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Thin solid holmium titanium oxide films were grown by atomic layer deposition at 300 °C on silicon substrates. The precursors used were Ho(thd)3, Ti(OCH(CH3)2)4 and O3. The composition of the films was varied via changing the holmium-titanium ratio by variation of relative amounts of the sequential deposition cycles of constituent oxides, i.e. Ho2O3 and TiO2. The constituent oxides alone were crystallized in as-deposited states. After mixing the Ho2O3 or TiO2 layers the films were amorphous but were crystallized after annealing at 800-1000 °C, mostly transforming into the Ho2Ti2O7 phase. The stoichiometric ratio of 1:1 between Ti and Ho contents was achieved by application of at least twice as many Ho2O3 deposition cycles as TiO2 cycles. Magnetometry revealed that saturation magnetization could be observed in the films containing lower amounts of holmium compared to titanium. [ABSTRACT FROM AUTHOR]

Titanium dioxide nanotube arrays were anodised from titanium foils in an aqueous electrolyte solution of hydrofluoric acid. The formed oxide showed visually different colours owing to light interference in the titanium dioxide layer. The behaviour of interference colour in anodic titanium dioxide film was investigated by varying anodisation parameters such as the applied voltage and the anodisation time. The morphologies and the crystalline phases of anodised samples were studied on a field emission scanning electron microscope and X-ray diffractometer. The correlation between the interference colour and growth procedure of anodic titanium dioxide nanotube arrays was studied. The anodic films prepared under different conditions consisted of a compact oxide film with a nanoporous/tubular structure upon/beneath it. The crystalline phase of the anodic oxide layer was amorphous. The optical properties of the oxide film were investigated on a spectrophotometer. Optical interference could be detected in compact oxide layers when the thickness of the titanium dioxide was as small as 70 nm. In general, the interferences of the nanoporous/tubular structures were lower than those for compact structures. The empirical colour properties were estimated by the L* a* b* system. The relationships between the interference colour of anodic titanium dioxide film and its thickness and morphology are discussed. [ABSTRACT FROM AUTHOR]

Core WO3 nanofibers (140-300 nm in diameter, several hundred µm long) are made by a novel, water-based electrospinning process using ammonium metatungstate (AMT) and polyvinylpyrrolidone (PVP) as precursors. TiO2 shells (1.5-20 nm) are grown by atomic layer deposition (ALD) using TiCl4 and water at 250°C. The WO3/TiO2 composite fibers are analyzed using X-ray diffraction (XRD), scanning electron microscopy (SEM)-energy dispersive X-ray (EDX), transmission electron microscopy (TEM), Raman spectroscopy (RS), UV-Vis spectroscopy, and X-ray photoelectron spectroscopy (XPS). The optimal photocatalytic conversion under visible light is reached by the WO3/1.5 nm TiO2 nanofibers, which have higher activity compared to bare WO3 and Degussa TiO2. Thicker TiO2 layers fill the pores of the nanowires and reduce the specific surface area, weakening the photocatalytic activity. [ABSTRACT FROM AUTHOR]

Nanotubular titanium dioxide thin films were prepared by anodization of titanium metal films evaporated on indium tin oxide (ITO) coated glass. A facile method to enhance the adhesion of the titanium film to the ITO glass was developed. An optimum thickness of 550 nm for the evaporated titanium was found to keep the film adhered to ITO during the anodization. The films were further modified by growing amorphous titania, alumina and tantala thin films conformally in the nanotubes by atomic layer deposition (ALD). The optical, electrical and physical properties of the different structures were compared. It was shown that even 5 nm thin layers can modify the properties of the nanotubular titanium dioxide films. [ABSTRACT FROM AUTHOR]

The article shows that unsupported bulk gold (Au) itself can catalyze the liquid-phase oxidation of π-activated alcohols, such as benzyl alcohol (BA), cinnamyl alcohol (CA), into the corresponding aldehydes or ketones by oxygen (O2). BA, CA, 1-octanol, and 2-octanol were first selected to be oxidized over unsupported bulk Au foils. It was found that as the conversion increases, the selectivity to ester in BA oxidation in heptane increases.

