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We report semitransparent NIR perovskite photodetectors based on tin–lead hybrid perovskites, by using very thin film perovskite layers and transparent indium tin oxide electrodes.

This paper analyses challenges and opportunities for improving energy efficiency in small and medium enterprises (SMEs) by reviewing research design and results out of seven European projects: SPEEDIER, SMEmPower Efficiency, E2Driver, Innoveas, Triple-A, DEESME and ICCEE. These projects aim to improve SMEs’ awareness of energy efficiency and support an effective decision-making-oriented approach to it. Drivers and barriers to energy efficiency improvements in European SMEs of various industrial sectors have been investigated by means of surveys, focused group discussions and interviews. A meta-analysis of the results of the seven EU projects was carried out to discover trends related to energy efficiency in European SMEs; this was supported by the use of a unifying analytic framework that enabled merging and cross-validation of the findings of the seven projects. The analysis indicated, by means of new data collected by the seven projects, that staff training, facilitation of energy audits, development of corporate policy measures and collaboration between SMEs involved in the same supply chain are key mechanisms to improve the uptake of energy efficiency measures in SMEs which has significant potential to achieve higher energy savings and energy cost reductions.

Perovskite/perovskite tandem solar cells have recently exceeded the record power conversion efficiency (PCE) of single-junction perovskite solar cells. They are typically built in the superstrate configuration, in which the device is illuminated from the substrate side. This limits the fabrication of the solar cell to transparent substrates, typically glass coated with a transparent conductive oxide (TCO), and adds constraints because the first subcell that is deposited on the substrate must contain the wide-bandgap perovskite. However, devices in the substrate configuration could potentially be fabricated on a large variety of opaque and inexpensive substrates, such as plastic and metal foils. Importantly, in the substrate configuration the narrow-bandgap subcell is deposited first, which allows for more freedom in the device design. In this work, we report perovskite/perovskite tandem solar cells fabricated in the substrate configuration. As the substrate we use TCO-coated glass on which a solution-processed narrow-bandgap perovskite solar cell is deposited. All of the other layers are then processed using vacuum sublimation, starting with the charge recombination layers, then the wide-bandgap perovskite subcell, and finishing with the transparent top TCO electrode. Proof-of-concept tandem solar cells show a maximum PCE of 20%, which is still moderate compared to those of best-in-class devices realized in the superstrate configuration yet higher than those of the corresponding single-junction devices in the substrate configuration. As both the top and bottom electrodes are semitransparent, these devices also have the potential to be used as bifacial tandem solar cells.

The deposition of transparent conductive oxides (TCO) usually employs harsh conditions that are frequently harmful to soft/organic underlayers. Herein, successful use of an industrial pulsed laser deposition (PLD) tool to directly deposit indium tin oxide (ITO) films on semitransparent vacuum-deposited perovskite solar cells without damage to the device stack is demonstrated. The morphological, electronic, and optical properties of the PLD deposited ITO films are optimized. A direct relation between the PLD chamber pressure and the solar cell performance is obtained. The semitransparent perovskite solar cells prepared exclusively by vacuum-assisted techniques had fill factors of 78% and exceeded 18% in power conversion efficiencies. This demonstrates that the direct deposition of TCO-based top electrodes without protective buffer layers is possible and leads to efficient devices.

Made available in DSpace on 2022-04-28T19:43:25Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-01-01 In the search for appropriate host matrices for highly luminescent molecular guest species, an organo-silica monolithic xerogel prepared by the hydrolysis and co-condensation reactions of 3-glycidoxypropyltrimethoxysilane (GPTS) and tetraethylorthosilicate (TEOS) is proposed. Such alkoxides allowed the development of hybrid silica monoliths with a cross-linked three-dimensional structure, in which the silica domains are strictly interconnected with the polymeric network. Highly luminescent monoliths were prepared from the immobilization of a blue-green emissive Ir(III) phosphor in the host matrix, with improved luminescent properties attributed to the greater rigidity of the medium and less diffusion of oxygen within the matrix. The structure of the hybrid material was elucidated by high-resolution solid-state NMR, confirming that the final structure of the developed silica matrix is very similar for both Ir(III)-doped and undoped xerogels. Altogether, the experimental strategy used in this work stands as an advance in the design of photo-functional materials with substantial potential for optical and photonic applications. [Figure not available: see fulltext.]. São Carlos Institute of Physics University of São Paulo, PO Box 369 Instituto de Ciencia Molecular (ICMol) Universidad de Valencia Department of Physics Institute of Geosciences and Exact Sciences Sao Paulo State University (UNESP) Department of Physics Institute of Geosciences and Exact Sciences Sao Paulo State University (UNESP)

Thin polymeric and small-molecular-weight organic semiconductors are widely employed as hole transport layers (HTLs) in perovskite solar cells. To ensure ohmic contact with the electrodes, the use of doping or additional high work function (WF) interlayer is common. In some cases, however, intrinsic organic semiconductors can be used without any additive or buffer layers, although their thickness must be tuned to ensure selective and ohmic hole transport. Herein, the characteristics of thin HTLs in vacuum-deposited perovskite solar cells are studied, and it is found that only very thin (= 5 nm), a dynamic behavior for consecutive electrical measurements is observed, a phenomenon which is also common to other widely used HTLs. Finally, it is found that despite their glass transition temperature, small-molecule HTLs lead to thermally unstable solar cells, asopposed to polymeric materials. The origin of the degradation is still not clear, but might be related to chemical reactions/diffusion at the HTL/perovskite interface, in detriment of the device stability

