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Three Lewis acid–base adducts t‐Bu3Ga–EPh3 (E = P 1, As 2, Sb 3) were synthesized by reactions of Ph3E and t‐Bu3Ga and characterized by heteronuclear NMR (1H, 13C (31P)) and IR spectroscopy, elemental analysis and single crystal X‐ray diffraction. Their structural parameters are discussed and compared to similar t‐Bu3Ga adducts. The strength of the donor‐acceptor interactions within 1–3 was investigated in solution by temperature‐dependent 1H NMR spectroscopy and by quantum chemical calculations. [ABSTRACT FROM AUTHOR]

Crystalline Sb2Se3 nanoparticles were prepared by reaction of SbCl3 with (Et3Si)2Se in the presence of oleylamine (OA) in the ionic liquid [C4C1Im]Cl, whereas the reaction of (Et3Si)2Se with [C4C1Im]3[BiCl6] ( 1), which was obtained from the reaction of BiCl3 with [C4C1Im]Cl and structurally characterized by single-crystal X-ray diffraction, yielded Bi-rich Bi2Se3 nanoparticles. In contrast, the reaction of the reactive IL [C4C1Im]3[Bi3I12] with (Et3Si)2Se in the presence of oleylamine in [C4C1Im]I gave phase-pure Bi2Se3 nanoparticles. The chemical composition of the nanoparticles was investigated by EDX, while possible surface contaminations were studied by XPS and IR spectroscopy. The morphology of the nanoparticles was studied by SEM and TEM. [ABSTRACT FROM AUTHOR]

Crystalline Sb2Se3 nanoparticles were prepared by reaction of SbCl3 with (Et3Si)2Se in the presence of oleylamine (OA) in the ionic liquid [C4C1Im]Cl, whereas the reaction of (Et3Si)2Se with [C4C1Im]3[BiCl6] ( 1), which was obtained from the reaction of BiCl3 with [C4C1Im]Cl and structurally characterized by single-crystal X-ray diffraction, yielded Bi-rich Bi2Se3 nanoparticles. In contrast, the reaction of the reactive IL [C4C1Im]3[Bi3I12] with (Et3Si)2Se in the presence of oleylamine in [C4C1Im]I gave phase-pure Bi2Se3 nanoparticles. The chemical composition of the nanoparticles was investigated by EDX, while possible surface contaminations were studied by XPS and IR spectroscopy. The morphology of the nanoparticles was studied by SEM and TEM. [ABSTRACT FROM AUTHOR]

Intramolecularly stabilized Sb(OCH2CH2NMe2)3 ( 1) and Bi(OCH2CH2NMe2)3 ( 2) readily react with (Me3Si)2S and (Et3Si)2E (E = Se, Te) at moderate temperatures (hot injection method) with elimination of the corresponding silyl ether and subsequent formation of the group 15 chalcogenides Sb2E3 and Bi2E3, which were characterized by XRD, SEM, and energy-dispersive X-ray spectroscopy (EDX). In addition, the solid-state structure of 1 was determined by single-crystal XRD. [ABSTRACT FROM AUTHOR]

Layered Sb[sub 2]Te[sub 3] films were grown by a MOCVD process on Al[sub 2]O[sub 3](0001) substrates at 400 °C by use of i-Pr[sub 3]Sb and Et[sub 2]Te[sub 2] and characterized by SEM, AFM, XRD, EDX and Auger spectroscopy. The electrical sheet resistivity was measured in the range of 4 to 400 K, showing a monotonic increase with increasing temperature. The valence band structure probed by angle-resolved photoemission shows the detailed dispersions of the bulk valence band and the topological surface state of a quality no less than for optimized bulk single crystals. The surface state dispersion gives a Dirac point roughly 30 meV above the Fermi level leading to hole doping and the presence of bulk valence states at the Fermi energy. [ABSTRACT FROM AUTHOR]

Crystalline Ga2O3 nanowires are synthesized via an Au-catalyzed, as well as a self-catalyzed, growth by a low-temperature metal-organic (MO)CVD process using tBu3Ga as a novel Ga source. Morphology, elemental composition, and crystallinity of the resulting nanowires are analyzed by scanning electron microscopy (SEM), high resolution transmission electron microscopy (HRTEM), energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), and selected area electron diffraction (SAED). Photoluminescence (PL) spectra of the Ga2O3 nanowires show efficient defect-luminescence in the visible and UV ranges with blue and green emission peaks at 430nm and 512 nm, respectively, at room temperature. [ABSTRACT FROM AUTHOR]

The low?temperature metal?organic (MO)CVD of Sb2Te3 films is achieved by the use of the single?source precursor (Et2Sb)2Te, 1. The role of the substrate temperature on the deposition rate and the composition of the resulting film is described. The resulting Sb2Te3 films are characterized by X?ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X?ray (EDX) and Auger spectroscopies. Moreover, the Seebeck coefficient of the Sb2Te3 film deposited at 200?°C is determined, and the value of 160?µV?K?1 demonstrates the high quality and low carrier density of the film. [ABSTRACT FROM AUTHOR]