This article demonstrates how important it is to find the optimal heating conditions when electrospun organic/inorganic composite fibers are annealed to get ceramic nanofibers in appropriate quality (crystal structure, composition, and morphology) and to avoid their disintegration. Polyvinylpyrrolidone [PVP, (CHNO)] and ammonium metatungstate [AMT, (NH)[HWO]· nHO] nanofibers were prepared by electrospinning aqueous solutions of PVP and AMT. The as-spun fibers and their annealing were characterized by TG/DTA-MS, XRD, SEM, Raman, and FTIR measurements. The 400-600 nm thick and tens of micrometer long PVP/AMT fibers decomposed thermally in air in four steps, and pure monoclinic WO nanofibers formed between 500 and 600 °C. When a too high heating rate and heating temperature (10 °C min, 600 °C) were used, the WO nanofibers completely disintegrated. At lower heating rate but too high temperature (1 °C min, 600 °C), the fibers broke into rods. If the heating rate was adequate, but the annealing temperature was too low (1 °C min, 500 °C), the nanofiber morphology was excellent, but the sample was less crystalline. When the optimal heating rate and temperature (1 °C min, 550 °C) were applied, WO nanofibers with excellent morphology (250 nm thick and tens of micrometer long nanofibers, which consisted of 20-80 nm particles) and crystallinity (monoclinic WO) were obtained. The FTIR and Raman measurements confirmed that with these heating parameters the organic matter was effectively removed from the nanofibers and monoclinic WO was present in a highly crystalline and ordered form. [ABSTRACT FROM AUTHOR]

Ru films were grown by atomic layer deposition in the temperature range of 275-350°C using (ethylcyclopentadienyl)(pyrrolyl)ruthenium and air or oxygen as precursors on HF-etched Si, SiO2, ZrO2, and TiN substrates. Conformal growth was examined on three-dimensional silicon substrates with 20:1 aspect ratio. ZrO2 promoted the nucleation of Ru most efficiently compared to other substrates, but the films roughened quickly on ZrO2 with increasing film thickness. The minimum number of cycles required to form continuous and conductive metal layers could be decreased by increasing the length of the oxygen pulse. In order to obtain well-conducting Ru films growth to thicknesses of at least 8-10 nm on any surface was necessary. Resistivities in the ranges of 30-60 and 14-16 μΩ·cm were achieved for 4-6 and 10-15 nm thick films, respectively. Delamination became an issue in the Ru films grown to thicknesses about 10 nm and higher. [ABSTRACT FROM AUTHOR]

Atomic layer deposition (ALD) of ZrO2-Gd2O3 nanolaminates and mixtures was investigated for the preparation of a high permittivity dielectric material. Variation in the relative number of ALD cycles for constituent oxides allowed one to obtain films with controlled composition. Pure ZrO2 films possessed monoclinic and higher permittivity cubic or tetragonal phases, whereas the inclusion of Gd2O3 resulted in the disappearance of the monoclinic phase. Changes in phase composition were accompanied with increased permittivity of mixtures and laminates with low Gd content. Further increase in the lower permittivity Gd2O3 content above 3.4 cat. % resulted in the decreased permittivity of the mixtures. Leakage currents generally decreased with increasing Gd content, whereby laminated structures demonstrated smaller leakage currents than mixed films at a comparable Gd content. Concerning the bottom electrode materials, the best results in terms of permittivity and leakage currents were achieved with Ru, allowing a capacitance equivalent oxide thickness of ~ 1 nm and a current density of 3 × 10-8 A/cm² at 1 V. Charge storage values up to 60 nC/mm² were obtained for mixtures and laminates with thickness below 30 nm. In general, at electric fields below 2-3 MV/cm, normal and trap-compensated Poole-Frenkel conduction mechanisms were competing, whereas at higher fields, Fowler-Nordheim and/or trap-assisted tunneling started to dominate. [ABSTRACT FROM AUTHOR]