Vapor deposition of halide perovskites presents high potential for scalability and industrial processing of perovskite solar cells. It prevents the use of toxic solvents, allows thickness control, and yields conformal and uniform coating over large areas. However, the distinct volatility of the perovskite organic and inorganic components currently requires the use of multiple thermal sources or two-step deposition to achieve the perovskite phase. In this work, single-source, single-step MA1–xFAxPbI3 thin film deposition with tunable stoichiometry by pulsed laser deposition is demostrated. By controlling the laser ablation of a solid target containing adjustable MAI:FAI:PbI2 ratios, the room temperature formation of cubic α-phase MA1–xFAxPbI3 thin films is demonstrated. The target-to-film transfer of the ablated species, including the integrity of the organic molecules and the desired MA+:FA+ ratio, is confirmed by x-ray photoelectron spectroscopy and solid-state NMR. Photoluminescence analysis further confirms the shift of the bandgap with varying the MA+:FA+ ratio. Finally, proof-of-concept n-i-p solar cells with 14% efficiency are demonstrated with as-deposited non-passivated pulsed laser deposition (PLD)-MA1–xFAxPbI3. This study opens the path for future developments in industry-compatible vapor-deposition methods for perovskite solar cells.

Summary Transparent electrodes and metal contacts deposited by magnetron sputtering find applications in numerous state-of-the-art optoelectronic devices, such as solar cells and light-emitting diodes. However, the deposition of such thin films may damage underlying sensitive device layers due to plasma emission and particle impact. Inserting a buffer layer to shield against such damage is a common mitigation approach. We start this review by describing how sputtered transparent top electrodes have become archetypal for a broad range of optoelectronic devices and then discuss the possible detrimental consequences of sputter damage on device performance. Next, we review common buffer-layer materials in view of their processing-property-performance relationship. Finally, we discuss strategies to eliminate the buffer-layer requirement by implementing alternative, soft-landing deposition techniques for top electrodes. Our review highlights the critical issue of sputter damage for optoelectronic devices, formulates mitigation strategies, and provides cross-field learnings that can lead to more efficient and reliable optoelectronic devices aimed for commercialization.

Based on a circular bioeconomy strategy, eucalypt wood fines rejected from a Kraft pulp line were used as starting material in a pilot-scaled fast-pyrolysis process. The bio-oil and its coproducts were characterized regarding their physical, chemical, and thermal aspects. We put in perspective their properties to bring forward considerations for applications on biofuels, materials, and precursors. The yields of the pilot-scaled fast-pyrolysis process reached interesting values even if compared with optimized laboratory conditions. The results indicated the highest heating values (22–27 MJ/kg) for bio-oil, char, and crust material. The higher water content of aqueous extract had a negative effect for its application as fuel. The lignin/carbohydrate ratio for the bio-oil (2.82) and aqueous extract (0.53) identified a higher concentration of lignin-derived compounds in the first, mainly syringyl units. Bio-oil and aqueous extract presented chemical compounds with many functionalities, such as syringaldehyde and levoglucosan, expanding their potential application for higher value-added products besides energy.

Three molecular engineered [Ir(N^C)2(CF3pic)] complexes, where N^C are Fppy = 2-(2,4-difluorophenyl)pyridine, ppy = 2-phenylpyridine or Meppy = 2-(p-tolyl)pyridine, and CF3pic = 3-(trifluoromethyl)pyridine-2-carboxylate, are reported to elucidate their photophysical characteristics and emission profiles to emphasize rigidochromism. Their emission in fluid media is ascribed to a lowest-lying 3MLCT (metal-to-ligand charge transfer) excited state with emission quantum yields ( ϕ ) at room temperature of 0.13 for [Ir(Fppy)2(CF3pic)] and ϕ

Single layer light-emitting electrochemical cells (LECs) are amongst the simplest electroluminescent devices and operate with air-stable electrodes. Transparent light-emitting devices are of great interest as they can enable new applications in consumer electronics. In this work, a transparent ionic transition metal complex based LEC is fabricated by developing a transparent top contact based on tin (IV) oxide (SnO2) and indium-tin oxide, processed by low-temperature atomic layer deposition and pulsed laser deposition, respectively. The resulting devices present transparency in excess of 75% over the full visible spectrum (380-750 nm), with 82% transmission at the emission peak (563 nm). The devices emit from the front and the rear with high luminance (260 cd m−2) and long lifetime (176 h). These parameters place them among the highest performing single layer transparent electroluminescent devices.

