strong effect on the sensitivity of the sensor and the multilayer structure fabricated from four NP deposition cycles exhibits maximum sensitivity to the change of the environmental refractive index. [Copyright &y& Elsevier]

Two novel high gap donor polymers – PBDTTSi-TzBI and PBDTTS-TzBI , based on imide-fused benzotriazole (TzBI) with asymmetric side chains and alkylsilyl (Si) or alkylthio (S) substituted 4,8-di(thien-2-yl)benzo-[1,2- b :4,5- b ′]dithiophene (BDTT) – are successfully synthesized. The effect of the side chain variation on the photophysical, morphological and photovoltaic properties of blends of these polymers with fullerene and non-fullerene acceptors is investigated. The PBDTTSi-TzBI polymer shows a deeper highest occupied molecular orbital energy level, which results in higher open-circuit voltages. Nevertheless, the polymer solar cells fabricated using PBDTTS-TzBI in combination with PC 71 BM afford a higher power conversion efficiency of 7.3% (vs 4.0% for PBDTTSi-TzBI :PC 71 BM). By using the non-fullerene acceptor ITIC, the absorption of the blends extends to 850 nm and better device efficiencies are achieved, 6.9% and 9.6% for PBDTTSi-TzBI :ITIC and BDTTS-TzBI :ITIC, respectively. The better performance of the PBDTTS-TzBI :ITIC-based devices is attributed to the strong and broad absorption and balanced charge transport, and is among the best performances reported for non-fullerene solar cells based on TzBI-containing polymer donors. Image 1 • High gap copolymers based on benzodithiophene and imide fused benzotriazole are synthesized. • The polymers are applied in organic solar cells with both fullerene and non-fullerene acceptors. • Side chain variation (alkylthio vs -silyl) is used to optimize the active layer blend properties. • Alkylsilyl substitution leads to higher open-circuit voltages. • Power conversion efficiencies up to 9.6% are achieved under solar illumination. [ABSTRACT FROM AUTHOR]

The deployment of solid and quasi-solid electrolytes in lithium metal batteries is envisioned to push their energy densities to even higher levels, in addition to providing enhanced safety. This article discusses a set of hybrid solid composite electrolytes which combine functional properties with electrode compatibility and manufacturability. Their anodic stability >5 V versus Li + /Li and compatibility with lithium metal stem from the incorporated ionic liquid electrolyte, whereas the organic-inorganic hybrid host structure boosts their conductivity up to 2.7 mS cm -1 at room temperature. The absence of strong acids enables compatibility with porous NMC811 electrodes. Liquid precursor solutions can be readily impregnated into porous electrodes, facilitating cell assembly. Electrolytes containing TFSI - as the only anion have a superior compatibility toward high-voltage positive electrode materials, whereas electrolytes containing both FSI - and TFSI - have a better compatibility toward lithium metal. Using the former as catholyte and the latter as anolyte, NMC811/Li coin cells retain up to 100% of their initial capacity after 100 cycles (0.2 C, 3.0-4.4 V vs Li + /Li). Because of their unprecedented combination of functional properties, electrode compatibility, and manufacturability, these hybrid solid composite electrolytes are potential candidates for the further development of lithium metal battery technology., (© 2024 The Author(s). Advanced Science published by Wiley‐VCH GmbH.)

Lithium-rich, cobalt-free oxides are promising potential positive electrode materials for lithium-ion batteries because of their high energy density, lower cost, and reduced environmental and ethical concerns. However, their commercial breakthrough is hindered because of their subpar electrochemical stability. This work studies the effect of aluminum doping on Li 1.26 Ni 0.15 Mn 0.61 O 2 as a lithium-rich, cobalt-free layered oxide. Al doping suppresses voltage fade and improves the capacity retention from 46% for Li 1.26 Ni 0.15 Mn 0.61 O 2 to 67% for Li 1.26 Ni 0.15 Mn 0.56 Al 0.05 O 2 after 250 cycles at 0.2 C. The undoped material has a monoclinic Li 2 MnO 3 -type structure with spinel on the particle edges. In contrast, Al-doped materials (Li 1.26 Ni 0.15 Mn 0.61-x Al x O 2 ) consist of a more stable rhombohedral phase at the particle edges, with a monoclinic phase core. For this core-shell structure, the formation of Mn 3+ is suppressed along with the material's decomposition to a disordered spinel, and the amount of the rhombohedral phase content increases during galvanostatic cycling. Whereas previous studies generally provided qualitative insight into the degradation mechanisms during electrochemical cycling, this work provides quantitative information on the stabilizing effect of the rhombohedral shell in the doped sample. As such, this study provides fundamental insight into the mechanisms through which Al doping increases the electrochemical stability of lithium-rich cobalt-free layered oxides., (© 2024 Wiley‐VCH GmbH.)

