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In pursuit of developing alternatives for the highly polluting Haber–Bosch process for ammonia synthesis, the electrocatalytic nitrogen reduction reaction (NRR) using transition metal nitrides such as zirconium mononitride (ZrN) has been identified as a potential pathway for ammonia synthesis. In particular, specific facets of ZrN have been theoretically described as potentially active and selective for NRR. Major obstacles that need to be addressed include the synthesis of tailored catalyst materials that can activate the inert dinitrogen bond while suppressing hydrogen evolution reaction (HER) and not degrading during electrocatalysis. To tackle these challenges, a comprehensive understanding of the influence of the catalyst's structure, composition, and morphology on the NRR activity is required. This motivates the use of metal–organic chemical vapor deposition (MOCVD) as the material synthesis route as it enables catalyst nanoengineering by tailoring the process parameters. Herein, we report the fabrication of oriented and facetted crystalline ZrN thin films employing a single source precursor (SSP) MOCVD approach on silicon and glassy carbon (GC) substrates. First principles density functional theory (DFT) simulations elucidated the preferred decomposition pathway of SSP, whereas ab initio molecular dynamics simulations show that ZrN at room temperature undergoes surface oxidation with ambient O2, yielding a Zr–O–N film, which is consistent with compositional analysis using Rutherford backscattering spectrometry (RBS) in combination with nuclear reaction analysis (NRA) and X-ray photoelectron spectroscopy (XPS) depth profiling. Proof-of-principle electrochemical experiments demonstrated the applicability of the developed ZrN films on GC for NRR and qualitatively hint towards a possible activity for the electrochemical NRR in the sulfuric acid electrolyte. [ABSTRACT FROM AUTHOR]

Vapor phase infiltration (VPI) has emerged as a promising tool for fabrication of novel hybrid materials. In the field of polymeric gas separation membranes, a beneficial impact on stability and membrane performance is known for several polymers with differing functional groups. This study for the first time investigates VPI of trimethylaluminum (TMA) into poly(1‐trimethylsilyl‐1‐propyne) (PTMSP), featuring a carbon–carbon double bond as functional group. Saturation of the precursor inside the polymer is already attained after 60 s infiltration time leading to significant densification of the material. Depth profiling proves accumulation of aluminum in the polymer itself, but a significantly increased accumulation is visible in the gradient layer between polymer and SiO2 substrate. A reaction pathway is proposed and supplemented by density‐functional theory (DFT) calculations. Infrared spectra derived from both experiments and simulation support the presented reaction pathway. In terms of permeance, a favorable impact on selectivity is observed for infiltration times up to 1 s. Longer infiltration times yield greatly reduced permeance values close or even below the detection limit of the measurement device. The present results of this study set a strong basis for the application of VPI on polymers for gas‐barrier and membrane applications in the future. [ABSTRACT FROM AUTHOR]

In the conducted research study, solubility investigation was performed to elucidate the dissolution rate and behaviour of a drug incorporated within a solid dispersion matrix. The foremost objective was to appraise the impact of formulation parameters on the improvement of drug's solubility, the list of factors influencing the bioavailability. To this end, a systematic series of experiments were undertaken, wherein the drug was co-precipitated with a hydrophilic polymer carrier using various solvent systems and ratios. The resulting solid dispersions were meticulously characterized, employing state-ofthe-art analytical techniques. Subsequently, solubility profiles were generated through equilibrium solubility studies, encompassing a range of pH conditions and temperatures, to comprehensively evaluate the dissolution behaviour of the drug. Based on study, it was concluded that the solubility of Pazopanib Hydrochloride (Pazopanib base) is significantly increased from 0.001 mg/ml to ~8.000 mg/ml. the same was confirmed from the analytical tools. Analytical tools also confirm the conversion of crystalline form to amorphous form. The outcomes of these investigations provide essential insights into the potential utility of solid dispersion systems as a viable strategy for enhancing the solubility and, consequently, the therapeutic efficacy of the drug in question. [ABSTRACT FROM AUTHOR]