The interaction between semiconductor materials and electromagnetic fields resonating in microcavities or the light-matter coupling is of both fundamental and practical significance for improving the performance of various photonic technologies. The demonstration of light-matter coupling effects in the emerging perovskite-based optoelectronic devices via optical pumping and electrical readout (e.g., photovoltaics) and vice versa (e.g., light-emitting diodes), however, is still scarce. Here, we demonstrate the microcavity formation in vacuum-deposited methylammonium lead iodide (CH3NH3PbI3, MAPI) p-i-n photovoltaic devices fabricated between two reflecting silver electrodes. We tune the position of the microcavity mode across MAPI's absorption edge and study the effect on the microcavity absorption enhancement. Tuning the microcavity mode toward lower energies enhances the absorption of the lower energy photons and steepens the absorption onset which reduces the effective optical gap (E-g) of the devices. This leads to a reduction in the open circuit voltage deficit. The research leading to these results has received funding from the Spanish Ministry of Science, Innovation and Universities (MICIU, RTI2018-095362-A-I00, PCI2019-111829-2, CEX2019-000919-M, and EQC2018-004888-P) and the Comunitat Valenciana (IDIFEDER/2018/061 and PROMETEU/2020/077). C.D. acknowledges that the project that gave rise to these results received the support of a fellowship from “la Caixa” Foundation (ID 100010434, code LCF/BQ/ DI19/11730020). M.S. acknowledges the MICIU for his RyC contract. A.P. acknowledges his Grisolia Grant from the Comunitat Valenciana GRISOLIAP/2020/134.

Stimuli responsive composites consisting of inorganic or organometallic coordination substrates supported on porous platforms that integrate and improve the key features of both the substrate and platform, open the doorway to advanced multifunctional materials. This work presents a new class of stimuli responsive multifunctional materials based on platinum(II) terpyridyl luminophores@silica composites. Presented here is how the intercalation of Pt(II) salts with a planar architecture and sterically permitting terpyridyl ligands within meso or microporous silica support impacts Pt(II) spectroscopies. The photophysics and luminescence properties of square-planar Pt(II) salts are dictated by their intermolecular, non-covalent Pt⋯Pt interactions between the individual Pt(II) units; a feature that has been explored in designing stimuli responsive materials. This work explores a novel methodology where the electronic structure and luminescence behavior of such salts are systematically varied through their intercalation within rigid silica frameworks. The intercalation of Pt(II) complexes with varied degrees of non-covalent Pt⋯Pt interactions in the virgin form within meso-macroporous silica supports generates materials that show marked variation in their electronic structure and luminescence behavior compared to their virgin salts. Further, the spectroscopies show a systematic dependance on the mean pore size of the silica support. The X-ray powder diffraction and microscopy studies reveal these behaviors to be related to the perturbations in their long-range structural order, that gets reflected in their microcrystalline dimensions and particle morphologies.

A versatile Ru(II) complex bearing an anthracene moiety was synthesized in our search for suitable compounds towards efficient molecular devices. The new engineered dye, cis‑[Ru(dcbH2)(NCS)2(mbpy‑anth)] (dcbH2 = 2,2′‑bipyridyl‑4,4′‑dicarboxylic acid, mbpy‑anth = 4‑[N‑(2‑anthryl)carbamoyl]‑4′‑methyl‑2,2′‑bipyridine), exhibits a blueish emission in a vibronically structured spectrum ascribed to the fluorescence of a 1LCAnth (ligand centered) excited state in the anthracene and has a potential to be exploited in the fields of smart lighting and displays. This complex was also employed in dye-sensitized solar cells with fairly efficient solar energy conversion with the use of self-assembled TiO2 compact layers beneath the TiO2 mesoporous film to prevent meso‑TiO2/dye back reactions. Further photoelectrochemical investigations through incident photon-to-current efficiency and electrochemical impedance spectra showed that the all-nano-TiO2 compact layer acts as contact layers that increase the electron harvesting in the external circuit, enhancing efficiencies up to 50%.

The photophysical dynamics of three complexes in the highly-emissive [Ir(pqi)2(NN)]+ series were investigated aiming at unique photophysical features and applications in light-emitting and singlet oxygen sensitizing research fields. Rational elucidation and Franck–Condon analyses of the observed emission spectra in nitrile solutions at 298 and 77 K reveal the true emissive nature of the lowest-lying triplet excited state (T1), consisting of a hybrid 3MLCT/LCIr(pqi)→pqi state. Emissive deactivations from T1 occur mainly by very intense, yellow-orange phosphorescence with high quantum yields and radiative rates. The emission nature experimentally verified is corroborated by theoretical calculations (TD-DFT), with T1 arising from a mixing of several transitions induced by the spin–orbit coupling, majorly ascribed to 3MLCT/LCIr(pqi)→pqi and increasing contributions of 3MLCT/LLCTIr(pqi)→NN. The microsecond-lived emission of T1 is rapidly quenched by molecular oxygen, with an efficient generation of singlet oxygen. Our findings show that the photophysics of [Ir(pqi)2(NN)][PF6] complexes is suitable for many applications, from the active layer of electroluminescent devices to photosensitizers for photodynamic therapy and theranostics.

