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Bidentate diamine and amino‐alcohol ligands have been used to form solid, water‐soluble, and air‐stable monomeric copper complexes of the type [Cu(NH2CH2CH(R)Y)2(NO3)2] (1, R=H, Y=NH2; 2, R=H, Y=OH; 3, R=Me, Y=OH). The complexes were characterized by elemental analysis, mass spectrometry, infrared spectroscopy, thermal gravimetric analysis, and single‐crystal X‐ray diffraction. Irrespective of their decomposition temperature, precursors 1–3 yield highly conductive copper features [1.5×10−6 Ω m (±5×10−7 Ω m)] upon atmospheric‐pressure plasma‐enhanced sintering. Hot off the press: Bidentate diamine and amino‐alcohol ligands are used to form solid, water‐soluble, and air‐stable monomeric copper complexes. Irrespective of their decomposition temperature, the precursors each yield highly conductive copper features upon atmospheric‐pressure plasma‐enhanced sintering. [ABSTRACT FROM AUTHOR]

For the first time, the plasma‐assisted inkjet printing of metal‐organic decomposition (MOD) inks is demonstrated to provide an easily up‐scalable method toward the deposition of highly conductive silver features on paper. Atmospheric plasma sintering methods provide a fast and effective alternative to thermal treatment. This high‐speed, room‐temperature approach ensures the immediate conversion of the MOD inks after printing and thus overcomes wetting issues typically encountered in porous substrates—a mechanical solution to a chemical problem. [ABSTRACT FROM AUTHOR]

Aerosol assisted chemical vapour deposition (AACVD) has been used to deposit thin films of ZnO from the single-source precursor [Zn(OC(Me)CHC(Me)N( i Pr)) 2 ] ( 1 ) affording highly transparent (>80%) and conductive films (sheet resistance ∼70 KΩ/sq). Extension of this AACVD method whereby related precursors of the type, [R 2 M(OC(Me)CHC(Me)N( i Pr))] (R = Et, M = Al ( 2 ); R = Me, M = Ga ( 3 )), isolated as oils, were added to the precursor solution allowed for the deposition of aluminium- and gallium-doped ZnO (AZO and GZO) films, respectively. Complexes 1 – 3 were characterised by elemental analysis, NMR and mass spectrometry. Films were deposited in under 30 min at 400 °C, from CH 2 Cl 2 /toluene solutions with a N 2 carrier gas. Herein we report the bulk resistivity, ρ , of AZO (0.252 Ω cm) and GZO (0.756 Ω cm) films deposited from this novel approach. All the films transparency exceeded 80% in the visible, X-ray diffraction (XRD) showed all films to crystallise in the wurtzite phase whilst X-ray photoemission spectroscopy (XPS) confirmed the presence of the Al and Ga dopants in the films, and highlighted the low C-contamination (<5%) this route offers. Investigation of a mechanism analogous to the Kirkendall effect confirmed that heating of GZO films at 1000 °C produced the spinel structure GaZn 2 O 4 . [ABSTRACT FROM AUTHOR]

The use of zinc triflate (trifluoromethanesulfonate), [Zn(OTf) 2 ] as a precursor in the aerosol assisted chemical vapour deposition of zinc oxide thin films is described. Aluminum doped zinc oxide (AZO) thin films are also shown to be deposited when aluminum acetylacetonate [Al(acac) 3 ] was introduced into the precursor solution, illustrating the versatility of this system. Film characterization techniques include glancing angle X-ray powder diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy and optical and electrical measurements. AZO films with an Al content of 7 at.% were found to have favourable transparent conducting oxide properties with simultaneous high transparency (> 80%) in the visible light region and a low electrical resistivity (1.96 × 10 − 3 Ω cm). [ABSTRACT FROM AUTHOR]