The low?temperature metal?organic (MO)CVD of Sb2Te3 films is achieved by the use of the single?source precursor (Et2Sb)2Te, 1. The role of the substrate temperature on the deposition rate and the composition of the resulting film is described. The resulting Sb2Te3 films are characterized by X?ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X?ray (EDX) and Auger spectroscopies. Moreover, the Seebeck coefficient of the Sb2Te3 film deposited at 200?°C is determined, and the value of 160?µV?K?1 demonstrates the high quality and low carrier density of the film. [ABSTRACT FROM AUTHOR]

Transition metals (TMs) are highly investigated as nonprecious electrocatalysts for hydrogen evolution (HER) and oxygen evolution (OER) reactions. There is a strong demand for highly efficient and inexpensive catalysts for overall water splitting. Herein, the bimetallic CoxFey alloy nanoparticles encapsulated in a N‐doped graphene shell containing molybdenum carbide (Mo2C) nanoparticles are synthesized by the pyrolysis of cobalt ferrite (CoxFe3−xO4) nanoparticles coated by melamine‐formaldehyde resin cross‐linked with molybdic acid. Molybdic acid not only serves as precursor for the formation of highly dispersed Mo2C nanoparticles in the N‐doped graphene shell but also enhances the thermal stability of the organic shell, resulting in the formation of smaller CoxFey cores. The formation of Mo2C nanoparticles in the graphene shell is promoted by the CoxFe3−xO4 core. Interestingly, the synergistic presence of Mo2C nanoparticles not only enhances the HER activity of the material but also renders a partial breakage of the graphene shell, which increases the surface concentration of OER‐active Co and therefore enhances the OER activity. The as‐prepared TM‐based materials serve as bifunctional catalysts for the overall water splitting and exhibit improved electrocatalytic performances compared to standard cells based on precious metals, with the potentials of 1.53 and 1.60 V at 10 and 20 mA cm−2 in alkaline media, respectively. [ABSTRACT FROM AUTHOR]

Simultaneous electroreduction of CO 2 and H 2 O to syngas can provide a sustainable feed for established processes used to synthesize carbon-based chemicals. The synthesis of MO x /M-N-Cs (M = Ni, Fe) electrocatalysts reported via one-step pyrolysis that shows increased performance during syngas electrosynthesis at high current densities with adaptable H 2 /CO ratios, e.g., for the Fischer-Tropsch process. When embedded in gas diffusion electrodes (GDEs) with optimized hydrophobicity, the NiO x /Ni-N-C catalyst produces syngas (H 2 /CO = 0.67) at -200 mA cm -2 while for the FeO x /Fe-N-C syngas production occurs at ≈-150 mA cm -2 . By tuning the electrocatalyst's microenvironment, stable operation for >3 h at -200 mA cm -2 is achieved with the NiO x /Ni-N-C GDE. Post-electrolysis characterization revealed that the restructuring of the catalyst via reduction of NiO x to metallic Ni NPs still enables stable operation of the electrode at -200 mA cm -2 , when embedded in an optimized microenvironment. The ionomer and additives used in the catalyst layer are important for the observed stable operation. Operando Raman measurements confirm the presence of NiO x during CO formation and indicate weak adsorption of CO on the catalyst surface., (© 2024 The Authors. Small published by Wiley‐VCH GmbH.)

Partially fluorinated β-diketonate complexes M(tfac) 2 (TMEDA) (M = Fe 1, Ni 2, Cu 3, Zn 4; tfac = 1,1,1-trifluoro-2,4-pentanedionate; TMEDA = N , N , N ', N '-tetramethylethylenediamine) were synthesized and structurally (sc-XRD) and thermochemically (TGA) characterised. A new polymorph of Fe(tfac) 2 (TMEDA) was found. The structural and physicochemical properties of 1-4 were compared with related M(acac) 2 (TMEDA) and M(hfac) 2 (TMEDA) (acac = 2,4-pentanedionate, hfac = 1,1,1,5,5,5-hexafluoro-2,4-pentanedionate) β-diketonate complexes to evaluate the effect of the degree of fluorination. A positive effect on the thermal behaviour of the metal acetylacetonates was observed, but no discernible trends. Application of complexes 1-4 as precursors in a MOCVD process yielded either metal (Ni, Cu) or metal oxide thin films (Fe 3 O 4 , ZnO), which were further oxidized to NiO, CuO and α-Fe 2 O 3 films by calcination in air at 500 °C., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Identifying the intrinsic electrocatalytic activity of nanomaterials is challenging, as their characterization usually requires additives and binders whose contributions are difficult to dissect. Herein, we use nano impact electrochemistry as an additive-free method to overcome this problem. Due to the efficient mass transport at individual catalyst nanoparticles, high current densities can be realized. High-resolution bright-field transmission electron microscopy and selected area diffraction studies of the catalyst particles before and after the experiments provide valuable insights in the transformation of the nanomaterials during harsh oxygen evolution reaction (OER) conditions. We demonstrate this for 4 nm sized CoFe 2 O 4 spinel nanoparticles. It is revealed that these particles retain their size and crystal structure even after OER at current densities as high as several kA·m -2 . The steady-state current scales with the particle size distribution and is limited by the diffusion of produced oxygen away from the particle. This versatilely applicable method provides new insights into intrinsic nanocatalyst activities, which is key to the efficient development of improved and precious metal-free catalysts for renewable energy technologies.