Energy dissipation through physical downscaling towards more complex types of memory and logic devices, loss of ultrapure water and consumption of large amounts of (toxic) chemicals for wafer cleaning processes, as well as high thermal budget of solid-state synthesis and thin film growth of standard semiconductors including the use of rare earth elements – all this poses great challenges for semiconductor materials science and technology. Therefore, research and development of alternative methods for micro- and nanofabrication and chemical functionalization of a new type of resource- and energy-efficient semiconductors as the core component of every computer chip is crucial. One of the promising opportunities is the transformation of today's complementary metal-oxide-semiconductor (CMOS) electronics into ecofriendly and neuroinspired electronics driven by molecular design and multi-level switching mechanisms at room temperature. The sustainable chemical technology of electron transport and switching materials in semiconductor manufacturing and the development of devices with new unconventional nanophysics, improved performance, and augmented functionalities (beyond-CMOS and More-than-Moore) is becoming increasingly important in the context of a gradual transition to a future-oriented concept of Internet of Everything (IoE). In this article, we focus on the technological significance of semiconductor preparation from single-source (molecular) precursors and the prospect of functionalizing semiconductors using DNA origami nanotechnology and stimuli-responsive metal–oxygen cluster ions such as polyoxometalates (POMs). We also describe the advanced characterization of these qualified molecular systems by soft X-rays. We emphasize the technical relevance of using solution-based methods for the bottom-up preparation of novel and hybrid semiconductors as well as their challenging scalability and the compatibility of methods of molecular technology with lithography-based mass production. Our article aims to contribute to the achievement of the United Nations' Sustainable Development Goal 9 (Industry, Innovation and Infrastructure). [ABSTRACT FROM AUTHOR]

The present study was aimed at analyzing uninfected wheat grain (Triticum aestivum) and wheat seed gall nematodes (Anguina titici) by means of wave-dispersive X-ray fluorescence (WD-XRF), Fourier transform infrared (FTIR) spectroscopy and Diffuse reflectance spectroscopy to assess their elemental and molecular compositions. WD-XRF was used to detect and quantify the major and trace elements in the tested samples. The minerals detected and quantified in no-infection, low infection and high infection wheat samples were potassium (K), sulphur (S), phosphorus (P), chlorine (Cl), calcium (Ca), magnesium (Mg), iron (Fe), silicon (Si), and zinc (Zn). Copper (Cu) was only observed in wheat samples showing no-infection and high infection. Chromium (Cr), manganese (Mn), and nickel (Ni) were detected only in wheat samples of low infection and high infection, and it was completely absent in uninfected wheat samples. Sodium (Na) was only detected in low infection samples whereas aluminium (Al) was only found in high infection wheat samples. The concentrations of these elements in different wheat samples varied. FTIR spectroscopy was used to study the molecular compositions of the infected and uninfected wheat grain samples. Diffuse reflectance measurements of uninfected and infected wheat samples were used to identify spectral differences among wheat samples. In the present investigation a detailed comparison of these samples has been presented at the elemental and molecular levels.

With a focus on Mn based organometallic compounds with suitable physico‐chemical properties to serve as precursors for chemical vapor deposition (CVD) and atomic layer deposition (ALD) of Mn‐containing materials, systematic synthetic approaches with ligand variation, detailed characterization, and theoretical input from density functional theory (DFT) studies are presented. A series of new homoleptic all‐nitrogen and mixed oxygen/nitrogen‐coordinated Mn(II) complexes bearing the acetamidinate, formamidinate, guanidinate and ß‐ketoiminate ligands have been successfully synthesized for the first time. The specific choice of these ligand classes with changes in structure and coordination sphere and side chain variations result in significant structural differences whereby mononuclear and dinuclear complexes are formed. This was supported by density functional theory (DFT) studies. The compounds were thoroughly characterized by single crystal X‐ray diffraction, magnetic measurements, mass spectrometry and elemental analysis. To evaluate their suitability as precursors for deposition of Mn‐based materials, the thermal properties were investigated in detail. Mn(II) complexes possessing the most promising thermal properties, namely Bis(N,N'‐ditertbutylformamidinato)manganese(II) (IV) and Bis(4‐(isopropylamino)pent‐3‐en‐2‐onato)manganese(II) (ßIII) were used in reactivity studies with DFT to explore their interaction with oxidizing co‐reactants such as oxygen and water which will guide future CVD and ALD process development. [ABSTRACT FROM AUTHOR]