A conventional solution-based route to a cyclic trimeric organozinc compound [{Zn(Et)( β-diketonate)}3] ( β-diketonate=OC(OMe)CHC(Me)O, 1) is described, with 1 structurally characterized for the first time. The ligand selection of bidentate β-diketonates is shown to be key to isolating a cyclic trimer. Additional reaction of β-diketonates with diethyl zinc were spectroscopically characterized as compounds of the type [{Zn(Et)( β-diketonate)} n] ( β-diketonate=OC(Me)CHC(Me)O, 2, OC(O tBu)CHC(Me)O, 3). Further studies have shown that selective oxidation of these species produces cubanes of the general formula [{Zn(OC(R)CHC(Me)O)2Zn(Et)OEt}2] (R=OMe, 4; Me, 5; O tBu, 6), allowing a high oxygen content whilst remaining structurally suitable for use as precursors. The successful deposition of thin films of zinc oxide through aerosol-assisted chemical vapor deposition (AACVD), using a novel precursor, is described and fully characterized. [ABSTRACT FROM AUTHOR]

A systematic study detailing the uptake of a series of chemically related simple functionalized aromatic guest molecules into the pores of the crystalline sponge [{(ZnI2)3(tris(4-pyridyl)-1,3,5-triazine)2·x(solvent)}n] has been performed. The reproducible positioning of the guest molecules within the unit cell has been documented. Analysis of guest-host and guest-guest interactions has shown the dominant role of π⋯π and CH⋯π interactions in the ability of the crystalline sponge to render the guest molecules regularly ordered. Further interactions specific to guest functionality, such as weak hydrogen bonds, are seen to contribute to the particular orientation of the guests. [ABSTRACT FROM AUTHOR]

Novel lead and bismuth dipyrido complexes have been synthesized and characterized by single-crystal X-ray diffraction, which shows their structures to be directed by highly oriented π-stacking of planar fully conjugated organic ligands. Optical band gaps are influenced by the identity of both the organic and inorganic component. Density functional theory calculations show optical excitation leads to exciton separation between inorganic and organic components. Using UV-vis, photoluminescence, and X-ray photoemission spectroscopies, we have determined the materials' frontier energy levels and show their suitability for photovoltaic device fabrication by use of electron- and hole-transport materials such as TiO2 and spiro-OMeTAD respectively. Such organic/inorganic hybrid materials promise greater electronic tunability than the inflexible methylammonium lead iodide structure through variation of both the metal and organic components. [ABSTRACT FROM AUTHOR]

This critical review focuses on the solution based chemical vapour deposition (CVD) of main group materials with particular emphasis on their current and potential applications. Deposition of thin films of main group materials, such as metal oxides, sulfides and arsenides, have been researched owing to the array of applications which utilise them including solar cells, transparent conducting oxides (TCOs) and window coatings. Solution based CVD processes, such as aerosol-assisted (AA)CVD have been developed due to their scalability and to overcome the requirement of suitably volatile precursors as the technique relies on the solubility rather than volatility of precursors which vastly extends the range of potentially applicable compounds. An introduction into the applications and precursor requirements of main group materials will be presented first followed by a detailed discussion of their deposition reviewed according to this application. The challenges and prospects for further enabling research in terms of emerging main group materials will be discussed. [ABSTRACT FROM AUTHOR]

The β-ketoimine ligand [(Me)CN(H){iPr}–CHC(Me)=O] (L1H) and the bis(β-ketoimine) ligands [(CH2)2{N(H)C(Me)–CHC(R)=O}2] (L2H2, R = Me; L3H2, R = C6H5) linked by ethylene bridges have been used to form aluminium and gallium complexes: [Al(L1)Et2] (1), [Ga(L1)2Cl] (2), [AlL2(OiPr)] (3) and [GaL3Me] (4). The complexes were characterised by NMR spectroscopy, mass spectroscopy, and single crystal X-ray diffraction, with the exception of 1 which was isolated as an oil. Compounds 1–4 have been used for the first time as single source precursors for the deposition of Al2O3 (1, 3) and Ga2O3 (2, 4) respectively. Thin films were deposited via aerosol assisted (AA)CVD with toluene as the solvent. [ABSTRACT FROM AUTHOR]