Using the flexible ligand oxydiacetic acid (H2oda), ten new heteropolynuclear compounds with general formula [Ln2Zn3(oda)6]·xH2O (Ln = lanthanide ion, oda = oxydiacetate) were synthesized and structurally characterized. They were prepared by the direct reaction of oda in aqueous solution with stoichiometric amounts of Zn and Ln salts, followed by slow organic solvent diffusion. Two different structures were obtained: the larger lanthanides Pr, Nd, Eu and Tb gave compounds belonging to the hexagonal system, space group P6/mcc; whereas, the smaller ones, Ho, Er, Yb and Y formed cubic systems, space group Fdc. In the case of Dy, the two polymorphs were obtained by slight variations in the synthetic conditions. The phase change observed is discussed in comparison with previously reported [Ln2M3(oda)6]·xH2O compounds (M = bivalent metal ion). Luminescence studies were also carried out. Compounds containing Eu and Tb showed the most intense luminescence, also bearing relatively long lifetimes for the excited state deactivation. The luminescence profiles of both Dy systems are independent of the hexagonal or cubic arrangements, due to the similar environment of the Ln having the same point symmetry.

Sol–gel chemistry has been extensively employed to produce several classes of materials (e.g. nanoparticles, thin films, fibers, gels, glasses and ceramic powders) with desired easily-controllable morphological, crystallographic and mechanical properties. In particular, the methodology can be explored for the development of optical supramolecular materials with interesting properties for light-emitting devices, chemical and biological sensing, biomarking and targeting, among many others. To this end, the strategies usually adopted consist of embedding a luminescent guest species into normally non-emissive sol–gel host materials, resulting in optical systems that preserve both the guest's photophysical characteristics and the host's mechanical and morphological properties. This concise review provides insights into the development of promising new host–guest optical materials based on versatile sol–gel hosts (i.e. mesoporous MCM-41 nanoparticles, mesoporous sodium-aluminosilicate glasses and other mesoporous matrices for sensors) and highly luminescent guests (i.e. organic dyes, d6 complexes and lanthanide complexes), mostly focusing on the findings from our group and similar findings in the literature of the past decade.

The aim of this study is to enhance the use of agro-industrial byproducts and to address the environmental concerns by a novel method of co-production of thermoplastic composites with a solid residue constituting biorefinery. Accordingly, the reuse of 10–30 wt. % solid residues (SRH) from the enzymatic hydrolysis of recycled paper sludge (PS) in the production of thermoplastic composites with polypropylene (PP) was investigated. Thermal properties, water absorption, tensile strength and morphology of the prepared composites were evaluated. Higher thermal stability, rougher and wetter surface, and characteristics of a brittle material were observed in PP-SRH composites in comparison to the pristine PS-PP composites and the neat PP. The water absorption increased with increasing amount of SRH, but in lower proportion compared to other common raw materials used in the preparation of composites. Use of SRH resulted in similar or better properties compared to the composites made with the unhydrolyzed paper sludge, suggesting that SRH has potential for recycling and utilization as filler in the development of thermoplastic composites.

This review summarizes investigations carried out at the Laboratory of Photochemistry and Energy Conversion (LFCE) in the University of Sao Paulo dealing with design and characterization of ruthenium(II), rhenium(I) and iridium(III) polypyridine complexes with desired photochemical and photophysical properties in light of the development of optoelectronics and photoinduced energy conversion systems. First, the breakthroughs on molecular engineering of emissive ReI, RuII and IrIII complexes for the development of highly efficient light-emitting devices, such as organic light-emitting diodes (OLEDs) and light-emitting electrochemical cells (LECs), are presented. Then, the photochemical and photophysical properties of fac-[Re(CO)3(NN)(trans-L)]+ complexes (NN = bidentate polypyridyl ligands and trans-L = stilbene-like ligand), which find use in molecular machines and photosensors, are discussed. Finally, dye-sensitized energy conversion devices based on RuII complexes and natural dyes, such as dye-sensitized solar cells (DSCs) and dye-sensitized photoelectrosynthesis cells (DSPECs), are reviewed, highlighting some strategies for photoanode engineering aiming at improved device efficiencies.

Herein, the dehydration of a hydrogen molybdenum bronze (HYMoO3), converting it to molybdenum oxide (MoOX), is explored toward the development of perovskite solar cells (PSCs) for the first time. H0.11MoO3 bronze is synthesized, characterized, and deposited on indium tin oxide (ITO) under different concentrations and annealing conditions for in situ conversion into MoOX with appropriate oxygen vacancies. Vacuum‐deposited PSCs are fabricated using the as‐produced MoOX hole injection layers, achieving a power conversion efficiency of 17.3% (average) for the optimal device. The latter has its stability and reproducibility tested, proving the robustness and affordability of the developed hole transport layer in PSCs.