Bio-based and biodegradable polyhydroxyalkanoates (PHAs) have great potential as sustainable packaging materials. The incorporation of zinc oxide nanoparticles (ZnO NPs) could further improve their functional properties by providing enhanced barrier and antimicrobial properties, although current literature lacks details on how the characteristics of ZnO influence the structure-property relationships in PHA/ZnO nanocomposites. Therefore, commercial ZnO NPs with different morphologies (rod-like, spherical) and silane surface modification are incorporated into poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx) via extrusion and compression molding. All ZnO NPs are homogeneously distributed in the PHBHHx matrix at 1, 3 and 5 wt.%, but finer dispersion is achieved with modified ZnO. No chemical interactions between ZnO and PHBHHx are observed due to a lack of hydroxyl groups on ZnO. The fabricated nanocomposite films retain the flexible properties of PHBHHx with minimal impact of ZnO NPs on crystallization kinetics and the degree of crystallinity (53 to 56%). The opacity gradually increases with ZnO loading, while remaining translucent up to 5 wt.% ZnO and providing an effective UV barrier. Improved oxygen barrier and antibacterial effects against S. aureus are dependent on the intrinsic characteristics of ZnO rather than its morphology. We conclude that PHBHHx retains its favorable processing properties while producing nanocomposite films that are suitable as flexible active packaging materials.

LNMO (LiNi 0.5 Mn 1.5 O 4- δ ) is a high-energy density positive electrode material for lithium ion batteries. Unfortunately, it suffers from capacity loss and impedance rise during cycling due to electrolyte oxidation and electrode/electrolyte interface instabilities at high operating voltages. Here, a solution-gel synthesis route was used to coat 0.5-2.5 μm LNMO particles with amorphous Li-Ti-O (LTO) for improved Li conduction, surface structural stability and cyclability. High-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) analysis coupled with energy dispersive X-ray (EDX) showed Ti-rich amorphous coatings/islands or Ti-rich spinel layers on many of the LTO-modified LNMO facets, with a thickness varying from about 1 to 10 nm. The surface modification in the form of amorphous islands was mostly possible on high-energy crystal facets. Physicochemical observations were used to propose a molecular mechanism for the surface modification, combining insights from metalorganic chemistry with the crystallographic properties of LNMO. The improvements in functional properties were investigated in half cells. The cell impedance increased faster for the bare LNMO compared to amorphous LTO modified LNMO, resulting in R ct values as high as 1247 Ω (after 1000 cycles) for bare LNMO, against 216 Ω for the modified material. At 10C, the modified material boosted a 15% increase in average discharge capacity. The improvements in electrochemical performance were attributed to the increase in electrochemically active surface area, as well as to improved HF-scavenging, resulting in the formation of protective byproducts, generating a more stable interface during prolonged cycling., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Volatile A-cation halide (AX) additives such as formamidinium chloride and methylammonium chloride have been widely employed for high-efficiency perovskite solar cells (PSCs). However, it remains unstudied how they influence the perovskite film stoichiometry and the solar cell performance and operational stability. Hereby, our work shows that over annealing of formamidinium chloride-containing perovskite films leads to a Pb-rich surface, resulting in a high initial efficiency, which however decays during maximum power point tracking (MPPT). On the contrary, perovskite films obtained by a shorter annealing time at the same temperature provide good stability during MPPT but a lower initial efficiency. Thus, we deduce that an optimal annealing is vital for both high efficiency and operational stability, which is then confirmed in the case where methylammonium chloride additive is used. With optimized perovskite annealing conditions, we demonstrate efficient and stable p-i-n PSCs that show a best power conversion efficiency of 20.7% and remain 90% of the initial performance after a 200 h MPPT at 60 °C under simulated 1 sun illumination with high UV content. Our work presents a comprehensive understanding on how volatile AX impacts perovskite film stoichiometry and its correlation to the device performance and operational stability, providing a new guideline for fabricating high-efficiency and operationally stable PSCs.