Abstract: Through-porous steel fiber matrix with high specific surface area and self-support strength was examined as the support of TiO2 film photocatalyst. TiO2 was uniformly and conformally deposited onto the surface of the metal skeleton of the porous steel fiber matrix via atomic layer deposition method so that the porosity as well as gas permeability of the matrix is maintained. For further improving the photocatalytic activity, noble metals (Au and Pt/Pd alloy) were sputtered onto the surface of TiO2 photocatalyst. The photodegradation of methyl orange was used for evaluating the photocatalytic properties. The results show that compared with TiO2 films deposited on flat Si wafers, TiO2 films on the porous support display higher photocatalytic activities, owing to their higher specific surface areas. The photocatalytic activity of TiO2 on porous support was not enhanced by Au, while it was remarkably improved by Pt/Pd. The TiO2 photocatalysts were also analyzed by scanning electron microscopy and X-ray photoelectron spectroscopy. [Copyright &y& Elsevier]

Catalysis, Gold, Iodine, Recycling, Sustainable Chemistry Keywords: Catalysis; Gold; Iodine; Recycling; Sustainable Chemistry EN Catalysis Gold Iodine Recycling Sustainable Chemistry 1 1 1 03/23/22 20220328 NES 220328 B Gold b is a valuable metal that can be dissolved with common household chemicals as reported by Timo Repo et al. I i in their Research Article (e202117587). Inside Cover: Iodine-Catalysed Dissolution of Elemental Gold in Ethanol (Angew. [Extracted from the article]

Innentitelbild: Iodine-Catalysed Dissolution of Elemental Gold in Ethanol (Angew. Keywords: Catalysis; Gold; Iodine; Recycling; Sustainable Chemistry EN Catalysis Gold Iodine Recycling Sustainable Chemistry 1 1 1 03/23/22 20220328 NES 220328 B Gold b ist ein wertvolles Metall, das mit gewöhnlichen Haushaltschemikalien aufgelöst werden kann, wie Timo Repo et al. in ihrem Forschungsartikel (e202117587) berichten. Catalysis, Gold, Iodine, Recycling, Sustainable Chemistry. [Extracted from the article]

Abstract: Selective-area atomic layer deposition (ALD) was studied using microcontact printed self-assembled monolayers (SAM) as growth preventing mask layers. Patterned self-assembled octadecyltrichlorosilane (OTS, H3C(CH2)17SiCl3) monolayers were prepared on the silicon (100) surface by an elastomeric stamp which had 1.5 µm wide parallel print lines with 1.5 µm wide spaces in between. Passivation properties of the monolayers against ALD growth were verified by ALD processes of iridium and TiO2. Iridium was grown at 225 °C and TiO2 at 250 °C. The quality of SAM was controlled by water contact angle measurements. Patterned iridium and TiO2 films were studied with field emission scanning electron microscope and energy dispersive X-ray spectrometer. [Copyright &y& Elsevier]

Abstract: Al2O3 and TiO2 thin films were deposited by atomic layer deposition at 80–250°C on various polymeric substrates such as polymethylmethacrylate (PMMA), polyetheretherketone (PEEK), polytetrafluoroethylene (PTFE) and ethylenetetrafluoroethylene (ETFE). The films were studied with FESEM, EDX, XRD, contact angle measurements and adhesion tests. The film growth rates on the thermoplastics were close to the corresponding growth rates on Si substrates. The adhesion of the films was good on PEEK and poor on PTFE. All coated surfaces showed lower water contact angles than the uncoated thermoplastics. Furthermore, the water contact angles on all TiO2-coated surfaces decreased upon UV illumination, most efficiently with crystalline TiO2 coatings. [Copyright &y& Elsevier]