Single-source zinc β-iminoesterate precursors have been used for the first time in the aerosol-assisted chemical-vapour deposition (AACVD) of ZnO thin films. Depositions at 450 °C on silica-coated glass substrates produced strongly adherent films with excellent coverage of the substrate. The zinc β-iminoesterates [Zn(L1)2] ( 1) and [Zn(L2)2] ( 2) were synthesised by the reaction between ZnEt2 and 2 equiv. of a synthesised β-iminoester ligand CH3C[NHCH(CH3)2]CHC(O)OCH2CH3 (L1) and CH3C(NHCH3)CHC(O)OCH2CH3 (L2). The synthesised complexes were isolated and characterised by 1H and 13C NMR spectroscopy, mass spectrometry and thermal gravitational analysis (TGA). The structures of the compounds were determined by single-crystal X-ray diffraction. The ZnO films deposited from 1 and 2 were analyzed by glancing-angle X-ray powder diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and their optical properties determined by UV/Vis/NIR transmission spectroscopy. These results reveal that the organic ligand attached to the N moiety of the zinc complex has a significant effect on the level of carbon incorporated into the deposited thin film. Upon annealing, highly transparent hexagonal wurtzite ZnO thin films were produced. [ABSTRACT FROM AUTHOR]

Aerosol-assisted chemical vapour deposition (AACVD) reactions of GaMe3, ZnEt2 and the donor-functionalised alcohol HOCH2CH2OMe (6 equiv.) in toluene resulted in the deposition of amorphous transparent zinc gallate (ZnGa2O4) films at a range of temperatures (350-550 °C). The zinc-gallium oxide films were analyzed by scanning electron microscopy, X-ray photoelectron spectroscopy (XPS), energy-dispersive X-ray analysis, glancing-angle X-ray powder diffraction (XRD) and optical studies. The optimum growth temperature was found to be 450 °C, which produced transparent films with excellent coverage of the substrate. XPS confirmed the presence of zinc, gallium and oxygen in the films. Annealing these films at 1000 °C resulted in crystalline films and glancing-angle powder XRD showed that a zinc gallate spinel framework with a lattice parameter of a=8.336(5) Å was adopted. [ABSTRACT FROM AUTHOR]

Copper-based spinel oxide CuGa2O4 films have been deposited by means of a simple one-pot solution-based chemical vapour deposition (CVD) method. Aerosol-assisted (AA) CVD of copper(II) 2,2,6,6,-tetramethylheptan-3,5-dionate (thd), Cu(thd)2 and gallium(III) acetylacetonate, Ga(acac)3, in toluene resulted in the formation of transparent films with a slight yellow tinge at 300-500°C. Scanning electron microscopy (SEM) indicated that the films had grown by means of an island growth mechanism. Energy-dispersive X-ray (EDX) analysis and X-ray photoelectron spectroscopy (XPS) showed that CuGa2O4 had formed along with copper(I) oxide and gallium(III) oxide was observed at the surface of the film. Annealing the films under a range of conditions (air, N2, vacuum) resulted in oxidation and the formation of CuGa2O4 and copper(II) oxide, as shown by powder X-ray diffraction (XRD). The films were further analysed by UV/ Vis spectroscopy and atomic force microscopy. Similar AACVD depositions using copper(II) acetylacetonate, Cu(acac)2, and Ga(acac)3 in a range of solvents only resulted in the formation of gallium oxide owing to the lower solubility of the copper precursor than the gallium complex. AACVD is dependent on the precursor solubility hence Cu(thd)2 is a superior precursor to Cu(acac)2 owing to its increased solubility. [ABSTRACT FROM AUTHOR]