Driven by expanding interest in battery storage solutions and the success story of lithium-ion batteries, the research for the discovery and optimization of new battery materials and concepts is at peak. The generation of experimental (dis)charge data using coin cells is fast and feasible and proves to be a favorite practice in the battery research labs. The quantitative interpretation of the data, however, is not trivial and decelerates the process of screening and optimization of electrode materials and recipes. Here, we introduce the concept of polarographic map and demonstrate how it can be leveraged to quantify the contribution of different non-equilibrium phenomena to the performance limitation and total polarization of a lithium-ion cell. We showcase the accuracy and diagnostic power of this approach by preparing and analyzing the electrochemical performance of 54 sets of LiNi x Mn y Co 1-x-y O 2 electrodes with different formulations and designs discharged in a range of 0.2C-5C., Competing Interests: The authors declare that there is no conflict of interest., (© 2021 The Author(s).)

The large-scale use of the herbicide glyphosate leads to growing ecotoxicological and human health concerns. Microbe-assisted phytoremediation arises as a good option to remove, contain, or degrade glyphosate from soils and waterbodies, and thus avoid further spreading to non-target areas. To achieve this, availability of plant-colonizing, glyphosate-tolerant and -degrading strains is required and at the same time, it must be linked to plant-microorganism interaction studies focusing on a substantive ability to colonize the roots and degrade or transform the herbicide. In this work, we isolated bacteria from a chronically glyphosate-exposed site in Argentina, evaluated their glyphosate tolerance using the minimum inhibitory concentration assay, their in vitro degradation potential, their plant growth-promotion traits, and performed whole genome sequencing to gain insight into the application of a phytoremediation strategy to remediate glyphosate contaminated agronomic soils. Twenty-four soil and root-associated bacterial strains were isolated. Sixteen could grow using glyphosate as the sole source of phosphorous. As shown in MIC assay, some strains tolerated up to 10000 mg kg -1 of glyphosate. Most of them also demonstrated a diverse spectrum of in vitro plant growth-promotion traits, confirmed in their genome sequences. Two representative isolates were studied for their root colonization. An isolate of Ochrobactrum haematophilum exhibited different colonization patterns in the rhizoplane compared to an isolate of Rhizobium sp. Both strains were able to metabolize almost 50% of the original glyphosate concentration of 50 mg l -1 in 9 days. In a microcosms experiment with Lotus corniculatus L, O. haematophilum performed better than Rhizobium , with 97% of glyphosate transformed after 20 days. The results suggest that L. corniculatus in combination with to O. haematophilum can be adopted for phytoremediation of glyphosate on agricultural soils. An effective strategy is presented of linking the experimental data from the isolation of tolerant bacteria with performing plant-bacteria interaction tests to demonstrate positive effects on the removal of glyphosate from soils., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Massot, Gkorezis, Van Hamme, Marino, Trifunovic, Vukovic, d’Haen, Pintelon, Giulietti, Merini, Vangronsveld and Thijs.)

Cable bacteria are long, multicellular micro-organisms that are capable of transporting electrons from cell to cell along the longitudinal axis of their centimeter-long filaments. The conductive structures that mediate this long-distance electron transport are thought to be located in the cell envelope. Therefore, this study examines in detail the architecture of the cell envelope of cable bacterium filaments by combining different sample preparation methods (chemical fixation, resin-embedding, and cryo-fixation) with a portfolio of imaging techniques (scanning electron microscopy, transmission electron microscopy and tomography, focused ion beam scanning electron microscopy, and atomic force microscopy). We systematically imaged intact filaments with varying diameters. In addition, we investigated the periplasmic fiber sheath that remains after the cytoplasm and membranes were removed by chemical extraction. Based on these investigations, we present a quantitative structural model of a cable bacterium. Cable bacteria build their cell envelope by a parallel concatenation of ridge compartments that have a standard size. Larger diameter filaments simply incorporate more parallel ridge compartments. Each ridge compartment contains a ~50 nm diameter fiber in the periplasmic space. These fibers are continuous across cell-to-cell junctions, which display a conspicuous cartwheel structure that is likely made by invaginations of the outer cell membrane around the periplasmic fibers. The continuity of the periplasmic fibers across cells makes them a prime candidate for the sought-after electron conducting structure in cable bacteria.