Iridium oxide thin films were grown with atomic layer deposition (ALD) from Ir(acac)3 and ozone between 165 and 200 °C. The films were successfully deposited on soda lime glass, silicon substrate with native oxide, and Al2O3 adhesion layer. Saturation of the growth rate with respect to both precursors was verified and the film thickness depended linearly on the number of deposition cycles applied. The iridium oxide films had low impurity contents and good adhesion to all tested surfaces. IrO2 film deposited at 185 °C had homogeneous depth profile and contained 3.5 at % hydrogen and less than 0.5 at % carbon impurities. Resistivities of about 40 nm thick IrO2 films varied between 170 and 200 µΩ cm. The films deposited above 200 °C were metallic iridium. All the films deposited were crystalline according to X-ray diffraction patterns. Iridium oxide films were grown between 165 and 200 °C. Saturation with respect to both Ir(acac)3 and ozone was achieved and the film thicknesses depended linearly on the number of deposition cycles applied. The films had low impurity contents and good adhesion to all tested surfaces. Resistivities were 170–200 µΩ cm for about 40 nm thick films deposited at 185 °C. [ABSTRACT FROM AUTHOR]

Abstract: In making and modifying nanomaterials conformality is a prerequisite for the thin film deposition method. From its principle ALD is an ideal method for coating nanomaterials. In this paper the use of ALD for making nanostructured materials is exemplified by many ways: making of nanolaminates, deposition of thin films inside nanopores, as well as coating of nanofibers and nanorods. The materials deposited by ALD are mostly oxides, nitrides and metals. [Copyright &y& Elsevier]

Gold is designated as the noblest metal because of its chemical inertness. It is known to dissolve in cyanide solutions in the presence of air or H2O2 or in halogen-containing solutions, aqua regia being the most famous example. Herein, we report a unique thiol, especially 4-pyridinethiol (4-PS), assisted dissolution of Au in alcohol solutions. Although dissolution was found to be very selective for pyridinethiols, such a phenomenon is astonishing since thiols are commonly used as etch resists for Au and even 4-PS is extensively used as a surface modifier for Au. To gain further understanding of the dissolution process, the influence of the reaction conditions was extensively studied. On the basis of the obtained results, a mechanism for the dissolution reaction is proposed. Fascinatingly, by tuning of the reaction conditions, this phenomenon can be applied in selective preparation of self-supporting nanometer-thick Au foils. [ABSTRACT FROM AUTHOR]

Abstract: High surface area Si/Al2O3/ZnO:Al capacitors were formed in electrochemically etched porous silicon. The Al2O3 dielectric and the ZnO:Al top electrode were deposited by atomic layer deposition in high aspect ratio porous Si. A single capacitor with a typical area of about 1mm2 consisted of about 105 pores. Effective capacitance densities were between 2.0 and 2.5μF/cm2, i.e., approximately 30 times higher than for a planar capacitor prepared under identical conditions, illustrating the effect of the enhanced surface area in the porous structure. [Copyright &y& Elsevier]

CuInSe 2 and its alloys with Ga and/or S are among the most promising absorber materials for thin film solar cells. CuInSe 2 -based solar cells have shown long-term stability and the highest conversion efficiencies of all thin film solar cells, above 19%. Solar cells based on these materials are also very stable, thus allowing long operational lifetimes. The preparation of a thin film solar cell is a multistage process where every step affects the resulting cell performance and the production cost. CuInSe 2 and other Cu chalcopyrites can be prepared by a variety of methods, ranging from physical vapor deposition methods such as evaporation and sputtering to low-temperature liquid phase methods such as electrodeposition. The present review discusses first the concept and operation principle of thin film solar cells, as well as the most important thin film solar cell materials. Next, the properties of CuInSe 2 and related compounds, as well as features of solar cells made thereof are reviewed. The last part of the text deals with deposition methods used for the preparation of CuInSe 2 and Cu(In,Ga)Se 2 thin film absorbers and solar cells. Although the emphasis here is on absorber preparation methods, buffer and conducting oxide preparation are discussed as well. [ABSTRACT FROM AUTHOR]

ZnO thin films doped with either In or Al were electrodeposited potentiostatically at 80 °C from aqueous solutions containing Zn(NO3)2 and either InCl3 or Al(NO3)3. The films were used for the preparation of pn-junctions based on electrodeposited CuInSe2 thin films. The pn-junctions were prepared both with and without the chemical bath deposited CdS interlayer, thus demonstrating the possibility to make all-electrodeposited pn-junctions for CuInSe2 thin film solar cells. [Copyright &y& Elsevier]