The increasing demand for electrical energy by a longer living and increasing population justifies the search for new, more efficient lighting systems. In this context, organo-metallic compounds have been largely investigated as efficient materials for organic light emitting diodes (OLEDs). Special interest has been demonstrated for neutral copper(I) complexes due to their high emission quantum efficiency and fast photoluminescence response time. In particular, Cu(I) complexes that present thermally activated delayed fluorescence (TADF) are one of the most promising materials for the next generation of lighting devices. In this work, we present an overview of the development of OLEDs, by comparing the mechanisms and efficiencies of different complexes and discussing the reasons why Cu(I) complexes have potential to be one of the most efficient alternatives for energy saving in lighting. Keywords: Light emitting devices, OLED, TADF, Cu(I) complexes

Hole transport layers HTLs are of fundamental importance in perovskite solar cells PSCs , as they must ensure an efficient and selective hole extraction, and ohmic charge transfer to the corresponding electrodes. In p i n solar cells, the ITO HTL is usually not ohmic, and an additional interlayer such as MoO3 is usually placed in between the two materials by vacuum sublimation. In this work, we evaluated the properties of the MoO3 TaTm TaTm is the HTL N4,N4,N4 amp; 8243;,N4 amp; 8243; tetra [1,1 amp; 8242; biphenyl] 4 yl [1,1 amp; 8242; 4 amp; 8242;,1 amp; 8243; terphenyl] 4,4 amp; 8243; diamine hole extraction interface by selectively annealing either MoO3 prior to the deposition of TaTm or the bilayer MoO3 TaTm without pre treatment on the MoO3 , at temperature ranging from 60 to 200 C. We then used these p contacts for the fabrication of a large batch of fully vacuum deposited PSCs, using methylammonium lead iodide as the active layer. We show that annealing the MoO3 TaTm bilayers at high temperature is crucial to obtain high rectification with low non radiative recombination, due to an increase of the electrode work function and the formation of an ohmic interface with TaTm

In our search for light powered molecular devices, a novel fac-[Re(CO)3(ph2phen)(trans-stpyCN)]+ complex was synthesized to show switchable trans-cis configurations of the coordinated stpyCN ligand through efficient and reversible photoassisted isomerizations. Controlled photolyses of acetonitrile solutions led to spectral changes ascribed to reversible trans⇌cis photoisomerization processes. A remarkable quantum yield for the back cis-to-trans isomerization was obtained, with the same magnitude of the trans-to-cis photoprocess, and curiously, both trans- and cis-isomers are emissive at room temperature. Photochemical and photophysical characterization studies for fac-[Re(CO)3(ph2phen)(stpyCN)]+ provided insights into the isomerization and emissive light-driven pathways that are resulted from the interactions between the close-lying intraligand and charge transfer states. The reversible cis-trans photoisomerization has potential to be exploited as light-powered molecular motors and geometry regulators in molecular machines.

With population growth and increasing industrialization, enormous amounts of agro-industrial wastes are being produced. Without proper use, these keep piling up leading to tremendous pressure on environmental safety. There is also considerable economic interest not only in the proper utilization of these wastes, but also in developing appropriate processes for this purpose. Sludge generated in pulp and paper mills is one of such solid wastes. Although several studies have investigated its reuse, it is still disposed mostly in landfills, leading to environmental pollution. Utilization of this waste could economically benefit for the pulp and paper sector. An innovative and potentially valuable solution seems to be converting it into ethanol, on which a considerable number of reports have published diverse reviews, even though improvements in the technology are still needed. Hence, this study attempts to provide an overview of all studies carried out so far, highlighting key scientific and technological barriers for scaling up and implementing the conversion process. Some suggestions for future research are given, while perspectives and projections point out that adoption of this process could be especially interesting for regions such as Europe and Asia, where the generation of sludge is high and the ethanol production capacity is still low.

Waste disposal from paper and pulp industry is of great environmental concern. Sludge from recycled paper mills favors colonization with different microbial species due to its chemical composition. In this environment, the microbiota can express enzymes that hydrolyze celluloses and hemicelluloses, such as cellulases, β-glucosidases, and xylanases. Understanding microbiota living in such disposal may give directions to what kind of enzymes or bioproducts may be possible to obtain from this microorganism and how to deal with the waste during the process. We have accessed microbial community associated with two steps in the recycled paper sludge generation by high-throughput DNA sequencing: fibrous residue, and wastewater sludge. Bacteroidetes, Proteobacteria and Firmicutes phyla represented more than 96% of the total. From the eukaryote perspective, Vorticella was the most frequent in fibrous residue samples while Acanthamoeba was the most common on wastewater sludge samples. Among the isolates cellulase activity was detectable only from fungi isolates. Half of the bacterial isolates presented xylanase activity, and most of them in high level of activity. Both a metabarcoding and culturing approaches are valuable tools for enzymatic screening in industrial waste disposal.

Zusammenfassung Ziel: Begrenzte Gesundheits- und Sprachkompetenz erschweren Menschen mit Migrationshintergrund (MmM) den Zugang zu Gesundheitsinformationen und -versorgung, gerade bei chronischer Krankheit. Bei der Einführung eines Peer-geleiteten Stanford Selbstmanagementkurses bei chronischer Krankheit wurde in der Schweiz großes Interesse und hohe Motivation von MmM beobachtet. Daher wurde eruiert, ob das Kursprogramm auf Deutsch bei moderaten Sprachkenntnissen umsetzbar ist. Methodik: Dies ist der explorative Teil der Begleitstudie zur Einführung des Stanford Programms in der Schweiz und im deutschsprachigen Europa. Angelehnt an Prinzipien der Grounded Theory wurden leitfadengestützte Fokusgruppen- und Einzelinterviews mit Kursteilnehmerinnen, -leiterinnen und -koordination (n=30) geführt, die thematisch ausgewertet wurden. Im Fokus der Datenerhebung standen die Durchführbarkeit, Zufriedenheit und Kursinhalte. Ergebnisse: Der Kurs stößt bei MmM auf positive Resonanz und scheint auf Deutsch prinzipiell durchführbar zu sein, hohe Alltagsrelevanz zu haben sowie Impulse zur Integration zu setzen. Schlussfolgerung: Zu prüfen ist ein weiterer Anpassungsbedarf auf den Migrationskontext, um den Kurs vulnerablen Gruppen besser zugänglich zu machen.