The molecular structures of the vapors produced on heating dimethylalkoxygallanes of the type [Me2Ga(OR)]2 have been determined by gas electron diffraction and ab initio molecular orbital calculations. In the solid state [Me2Ga(OCH2CH2NMe2)]2 (1) and [Me2Ga(OCH2CH2OMe)]2 (2) adopt dimeric structures, although only the monomeric forms [Me2Ga(OCH2CH2NMe2)] (1a) and [Me2Ga(OCH2CH2OMe)] (2a) were observed in the gas phase. For comparison the structure of the vapor produced on heating [Me2Ga(OtBu)]2 (3) was also studied by gas electron diffraction. In contrast to 1 and 2, compound 3 is dimeric in the gas phase, as well as in the solid state. The gas-phase structures of 1a and 2a exhibit five-membered rings formed by a dative bond between Ga and the donor atom (N or O) from the donor-functionalized alkoxide. In 3 there is no possibility of a monomeric structure being stabilized by the formation of such a dative bond since only a monofunctional alkoxide is present in the molecule. [ABSTRACT FROM AUTHOR]

The group 13 monoalkoxometallanes [Me_{2}Ga(OC(CH_{3})_{2}CH_{2}OMe)]_{2} (1) and [Me_{2}In(OCH(CH_{3})CH_{2}OMe)]_{2} (2), incorporating donor functionalised alkoxides, were synthesised from the reaction of GaMe_{3} or InMe_{3} with ROH (R=C(CH_{3})_{2}CH_{2}OMe (1); R=CH(CH_{3})CH_{2}OMe (2)) in toluene. X-ray crystallography showed that both compounds adopt dimeric structures with a planar M_{2}O_{2} ring, and each group 13 atom is coordinated in a distorted trigonal bipyramidal geometry. The AACVD reaction of GaMe_{3} and ROH (R =C(CH_{3})_{2}CH_{2}OMe, CH_{2}CH_{2}OMe, CH_{2}CH_{2}NMe_{2}) resulted in the formation of thin films of Ga_{2}O_{3} on glass substrates at 450°C. The gallium oxide films were analyzed by scanning electron microscopy, X-ray powder diffraction, energy dispersive analysis of X-rays, wavelength dispersive analysis of X-rays and X-ray photoelectron spectroscopy. This CVD technique offers a rapid, convenient route to Ga_{2}O_{3}, which involves the in situ formation of dimethylgallium alkoxides, of the type [Me_{2}Ga(μ-OR)]_{2} similar to compound 1. [ABSTRACT FROM AUTHOR]

Highly transparent (>85 %) and conductive (1.086×10−3 Ω cm) zinc oxide thin films have been deposited from specifically selected precursors allowing us to establish a direct correlation between their molecular structure and the optoelectronic properties of the deposited films. Mono‐ligated ethyl zinc compounds of varying steric bulk: [EtZn(OC(Me)CH(Me)N(iPr))]2 (1), [EtZn(OC(OEt)CH(Me)N(iPr))]2 (2) and [EtZn(OC(OEt)CH(CH3)N(Dipp))]2 (3) were compared with the related bis‐ligated zinc complexes [Zn(OC(Me)CH(Me)N(iPr))2] (4), [Zn(OC(OEt)CH(Me)N(iPr))2] (5) and [Zn(OC(OEt)CH(Me)N(Dipp))2] (6). In all cases bulkier ligands resulted in poorer electronic properties of deposited films, whilst all mono‐ligated compounds were shown as superior precursors. All complexes were characterised by 1H and 13C{1H} NMR and elemental analysis, with the structure of 6 determined by single crystal X‐ray diffraction. Zinc oxide films were deposited from single and dual source (with methanol) reactions of these precursors, and analysed via XRD, XPS and EDX. Optoelectronic properties were investigated through UV/vis spectroscopy and Hall effect measurements, and morphology was examined via SEM. Tauc plots from UV/vis data indicated that Film A showed the lowest band gap of 3.31 eV. Varying the elemental composition of the precursors led to changes in the elemental composition of the resultant films, as well as changes in their structural and optoelectronic properties. Using this approach of precursor design, we have been able to tune single source precursors towards zinc oxide to deposit films with specific properties. [ABSTRACT FROM AUTHOR]