Thin films of Al as interconnect materials and those of AlN as wide bandgap semiconductor and piezoelectric material are of great interest for microelectronic applications. For the fabrication of these thin films via chemical vapor deposition (CVD) based routes, the available precursor library is rather limited, mostly comprising aluminium alkyls, chlorides, and few small amine-stabilized aluminium hydrides. Herein, we focused on rational precursor development for Al, their characterization and comparison to existing precursors comprising stabilized aluminium hydrides. We present and compare a series of potentially new and reported aluminium hydride precursors divided into three main groups with respect to their stabilization motive, and their systematic structural variation to evaluate the physicochemical properties. All compounds were comprehensively characterized by means of nuclear magnetic resonance spectroscopy (NMR), Fourier-transform infrared spectroscopy (FTIR), elemental analysis (EA), electron-impact ionization mass spectrometry (EI-MS) and thermogravimetric analysis (TGA). Promising representatives were further evaluated as potential single source precursors for aluminium metal formation in proof-of-concept experiments. Structure and reaction enthalpies with NH3 or H2 as co-reactants were calculated via first principles density functional theory simulations and show the great potential as atomic layer deposition (ALD) precursors for Al and AlN thin films. [ABSTRACT FROM AUTHOR]

This feature article presents insights concerning the correlation of plasma‐enhanced chemical vapor deposition and plasma‐enhanced atomic layer deposition thin film structures with their barrier or membrane properties. While in principle similar precursor gases and processes can be applied, the adjustment of deposition parameters for different polymer substrates can lead to either an effective diffusion barrier or selective permeabilities. In both cases, the understanding of the film growth and the analysis of the pore size distribution and the pore surface chemistry is of utmost importance for the understanding of the related transport properties of small molecules. In this regard, the article presents both concepts of thin film engineering and analytical as well as theoretical approaches leading to a comprehensive description of the state of the art in this field. Perspectives of future relevant research in this area, exploiting the presented correlation of film structure and molecular transport properties, are presented. [ABSTRACT FROM AUTHOR]

A critical step in photocatalytic water dissociation is the hole‐mediated oxidation reaction. Molecular‐level insights into the mechanism of this complex reaction under realistic conditions with high temporal resolution are highly desirable. Here, we use femtosecond time‐resolved, surface‐specific vibrational sum frequency generation spectroscopy to study the photo‐induced reaction directly at the interface of the photocatalyst TiO2 in contact with liquid water at room temperature. Thanks to the inherent surface specificity of the spectroscopic method, we can follow the reaction of solely the interfacial water molecules directly at the interface at timescales on which the reaction takes place. Following the generation of holes at the surface immediately after photoexcitation of the catalyst with UV light, water dissociation occurs on a sub‐20 ps timescale. The reaction mechanism is similar at pH 3 and 11. In both cases, we observe the conversion of H2O into Ti−OH groups and the deprotonation of pre‐existing Ti−OH groups. This study provides unique experimental insights into the early steps of the photo‐induced dissociation processes at the photocatalyst‐water interface, relevant to the design of improved photocatalysts. [ABSTRACT FROM AUTHOR]

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This feature article presents recent results on the analysis of plasma/polymer interactions and the nucleation of ultra‐thin plasma films on polymeric substrates. Because of their high importance for the understanding of such processes, in situ analytical approaches of the plasma volume as well as the plasma/substrate interfaces are introduced before the findings on plasma surface chemistry. The plasma activation of polymeric substrates is divided into the understanding of fundamental processes on model substrates and the relevance of polymer surface complexity. Concerning thin film nucleation and growth, both plasma‐enhanced chemical vapor deposition and plasma‐enhanced atomic layer deposition processes as well as the combination of both processes are considered both for model substrates and technical polymers. Based on the comprehensive presentation of recent results, selective perspectives of this research field are discussed. [ABSTRACT FROM AUTHOR]

Nanocomposite systems based on iron(III) oxide (Fe2O3) and graphitic carbon nitride (gCN) possess a great potential as photo(electro)catalysts for environmental remediation and energy generation. In this field, a key issue is the fabrication of supported materials directly grown onto suitable substrates and possessing tailored features. In the present study, Fe2O3–gCN nanomaterials are prepared by an innovative two-step strategy, consisting of initial plasma assisted-chemical vapor deposition of iron(III) oxide on conducting glass substrates and subsequent functionalization with low amounts of gCN by a facile electrophoretic deposition process. Attention is dedicated to the use of two different forms of carbon nitride, obtained from melamine or melamine + cyanuric acid, in order to finely tune the resulting material composition. In this work, x-ray photoelectron spectroscopy was used to characterize the pristine Fe2O3 deposit as well as two Fe2O3–gCN composite materials prepared starting from different gCN powders. A detailed analysis of the obtained spectroscopic data reveals the occurrence of a direct electronic interplay between single constituents, dependent on material characteristics. The related results may act as useful guidelines for the design of photo(electro)catalysts endowed with specific properties, of importance for sustainable applications. [ABSTRACT FROM AUTHOR]