In the search for understanding and improving the luminescence of optical materials based on Ir(III) complexes, three [Ir(C∧N)2(dnbp)]+ (dnbp = 4,4′-dinonyl-2,2′-bipyridine) emitters were immobilized in MCM-41 mesoporous nanoparticles. By taking advantage of the amphiphilic nature of [Ir(C∧N)2(dnbp)]+, the complexes were mixed with an appropriate surfactant and the resulting micelles served as templates for the synthesis of mesoporous silica host materials in a one-step sol–gel route. The MCM-encapsulated [Ir(C∧N)2(dnbp)]+ complexes present intense emissions with prominent rigidochromic spectral changes that are substantially less affected by O2 as compared to methanolic solutions, with a thousand-fold decrease in quenching rate constants. These photophysical results points to a possible suitability of Ir(III)-complex–MCM-41 host–guest systems for possible future optoelectronic devices, rigidity optical sensors, or biological markers in different colors.

Vacuum-deposition of perovskite solar cells can achieve efficiencies rivalling solution-based methods and it allows for more complex device stacks. MoO3 has been used to enhance carrier extraction to the transparent bottom electrode in a p-i-n configuration, here we show that by inserting an organic charge transport molecule it can also be used on the top of a perovskite absorber in a n-i-p configuration. This strategy enables the first vacuum-deposited perovskite solar cells with metal oxides as charge transporting layers for both electrons and holes leading to power conversion efficiency > 19 %.

​This document is the Accepted Manuscript version of a Published Work that appeared in final form in ACS Applied Materials & Interfaces, copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see https://pubs.acs.org/doi/10.1021/acsami.9b04991, A variety of experiments on vacuum-deposited methylammonium lead iodide perovskite solar cells are presented, including JV curves with different scan rates, light intensity-dependent open-circuit voltage, impedance spectra, intensity-modulated photocurrent spectra, transient photocurrents, and transient voltage step responses. All these experimental data sets are successfully reproduced by a charge drift-diffusion simulation model incorporating mobile ions and charge traps using a single set of parameters. While previous modeling studies focused on a single experimental technique, we combine steady-state, transient, and frequency-domain simulations and measurements. Our study is an important step toward quantitative simulation of perovskite solar cells, leading to a deeper understanding of the physical effects in these materials. The analysis of the transient current upon voltage turn-on in the dark reveals that the charge injection properties of the interfaces are triggered by the accumulation of mobile ionic defects. We show that the current rise of voltage step experiments allow for conclusions about the recombination at the interface. Whether one or two mobile ionic species are used in the model has only a minor influence on the observed effects. A delayed current rise observed upon reversing the bias from +3 to -3 V in the dark cannot be reproduced yet by our drift-diffusion model. We speculate that a reversible chemical reaction of mobile ions with the contact material may be the cause of this effect, thus requiring a future model extension. A parameter variation is performed in order to understand the performance-limiting factors of the device under investigation.

In this work, efficient trans ⇌ cis photoswitchings of 4-(4-cyano)styrylpyridine (stpyCN) coordinated to organometallic bipyridyl tricarbonyl rhenium(I) complexes, fac-[Re(CO)

A new heteroleptic complex, [Ru(dcbH 2 )(bpy)(9AA)Cl] 2+ , Ru-9AA (9AA = 9-aminoacridine), was synthesized, characterized and used along with the previously synthesized [Ru(dcbH 2 )(bpy)(TCNE)Cl], Ru-TCNE (TCNE = tetracyanoethylene), in dye-sensitized solar cells (DSCs). The photoelectrochemical data were evaluated in comparison to the standard [Ru(dcbH 2 ) 2 (NCS) 2 ] dye, N3 . DSCs sensitized by these compounds exhibit overall efficiency conversion of 0.95 and 2.82% for Ru-9AA and Ru-TCNE , respectively, while that for N3 is 5.65% in the same condition. In spite of presenting lower global efficiencies than the standard dye, the Ru-TCNE complex present adequate electron injection efficiency and convert light into electricity effectively.

A microwave-assisted synthesis of novel N-acylhydrazone and semicacarbazone-7-hidroxy-coumarins derivatives, starting from 3-acetyl-7-hydroxy-2H-chromen-2-one, is described. This optimized protocol led to higher yields and considerable reduction in reaction time from ∼24 to ∼1 hour. Aqueous solutions of these compounds showed bright blue to cyan emission and maximum quantum yields of 0.244. The stereoelectronic effects of the attached groups led to modulation of the spectral characteristics by favoring syn or anti amide conformers. The synthesized compounds showed pH dependent luminescence and a strong batochromic shift up to 65 nm in a low polarity medium (methanol) due to a better stabilization of the syn-conformer promoting this redshifted emission. These characteristics can be exploited for designing new luminescent probes for pH as well as polar microenvironments.