Δ EN T values were determined for 8 1-methyl-2-pyrrolidinone--solvent mixturesover the whole mole fraction range at 20, 30, and 50°C. The solvents used wereacetone, dimethyl sulfoxide, 2-propanol, 1,2-dichloroethane, water, 1,4-dioxane,benzyl alcohol, and hexamethylphosphoric triamide. The Δ EN T values werepositive for the NMP + solvent systems, except for the NMP + water system. [ABSTRACT FROM AUTHOR]

The unique structure of [2.2]paracyclophane (PCP) with its rigidity, stability, and planar chirality has gained significant attention in polymer and material research. In this work, the incorporation of amino‐functionalized PCPs within polymers of intrinsic microporosity (PIMs) is reported for the first time. Three different PCP‐PIMs were prepared via a Tröger's base formation mechanism, and their structures characterized via solid‐state NMR, MALDI‐TOF, and SEM. Their porosity was evaluated using gas adsorption (N2 and CO2) based on theoretical calculations such as Brunauer–Emmett–Teller (BET), NLDFT pore size distribution (PSD) and ideal IAST CO2/N2 selectivity (15/85), a crucial separation when considering the capture of CO2 from flue gas. The surface areas were found to be between 200–230 m2 g−1 while the selectivity for CO2/N2 ranged from 46 to 70. [ABSTRACT FROM AUTHOR]

Web-like architectures of ZnO and TiO2 nanotubes were fabricated based on a three-step process of templating polymer nanofibers produced by electrospinning (step 1). The electrospun polymer nanofibers were covered by radio-frequency magnetron sputtering with thin layers of semiconducting materials (step 2), with FESEM observations proving uniform deposits over their entire surface. ZnO or TiO2 nanotubes were obtained by subsequent calcination (step 3). XRD measurements proved that the nanotubes were of a single crystalline phase (wurtzite for ZnO and anatase for TiO2) and that no other crystalline phases appeared. No other elements were present in the composition of the nanotubes, confirmed by EDX measurements. Reflectance spectra and Tauc plots of Kubelka–Munk functions revealed that the band gaps of the nanotubes were lower than those of the bulk materials (3.05 eV for ZnO and 3.16 eV for TiO2). Photocatalytic performances for the degradation of Rhodamine B showed a large degradation efficiency, even for small quantities of nanotubes (0.5 mg/10 mL dye solution): ~55% for ZnO, and ~95% for TiO2. [ABSTRACT FROM AUTHOR]

Several aspects such as the growth relation between the layers of the GaN/AlN/SiC heterostructure, the consistency of the interfaces, and elemental diffusion are achieved by High Resolution Transmission Electron Microscopy (HR-TEM). In addition, the dislocation densities together with the defect correlation lengths are investigated via High-Resolution X-ray Diffraction (HR-XRD) and the characteristic positron diffusion length is achieved by Doppler Broadening Spectroscopy (DBS). Moreover, a comparative analysis with our previous work (i.e., GaN/AlN/Si and GaN/AlN/Al2O3) has been carried out. Within the epitaxial GaN layer defined by the relationship F 4 ¯ 3 m (111) 3C-SiC || P 63 m c (0002) AlN || P 63 m c (0002) GaN, the total dislocation density has been assessed as being 1.47 × 1010 cm−2. Compared with previously investigated heterostructures (on Si and Al2O3 substrates), the obtained dislocation correlation lengths (Le = 171 nm and Ls =288 nm) and the mean distance between two dislocations (rd = 82 nm) are higher. This reveals an improved crystal quality of the GaN with SiC as a growth template. In addition, the DBS measurements upheld the aforementioned results with a higher effective positron diffusion length L eff GaN 2 = 75 ± 20 nm for the GaN layer. [ABSTRACT FROM AUTHOR]