Amidoenoate (AME = {ethyl-3-(R-amido)but-2-enoate}) complexes of aluminium and gallium, of the type: [AlCl2(AMER)] R = iPr (1-Al); [AlCl(AMER)2] R = iPr (2-Al), Dip (3-Al); [GaCl2(AMER)] R = iPr (1-Ga) and [GaCl(AMER)2] R = iPr (2-Ga), Dip (3-Ga), have been synthesised (iPr = isopropyl, Dip = 2,6-diisopropylphenyl). The coordination chemistry of these complexes has been studied in relation to precursor suitability. Investigations into the reactivity of the aluminium and gallium amidoenoate complexes involved reactions with hydride sources including alkali metal hydride salts, alkylsilanes, and magnesium hydride species and magnesium(I) dimers. The isolation of alkyl metal amidoenoate precursors including an aluminium hydride amidoenoate, [AlH(AMEDip)2] (4-Al) and dimethyl gallium amidoenoates [GaMe2(AMEDip)] (4-Ga), [GaMe2(AMEiPr)] (5-Ga) concluded the synthetic studies. A selection of the isolated complexes were used as precursors for aerosol assisted chemical vapour deposition (AACVD) at 500 °C. Thin films of either amorphous Al2O3 or Ga2O3 were deposited and subsequently annealed at 1000 °C to improve the materials' crystallinity. The films were characterised by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), UV-visible (UV-vis) spectroscopy and energy dispersive X-ray analysis (EDXA). [ABSTRACT FROM AUTHOR]

This Minireview compares two distinct ink types, namely metal‐organic decomposition (MOD) and nanoparticle (NP) formulations, for use in the printing of some of the most conductive elements: silver, copper and aluminium. Printing of highly conductive features has found purpose across a broad array of electronics and as processing times and temperatures reduce, the avenues of application expand to low‐cost flexible substrates, materials for wearable devices and beyond. Printing techniques such as screen, aerosol jet and inkjet printing are scalable, solution‐based processes that historically have employed NP formulations to achieve low resistivity coatings printed at high resolution. Since the turn of the century, the rise in MOD inks has vastly extended the range of potentially applicable compounds that can be printed, whilst simultaneously addressing shelf life and sintering issues. A brief introduction to the field and requirements of an ink will be presented followed by a detailed discussion of a wide array of synthetic routes to both MOD and NP inks. Unindustrialized materials will be discussed, with the challenges and outlook considered for the market leaders: silver and copper, in comparison with the emerging field of aluminium inks. [ABSTRACT FROM AUTHOR]

The Cover Feature shows bidentate diamine and amino‐alcohol ligands, which are used to form solid, water‐soluble, and air‐stable monomeric copper complexes for low‐temperature plasma‐assisted inkjet printing of conductive copper. More information can be found in the Full Paper by C. E. Knapp et al. on page 850 in Issue 11, 2018 (DOI: 10.1002/open.201800131). [ABSTRACT FROM AUTHOR]

The developments in inkjet printing technology and the printed electronics industry in the past two decades have provided cost-effective, environmentfriendly, and reliable alternates to traditional methods of fabricating electrical devices. However, most commercial metallic inks require high sintering temperatures to form desired functional patterns, which limits the applications of printed electronics in scenarios that require electrical devices on thermally sensitive substrates, like biomaterials or bio-synthetic composite materials. This study provides the synthetic route of a novel silver-based metal organic decomposition (MOD) ink which is used to form highly conductive silver films on the thermally sensitive skin-inspired silk/epoxy composite substrates by directly inkjet printing with accurate pattern control, whilst self-decomposing and sintering at room temperature. The fabricated silver patterns on the thermally sensitive silk/epoxy composite substrate are highly conductive with conductivity of 4.65 × 104 S m-1. These silver patterns also show impressive malleability as bulk silver films, which can be further developed into motion sensors for wearable devices or medical applications. Our strategy provides a general platform for electronic functionalization without temperature constraints. The particle-free, reactive silver-precursor, and lower sintering temperature of the ink also widen the choices of substrates, as exemplified herein with outstanding printing quality and high electrical conductivity (1.20 × 106 S m-1) also achieve on paper. [ABSTRACT FROM AUTHOR]