Push-pull-type conjugated polymers applied in organic electronics do not always contain a perfect alternation of donor and acceptor building blocks. Misscouplings can occur, which have a noticeable effect on the device performance. In this work, the influence of homocoupling on the optoelectronic properties and photovoltaic performance of PDTSQx ff polymers is investigated, with a specific focus on the quinoxaline acceptor moieties. A homocoupled biquinoxaline segment is intentionally inserted in specific ratios during the polymerization. These homocoupled units cause a gradually blue-shifted absorption, while the highest occupied molecular orbital energy levels decrease only significantly upon the presence of 75-100% of homocouplings. Density functional theory calculations show that the homocoupled acceptor unit generates a twist in the polymer backbone, which leads to a decreased conjugation length and a reduced aggregation tendency. The virtually defect-free PDTSQx ff affords a solar cell efficiency of 5.4%, which only decreases substantially upon incorporating a homocoupling degree over 50%., (© 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A major conceptual breakthrough in cell signaling has been the finding of EV as new biomarker shuttles in body fluids. Now, one of the major challenges in using these nanometer-sized biological entities as diagnostic marker is the development of translational methodologies to profile them. SPR offers a promising label-free and real time platform with a high potential for biomarker detection. Therefore, we aimed to develop a uniform SPR methodology to detect specific surface markers on EV derived from patient with CHD. EVs having an approximate size range between 30 and 100 nm (~48.5%) and 100-300 nm (~51.5%) were successfully isolated. The biomarker profile of EV was verified using immunogold labeling, ELISA and SPR. Using SPR, we demonstrated an increased binding of EV derived from patients with CHD to anti-ICAM-1 antibodies as compared to EV from healthy donors. Our current findings open up novel opportunities for in-depth and label-free investigation of EV., (Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.)

Amylase and lysozyme are components of the salivary pellicle, exposing considerable enzymatic activity in the immobilized state. The purpose of the present study was to elucidate the influence of different solid substrata on the amount and distribution of amylase and lysozyme exposed on the surface of the salivary pellicle formed in situ. Slabs of titanium, feldspar ceramic, and bovine enamel were fixed on the buccal sites of individual splints worn by three subjects for 3 or 30 min, respectively, to allow pellicle formation. Subsequently, slabs were removed from the splints and rinsed with running water. Detection of amylase and lysozyme was performed by FEI-SEM after gold-immunolabeling of the enzymes. Both enzymes were found to be distributed randomly at the pellicle surface. Irrespective of formation time and substratum, significantly more labeled lysozyme molecules (5.23 +/- 4.5 microm(-2)) were detected compared with amylase (3.4 +/- 2.9 microm(-2)). Neither the substratum nor the pellicle formation time had significant impact on the amount of the respective enzyme that could be detected. This study for the first time provides evidence, that amylase and lysozyme are exposed at the surface of the salivary pellicle formed in situ on titanium and ceramics. Both enzymes are distributed randomly on the surface of the pellicle, irrespective of the underlying substratum.

We examined the subcellular cadmium (Cd) localization in roots and leaves of wild-type Arabidopsis thaliana (ecotype Columbia) exposed to environmentally relevant Cd concentrations. Energy-dispersive X-ray microanalysis (EDXMA) was performed on high-pressure frozen and freeze-substituted tissues. In the root cortex, Cd was associated with phosphorus (Cd/P) in the apoplast and sulfur (Cd/S) in the symplast, suggesting phosphate and phytochelatin sequestration, respectively. In the endodermis, sequestration of Cd/S was present as fine granular deposits in the vacuole and as large granular deposits in the cytoplasm. In the central cylinder, symplastic accumulation followed a distinct pattern illustrating the importance of passage cells for the uptake of Cd. In the apoplast, a shift of Cd/S granular deposits from the middle lamella towards the plasmalemma was observed. Large amounts of precipitated Cd in the phloem suggest retranslocation from the shoot. In leaves, Cd was detected in tracheids but not in the mesophyll tissue. Extensive symplastic and apoplastic sequestration in the root parenchyma combined with retranslocation via the phloem confirms the excluder strategy of Arabidopsis thaliana.