Finding innovative solutions to manage waste and to expand the production of biofuels are some of the current challenges. Pulp and paper sectors, including recycled paper mills, produce a large amount of solid wastes, such as wastewater sludge containing non-recyclable short fibres. This study aimed to: (1) characterize recycled paper sludge; (2) define conditions for enzymatic hydrolysis and (3) evaluate two processes for ethanol production from the sludge: separate hydrolysis and fermentation (SHF) and simultaneous saccharification and fermentation (SSF). The waste showed a very high content of ash (58 %), which negatively affected enzyme action. A commercial enzyme cocktail (Cellic® CTec2) was used for the saccharification, at 43 °C and 6 % dosage. The highest ethanol yield (55.7 %) with shorter residence time (72 h) resulted from the SSF process. The best performance using the SHF process yielded 45.8 % after 84 h. Despite the intermediate results, sludge from pulp and paper mills could be an attractive raw material due to its low price and not requiring a pretreatment step for delignification. This application could be especially interesting for regions where the generation of paper sludge is high and the ethanol production capacity is still low, such as Asia.

The photophysical dynamics of three complexes in the highly-emissive [Ir(pqi)

In this work, efficient trans ⇌ cis photoswitchings of 4-(4-cyano)styrylpyridine (stpyCN) coordinated to organometallic bipyridyl tricarbonyl rhenium(I) complexes, fac-[Re(CO)3(NN)(trans-stpyCN)]+, where NN = 2,2′-bipyridine (bpy) or 4,4′-dimethyl-2,2′-bipyridine (dmb), are described. For both complexes, the true trans-to-cis quantum yields determined by 1H NMR spectroscopy are similar at 313, 334, and 365 nm irradiations (Φtrans→cistrue(313–365nm) ∼ 0.45), with a small decrease at 404 nm (Φtrans→cistrue(404nm) ∼ 0.37). The investigated complexes also exhibit significant quantum yields for the reversible cis-to-trans photoreactions (Φcis→trans(255nm) = 0.22). The luminescent properties of these complexes were also analyzed in different media to elucidate a key role of the 3ILstpyCN state in photophysical and photochemical processes, giving new insights on their intriguing photobehavior.

Cyclometalated IrIII complexes are promising candidates for biomedical applications but high cytotoxicity limits their use as imaging and sensing agents. We herein introduce the use of Laponite as carrier for triplet-emitting cyclometalated IrIII complexes. Laponite is a versatile nanoplatform because of its biocompatibility, dispersion stability and large surface area that readily adsorbs functional nonpolar and cationic molecules. These inorganic-organic hybrid nanomaterials mask cytotoxicity, show efficient cell uptake and increase luminescent properties and photostability. By camouflaging intrinsic cytotoxicity, this simple method potentially extends the palette of available imaging and sensing dyes to any metal-organic complexes, especially those that are usually cytotoxic.

A novel Ir(III) complex, [Ir(Fppy)2(Mepic)] (Fppy = 2-(2,4-difluorophenyl)pyridinate; Mepic = 3-methylpyridine-2-carboxylate) was engineered to show a blue phosphorescence with an impressive unitary quantum yield in our search for luminescent metal complexes for low cost displays and efficient lighting devices. Application of the Golden rule through Franck–Condon spectral analyses along with TD-DFT calculations and comparisons to the [Ir(Fppy)2(pic)] complex have provided insights on the mixing extension between charge-transfer (CT) and ligand-centered (LC) excited states in the emissive lowest-energy triplet transition for different media. The relatively narrow and vibronically-structured emission of [Ir(Fppy)2(Mepic)] at 298 K mainly arises from a spin–orbit-induced mixed 3MLCT-LCIr(Fppy)→Fppy/3LLCTFppy→Mepic excited state, with an enhanced MLCT character because of the methyl addition to pic. In frozen media at 77 K, the CT contribution is extinguished, leading to a pure LCFppy emission, with a similar emissive spectral profile to the free ligand, FppyH. The efficient blue emission shows that the complex is suitable for high-performance light-emitting devices and for thermo- and rigidity-sensors.

In our search for light powered molecular devices, a novel fac-[Re(CO)

This study was designed to appraise the relationship between enteric neuropathy and oxidative stress in cancer cachexia under l -glutamine-supplemented diet. Total and nitrergic neuronal populations were investigated in jejunum and ileum in four experimental groups: control (C); control l -glutamine-supplemented diet (CG); Walker-256 tumor (TW); and Walker-256 tumor supplemented with l -glutamine (TWG). In addition, local oxidative stress, neuronal nitric oxide synthase (nNOS) enzyme and nitric oxide (NO) levels were evaluated. Neuronal density and somatic area of the total and nitrergic populations were reduced in TW rats, which was accompanied by high oxidative stress, NO and nNOS levels. l -glutamine supplementation prevented neuronal atrophy, changes in pan neuronal density and nNOS overexpression (ileum), and restored total antioxidant capacity. Nevertheless, the oxidative stress was partially mitigated and no effect was observed on the reduction of nitrergic population and NO levels. l -glutamine-supplemented diet extenuates NO-mediated damage on the myenteric plexus although has a small benefit on oxidative stress.