TiO2 thin films deposited by atomic layer deposition (ALD) at low temperatures (<100 °C) are, in general, amorphous and exhibit a smaller refractive index in comparison to their crystalline counterparts. Nonetheless, low-temperature ALD is needed when the substrates or templates are based on polymeric materials, as the deposition has to be performed below their glass transition or melting temperatures. This is the case for photonic crystals generated via ALD infiltration of self-assembled polystyrene templates. When heated up, crystal phase transformations take place in the thin films or photonic structures, and the accompanying volume reduction as well as the burn-out of residual impurities can lead to mechanical instability. The introduction of cation doping (e.g., Al or Nb) in bulk TiO2 parts is known to alter phase transitions and to stabilize crystalline phases. In this work, we have developed low-temperature ALD super-cycles to introduce Al2O3 into TiO2 thin films and photonic crystals. The aluminum oxide content was adjusted by varying the TiO2:Al2O3 internal loop ratio within the ALD super-cycle. Both thin films and inverse opal photonic crystal structures were subjected to thermal treatments ranging from 200 to 1200 °C and were characterized by in- and ex-situ X-ray diffraction, spectroscopic ellipsometry, and spectroscopic reflectance measurements. The results show that the introduction of alumina affects the crystallization and phase transition temperatures of titania as well as the optical properties of the inverse opal photonic crystals (iPhC). The thermal stability of the titania iPhCs was increased by the alumina introduction, maintaining their photonic bandgap even after heat treatment at 900 °C and outperforming the pure titania, with the best results being achieved with the super-cycles corresponding to an estimated alumina content of 26 wt.%. [ABSTRACT FROM AUTHOR]

Developing high performance, highly stable, and low-cost electrodes for the oxygen evolution reaction (OER) is challenging in water electrolysis technology. However, Ir- and Ru-based OER catalysts with high OER efficiency are difficult to commercialize as precious metal-based catalysts. Therefore, the study of OER catalysts, which are replaced by non-precious metals and have high activity and stability, are necessary. In this study, a copper–cobalt oxide nanosheet (CCO) electrode was synthesized by the electrodeposition of copper–cobalt hydroxide (CCOH) on Ni foam followed by annealing. The CCOH was annealed at various temperatures, and the structure changed to that of CCO at temperatures above 250 °C. In addition, it was observed that the nanosheets agglomerated when annealed at 300 °C. The CCO electrode annealed at 250 °C had a high surface area and efficient electron conduction pathways as a result of the direct growth on the Ni foam. Thus, the prepared CCO electrode exhibited enhanced OER activity (1.6 V at 261 mA/cm2) compared to those of CCOH (1.6 V at 144 mA/cm2), Co3O4 (1.6 V at 39 mA/cm2), and commercial IrO2 (1.6 V at 14 mA/cm2) electrodes. The optimized catalyst also showed high activity and stability under high pH conditions, demonstrating its potential as a low cost, highly efficient OER electrode material. [ABSTRACT FROM AUTHOR]

Coinage metals Cu, Ag, and Au are essential for modern electronics and their recycling from waste materials is becoming increasingly important to guarantee the security of their supply. Designing new sustainable and selective procedures that would substitute currently used processes is crucial. Here, we describe an unprecedented approach for the sequential dissolution of single metals from Cu, Ag, and Au mixtures using biomass‐derived ionic solvents and green oxidants. First, Cu can be selectively dissolved in the presence of Ag and Au with a choline chloride/urea/H2O2 mixture, followed by the dissolution of Ag in lactic acid/H2O2. Finally, the metallic Au, which is not soluble in either solution above, is dissolved in choline chloride/urea/Oxone. Subsequently, the metals were simply and quantitatively recovered from dissolutions, and the solvents were recycled and reused. The applicability of the developed approach was demonstrated by recovering metals from electronic waste substrates such as printed circuit boards, gold fingers, and solar panels. The dissolution reactions and selectivity were explored with different analytical techniques and DFT calculations. We anticipate our approach will pave a new way for the contemporary and sustainable recycling of multi‐metal waste substrates. [ABSTRACT FROM AUTHOR]