The field of printed electronics strives for lower processing temperatures to move toward flexible substrates that have vast potential: from wearable medical devices to animal tagging. Typically, ink formulations are optimized using mass screening and elimination of failures; as such, there are no comprehensive studies on the fundamental chemistry at play. Herein, findings which describe the steric link to decomposition profile: combining density functional theory, crystallography, thermal decomposition, mass spectrometry, and inkjet printing, are reported. Through the reaction of copper(II) formate with excess alkanolamines of varying steric bulk, tris‐co‐ordinated copper precursor ions: "[CuL3]," each with a formate counter‐ion (1–3) are isolated and their thermal decomposition mass spectrometry profiles are collected to assess their suitability for use in inks (I1–3). Spin coating and inkjet printing of I1,2 provides an easily up‐scalable method toward the deposition of highly conductive copper device interconnects (ρ = 4.7–5.3 × 10−7 Ω m; ≈30% bulk) onto paper and polyimide substrates and forms functioning circuits that can power light‐emitting diodes. The connection among ligand bulk, coordination number, and improved decomposition profile supports fundamental understanding which will direct future design. [ABSTRACT FROM AUTHOR]

Vanadium(V) oxytrichloride was reacted with 2,4-pentanedione, diethyl malonate, and diethyl succinate under inert conditions, forming compounds: dichloro(oxo)(2,4-pentanedione) vanadium(V) [ 1 ], dichloro(oxo)(diethyl malonate) vanadium(IV) [ 2 ] and dichloro(oxo)(diethyl succinate) vanadium(IV) [ 3 ]. Compounds 1 – 3 are coordinated to the vanadium centre through the two carbonyl oxygen atoms of the bidentate ligand. It was determined by X-ray crystallography that the structures of the resulting complexes were significantly different, resulting in a monomeric complex ( 1 ), a tetrameric ring ( 2 ) and a 1D coordination polymer ( 3 ). Following the synthesis and isolation of 1 – 3 , they were tested as precursors for vanadium nitride and vanadium carbide by annealing under nitrogen and argon respectively at 1200 °C for 24 h. The resulting materials were characterised by: XRD, EDS, XPS and TEM. [ABSTRACT FROM AUTHOR]

Precursor design is the crucial step in tailoring the deposition profile towards a multitude of functional materials. Most commercially available aluminium oxide precursors require high processing temperatures (>500 °C). Herein, we report the tuning of the decomposition profile (200–350 °C) of a range of octahedrally coordinated tris(β‐ketoiminate) aluminium complexes of the type [Al(MeCN(R)CHC=OMe)3], by varying the R substituents in the ligands. The complexes are derived from the reaction of trimethylamine alane (TMAA) and a series of N‐substituted β‐ketoiminate ligands (R‐acnacH, R=Me, Et, iPr, Ph) with varying R‐substituents sizes. When the more sterically encumbered ligand (R=Mes) was used, the Al atom became five‐coordinate, therefore representing the threshold to octahedral coordination around the metal in these type of compounds, which, consequently, lead to a change of decomposition profile. The resulting compounds have been characterised by NMR spectroscopy, mass spectrometry, elemental analysis and single crystal X‐ray diffraction. [Al(MeCN(Me)CHC=OMe)3] has been used as a single source precursor for the deposition of Al2O3. Thin films were deposited via aerosol assisted chemical vapour deposition (AACVD), with toluene as the solvent, and were analysed using SEM, EDX and XPS. [ABSTRACT FROM AUTHOR]