An innovative all-nano-TiO2 thin film capable of enhancing dye-sensitized solar cell (DSC) photoefficiencies was prepared by a layer-by-layer method beneath the meso-TiO2 film, employing acid and basic nano-TiO2 sols as cations and anions, respectively. TiO2 syntheses were performed under absolute control to lead to appropriate morphological and optical properties to yield high-quality compact films using profilometry, tuning, and scanning electron microscopy. A detailed study by photoelectrochemical parameters, incident photon-to-current efficiency, electron lifetime, and electrochemical impedance spectroscopy demonstrates that the physical contact between FTO and the electrolyte is prevented and the role of the compact film has been elucidated. DSCs with TiO2 bilayers on top of FTO improved the conversion efficiency up to 62%, mainly because of the prevention of FTO/I3(-) charge recombination and an improved contact between FTO and TiO2.

Functional foods are one of new trends for the food industry and nanotechnology can be useful for enrichment of food or parts of the food with natural bioactive compounds. Besides the introduction of nutraceuticals into food, nanotechnology may allow the protection of the functional compounds against degradation, and, furthermore, improve their bioavailability. Nanocapsules of biomacromolecules can be employed for entrapment of sensitive hydrophobic nutraceuticals with partial protection against photochemical degradation to enrich food products without modifying sensory properties. Insoluble fibers from plants can be employed to improve intestinal tract and decrease cholesterol and sugar absorption into blood. Besides, nanoparticles or nanofibers would be useful for jellification or emulsions, which have great potential for beverage applications associated with delivery of bioactives. However, some nanomaterials, mainly inorganic crystalline ones, may have toxic effects in the body and proper steps should be taken before recommending them for industrial applications. There are many processes for obtaining nanomaterials, which may belong to either bottom-up and top-down approach. This chapter focuses on some of these aspects along with some perspectives.

In this work, mesoporous anatase submicrospheres, consisted of packed individual 6 nm nanocrystallites, were prepared by hydrolysis of titanium glycolate and compared with TiO 2 nanoparticles obtained by the hydrothermal method. The submicrometer spheres show an average diameter of 0.40 μm, while the TiO 2 nanoparticle diameter is 20 nm. Here, we developed a screen-printable submicrosphere paste to deposit bifunctional films with increased light scattering and higher dye uptake. In dye-sensitized solar cells, these films lead to a 32% increase in conversion efficiencies when compared to those with standard TiO 2 nanoparticles and can be even improved after TiCl 4 post-treatment.

In this work, extracts of mulberry (Morus alba L.), jaboticaba’s skin (Mirtus cauliflora Mart), java plum (Eugenia Jambolana Lam) and pomegranate (Punica Granatum) were used as solar cell sensitizers, exhibiting unique spectra due to intrinsic characteristics of each fruit. Natural-dye-sensitized solar cells showed improved photocurrents using pyridine-free, low-viscosity electrolytes. A nano-TiO2 compact layer was employed between the conducting glass (FTO) surface and the meso-TiO2 film aiming further efficiency enhancements to these DSCs sensitized by fruit extracts, leading to increased current densities and photon-to-current efficiencies along with improvements in open circuit potentials, dark currents and electron lifetimes. These results indicate that the compact layer is effective to improve the electron harvesting at the external circuit and to prevent the FTO/electrolyte electronic recombination, enhancing global efficiencies up to 66%.

Background and aims Three groups of subjects were identified within a representative sample of older Italians: subjects with normal fasting glucose (NFG), with impaired fasting glucose (IFG) or with type 2 diabetes mellitus (T2D). The aim of the present study was to evaluate the relationship among plasma lipids, lipoproteins, other metabolic factors in the three groups, and their role in predicting total fatal events. Methods and results 2422 subjects, aged 65–84 years, taking part into the Italian Longitudinal Study on Aging were included in the analyses. Factor analysis was conducted separately for men and women. Factor scores were used as independent variables in Cox Proportional Hazard models, to determine factors predicting death at the follow-up in NFG, IFG and T2D subjects. Four major factors were found for men (“insulin resistance”, “body size”, “total cholesterol”, “HDL cholesterol”) and four also for women (“insulin resistance”, “total cholesterol”, “body size”, “HDL cholesterol”). For NFG and IFG men, and for both T2D men and women, the “HDL cholesterol” was a significant protective factor for total deaths (NFG men: HR = 0.79, 95% CI 0.67–0.93; IFG men: HR = 0.59, 95% CI 0.45–0.79; T2D men: HR = 0.55, 95% CI 0.34–0.89; T2D women: HR = 0.61, 95% CI 0.44–0.86). Among NFG women, the “body size” factor was also a protective factor with respect to total deaths (HR = 0.74, 95% CI 0.57–0.95). Conclusion A factor including HDL Cholesterol and Apo A-I showed protection against all-cause mortality in older men, independently from the glycemia level, and in women only in those diagnosed with T2D.