In the present study, the effects of oxygen plasma treatment and subsequent 2 nm thin Al2O3 film deposition by atomic layer deposition on about 30 nm thick hexamethyldisilazane polymer layers are investigated by using a combination of spectroscopic and electrochemical analysis. The investigations focus on the microporosity of the corresponding films and their structural changes. Upon oxygen plasma treatment, the surface near region of the films is converted into SiOx, and the microporosity is increased. Atomic layer deposition of Al2O3 on the plasma oxidized films leads to the decrease of pore sizes and an effective sealing. A correlation between the film microporosity and the change of hydroxyl groups of the films with the adsorption of water was established by ellipsometric porosimetry and in situ Fourier transform infrared (FTIR) spectroscopy. Moreover, electrochemical analysis provided complementary information on the electrolyte up‐take in the differently conditioned thin films. [ABSTRACT FROM AUTHOR]

To implement 2D molybdenum disulfide (MoS2) in the flexible electronic industry, large, uniform, and crystalline films on flexible substrates are needed. Thermal atomic layer deposition (ALD) generates large‐area uniform MoS2 films at low temperatures directly on temperature‐sensitive substrates. But if the grown films are amorphous, a high‐temperature posttreatment of the whole sample, which may cause thermal degradation of the substrate or other layers, needs to be avoided. In this article, the crystallization of amorphous MoS2 layers deposited by thermal ALD processed with picosecond laser pulses (λ = 532 nm), in a "cold" annealing process, is reported. The laser fluence range varies from Fmin$F_{\text{min}}$ = 8.73 mJ cm−2 to Fmax$F_{\text{max}}$ = 18.25 mJ cm−2 with scanning speeds from vscan,min$v_{\text{scan,min}}$ = 240 mm s−1 to vscan,max$v_{\text{scan,max}}$ = 2640 mm s−1. The crystallization and the influence of the processing parameters on the film morphology are analyzed in detail by Raman spectroscopy and scanning electron microscopy. Furthermore, a transition of amorphous MoS2 by laser annealing to self‐organized patterns is demonstrated and a possible process mechanism for the ultrashort‐pulsed (usp)‐laser annealing is discussed. Finally, the usp laser annealed films are compared to thermally and continuous‐wave‐laser‐annealed samples. [ABSTRACT FROM AUTHOR]

HfO2 thin films are appealing for microelectronic applications such as high‐κ dielectric layers, memristors, and ferroelectric memory devices. To fulfill the different requirements of each application, the properties of the deposited material need to be tuned accordingly. In this context, plasma‐enhanced atomic layer deposition (PEALD) is a powerful processing route to tailor the properties of HfO2 thin films, especially at low temperatures. Herein, a comprehensive bottom‐up approach is presented, ranging from the synthesis of molecularly engineered Hf precursors to the development of a HfO2 PEALD process and a detailed evaluation where plasma can be exploited to tune the dielectric properties. With the example of the newly synthesized bis‐(dialkylamido)‐bis‐(formamidinato) Hf(IV) precursor, [Hf{η2‐(iPrN)2CH}2(NMe2)2] which is reactive, thermally robust and volatile, successful implementation in a PEALD process for HfO2 at low temperatures is demonstrated. The typical atomic layer deposition (ALD) characteristics of precursor saturation, linearity, and ALD temperature window are demonstrated with constant growth of 0.7 Å per cycle from 125 to 200 °C, yielding high‐purity layers. The effect of plasma pulse duration on the chemical composition alongside structural, topographical, as well as dielectric properties of the films is investigated. For the latter, the films are incorporated in metal‐insulator semiconductor (MIS) structures. [ABSTRACT FROM AUTHOR]

Zirconia layers are often used as thermal barriers. In recent years, depositions by chemical vapor deposition methods using a metalorganic precursor (MOCVD) have been primarily investigated. Here, we combine MOCVD with plasma activation ‐ plasma‐enhanced chemical vapor deposition (PECVD]) ‐ of the gas phase and/or the growth surface to lower the growth temperature and to allow for a flexible coating design. PECVD causes the precursor to be transformed into a chemically active species, yielding thin films with a five times higher sticking coefficient compared to MOCVD. This leads to the onset of crystallization at lower surface temperatures. Carbon is incorporated at oxygen sites, so that the crystalline structure of zirconia is preserved, but the electrical conductivity is affected. The thermal conductivity is like that of pure zirconia. [ABSTRACT FROM AUTHOR]