Titanium(IV) chloride and the triester glycerol tribenzoate (gtb) were reacted under moisture-free conditions in order to investigate the use of triester-containing oils in the purification of TiCl4 in industrial processes. This resulted in the isolation of a chloro-bridged dimeric complex containing four titanium centres [{(TiCl4)2(gtb)}2] ( 1). Further novel coordination compounds of TiCl4 and the diesters; diisopropyl malonate, dibenzyl malonate and diethyl succinate were synthesised by direct reaction under moisture-free conditions, yielding [TiCl4{CH2(COO iPr)2}] ( 2), [TiCl4{CH2(COOCH2Ph)2}] ( 3) and [TiCl4{C2H4(COOEt)2}] ( 4) respectively. The structures of compounds 1- 4 were determined by single-crystal X-ray diffraction. All structures assumed an octahedral geometry consisting of the titanium bound to four chloride ligands and the diester molecule acting as a bidentate ligand, through its two carbonyl oxygen atoms. Exposure of the isopropyl malonate reaction to trace amounts of water during synthesis resulted in the formation of an oxo-bridged dimeric structure [Ti2(μ-O)Cl3{CH2(COO iPr)2}2] ( 2b), the structure of which was also obtained via single-crystal X-ray diffraction. [ABSTRACT FROM AUTHOR]

Silver (Ag) amidinate metal organic decomposition precursors of the type: [Ag2((ArN)2C(H))2] (Ar = 2,6-dimethylphenyl (1), 2,6-diethylphenyl (2) and 2,6-diisopropylphenyl (3)) have been used for the first time in the deposition of Ag films on glass with multiple functionalities with potential application in optical/biological sensors or for use in electronic circuitry. Precursors 1–3 were isolated from the reaction of silver acetate with the appropriate ligand in a 1:2 stoichiometry and were characterized by 1H and 13C{1H} NMR, thermal gravimetric analysis and single crystal X-ray diffraction for 2. Single-layer depositions at 200 °C on glass substrates via spin coating produced transparent (>90% transmittance) coatings, with well-defined Ag nanoparticles. Multi-layer depositions at 200 °C on glass had a metallic lustre and were found to be conductive (ρ = 0.916–1.83 × 10−6 Ωm). All films were strongly adhered and displayed excellent coverage of the substrate. Ag films deposited from 1 to 3 were analysed by grazing incidence X-ray diffraction, X-ray photoelectron spectroscopy, energy-dispersive X-ray analysis and scanning electron microscopy, with optical properties determined by UV-Vis spectroscopy. [ABSTRACT FROM AUTHOR]

Formally, triple-bonded dimetallynes ArEEAr [E = Ge (1), Sn (2); Ar = C6H3-2,6-(C6H3-2,6-iPr2)2] have been previously shown to activate aliphatic, allylic C-H bonds in cyclic olefins, cyclopentadiene (CpH), cyclopentene (c-C5H8) and 1,4-cyclohexadiene, with intriguing selectivity. In the case of the five-membered carbocycles, cyclopentadienyl species ArECp [E = Ge (3), Sn (4)] are formed. In this study, we examine the mechanisms for activation of CpH and c-C5H8 using experimental methods and describe a new product found from the reaction between 1 and c-C5H8, an asymmetrically substituted digermene ArGe(H)Ge(c-C5H9)Ar (5), crystallized in 46% yield. This compound contains a hydrogenated cyclopentyl moiety and is found to be produced in a 3:2 ratio with 3, explaining the fate of the liberated H atoms following triple C-H activation. We show that when these C-H activation reactions are carried out in the presence of tert-butyl ethylene (excess), compounds {ArE(CH2CH2tBu)}2 [E = Ge(8), Sn(9)] are obtained in addition to ArECp; in the case of CpH, the neohexyl complexes replace the production of H2 gas, and for c-C5H8 they displace cyclopentyl product 5 and account for all the hydrogen removed in the dehydroaromatization reactions. To confirm the source of 8 and 9, it was demonstrated that these molecules are formed cleanly between the reaction of (ArEH)2 [E = Ge(6), Sn(7)] and tert-butyl ethylene, new examples of noncatalyzed hydro-germylation and -stannylation. Therefore, the presence of transient hydrides of the type 6 and 7 can be surmised to be reactive intermediates in the production of 3 and 4, along with H2, from 1 and 2 and CpH (respectively), or the formation of 3 and 5 from 1. The reaction of 6 or 7 with CpH gave 3 or 4, respectively, with concomitant H2 evolution, demonstrating the basic nature of these low-valent group 14 element hydrides and their key role in the 'cascade' of C-H activation steps. Additionally, during the course of these studies a new polycyclic compound (ArGe)2(C7H12) (10) was obtained in 60% yield from the reaction of 1,6-heptadiene and 1 via double [2 + 2] cycloaddition and gives evidence for a nonradical mechanism for these types of reactions. [ABSTRACT FROM AUTHOR]