Pharmaceuticals, designed for treating diseases, ironically endanger humans and aquatic ecosystems as pollutants. Adsorption-based wastewater treatment could address this problem, however, creating efficient adsorbents remains a challenge. Recent efforts have shifted towards sustainable bio-based adsorbents. Here, cryogels from lignin-containing cellulose nanofibrils (LCNF) and lignin nanoparticles (LNPs) were explored as pharmaceuticals adsorbents. An enzyme-based approach using laccase was used for crosslinking instead of fossil-based chemical modification. The impact of laccase treatment on LNPs alone produced surface-crosslinked water-insoluble LNPs with preserved morphology and a hemicellulose-rich, water-soluble LNP fraction. The water-insoluble LNPs displayed a significant increase in adsorption capacity, up to 140 % and 400 % for neutral and cationic drugs, respectively. The crosslinked cryogel prepared by one-pot incubation of LNPs, LCNF and laccase showed significantly higher adsorption capacities for various pharmaceuticals in a multi-component system than pure LCNF or unmodified cryogels. The crosslinking minimized the leaching of LNPs in water, signifying enhanced binding between LNPs and LCNF. In real wastewater, the laccase-modified cryogel displayed 8–44 % removal for cationic pharmaceuticals. Overall, laccase treatment facilitated the production of bio-based adsorbents by improving the deposition of LNPs to LCNF. Finally, this work introduces a sustainable approach for engineering adsorbents, while aligning with global sustainability goals. [Display omitted] • Developing sustainable efficient adsorbents for pharmaceuticals remains challenging. • Nanocellulose and lignin nanoparticles were laccase-crosslinked to produce adsorbents. • The enzyme-based approach effectively anchored lignin nanoparticles onto nanocellulose. • Enzymatic crosslinking prevented the leaching of LNPs from the adsorbent. • Enzymatic crosslinking improved the removal of pharmaceuticals both from synthetic and real wastewater. [ABSTRACT FROM AUTHOR]

In article number 1806175, Nadia Passerini, Wei Li, Hélder A. Santos, and co‐workers report a nano‐inmicro composite for targeted therapy of inflammatory bowel disease via oral administration. The composite responds sequentially to pH and reactive oxygen species. The drug permeation through intestinal epithelium is also limited, providing a promising approach to limit unspecific absorption and systemic side effects. [ABSTRACT FROM AUTHOR]

Oxidative stress and abnormally high levels of reactive oxygen species (ROS) play an essential role in the pathogenesis and progression of inflammatory bowel disease (IBD). Oxidation‐responsive nanoparticles (NPs) are formulated from a phenylboronic esters‐modified dextran (OxiDEX) that degrades selectively in response to hydrogen peroxide (H2O2). OxiDEX NPs are coated with chitosan and encapsulated in a pH‐sensitive polymer to produce nano‐in‐micro composites. The microparticles are spherical with homogeneous particle size (53 ± 3 µm) and maintain integrity at acidic pH, preventing the premature release of the NPs in gastric conditions. The degradation of NPs is highly responsive to the level of H2O2, and the release of the drug is sustained in the presence of physiologically relevant H2O2 concentrations. The presence of chitosan on the particles surface significantly enhances NPs stability in intestinal pH and their adhesion on the intestinal mucosa. Compared to a traditional enteric formulation, this formulation shows tenfold decreased drug permeability across C2BBe1/HT29‐MTX cell monolayer, implying that lower amount of drug would be absorbed to the blood stream and, therefore, limiting the undesired systemic side effects. Based on these results, a successful nano‐in‐micro composite for targeted therapy of IBD is obtained by combination of the responsiveness to pH and ROS. An advanced nano‐in‐micro composite is successfully prepared with a phenylboronic esters‐modified dextran (OxiDEX) to achieve an oxidation‐responsive drug delivery for the therapy of inflammatory bowel disease. H2O2‐selective OxiDEX degradation and consequent drug release are demonstrated. The composite limits the drug permeation through intestinal epithelium providing a promising approach to limit unspecific absorption and systemic side effects. [ABSTRACT FROM AUTHOR]