A set of heteroleptic ethyl zinc β-amidoenoates (1, 2) and β-ketoiminates (3) of the form [LZnEt]2 with varying steric bulk have been synthesised via the reaction of diethylzinc with β-aminoenoate ligands HL1 and HL2 and β-ketoimine HL3. These complexes have been characterised via 1H and 13C NMR, mass spectrometry and single-crystal X-ray diffraction, which unambiguously determined all three structures as dimeric species in the solid state. We observe the unusual dimerisation of 1 and 2 through coordination of the central zinc atom to the methine carbon of the second monomer, which gives these complexes high reactivity. The thermal properties of complex 3 are explored via thermal gravimetric analysis (TGA), to investigate their potential as single-source precursors to zinc oxide, which shows that 3 has a significantly lower decomposition temperature as compared to its bis-ligated counterpart [Zn(L3)2], which gives 3 promise as a single-source precursor to zinc oxide. [ABSTRACT FROM AUTHOR]

Although nanoparticle (NP) inks are well known, the rise in metal-organic decomposition (MOD) inks has extended the range of compounds that can be printed, whilst simultaneously addressing shelf life and sintering issues. Conductivity, inks, nanoparticle, precursor, printing Keywords: conductivity; inks; nanoparticle; precursor; printing EN conductivity inks nanoparticle precursor printing 1 1 1 06/05/21 20210601 NES 210601 B Printing of highly conductive b features has found purpose across a broad array of electronics and as processing times and temperatures reduce, the avenues of application expand to low-cost flexible substrates, materials for wearable devices and beyond. [Extracted from the article]

There is currently an enormous drive to move away from the use of Pt group metals in catalysis, particularly for fuel cells, because of their increasing rarity and cost. Simultaneously, there have been advances in the application of graphene supported nanoparticular catalysts. However, these Pt-free, graphene supported catalysts can be complex to produce, show poor catalytic activity and degrade quickly due to particle agglomeration or isolation. Herein, we report a one-pot synthesis of silver nanoparticles (NPs) tethered to a reduced graphene oxide (rGO) template via organic linkages. This is one of the few silver precursor formations that have been combined with graphene oxide (GO) to simultaneously establish linkage binding sites, reduce GO and yield tethered nanoparticles. These materials are shown to efficiently catalyze the oxygen reduction reaction in alkaline environments, with aminoethanol linkages to 21.55 ± 2.88 nm Ag particles exhibiting the highest catalytic activity via the four-electron pathway. This method, therefore, offers a straightforward route to produce effective catalysts from inexpensive precursors, which could be developed further for significant industrial application. [ABSTRACT FROM AUTHOR]

Macrocyclic [Fe(η5-C5H4Se)2M(η5-C5H4R)2]2 [M = Ti (1), Zr (2), Hf (3), R = H; and M = Zr (4), Hf (5), R = tBu] were prepared and characterized by 77Se NMR spectroscopy and the crystal structures of 1–3 and 5 were determined by single-crystal X-ray diffraction. The crystal structure of 4 is known and the complex is isomorphous with 5. 1–5 form mutually similar macrocyclic tetranuclear complexes in which the alternating Fe(C5H4Se)2 and M(C5H4R)2 centers are linked by selenium bridges. The thermogravimetric analysis (TGA) of 1–3 under a helium atmosphere indicated that the complexes undergo a two-step decomposition upon heating. The final products were identified using powder X-ray diffraction as FexMSe2, indicating their potential as single-source precursors for functional materials. [ABSTRACT FROM AUTHOR]

Molybdenum-doped indium oxide (IMO) thin films prepared by aerosol-assisted chemical vapor deposition (AACVD) show significantly improved charge carrier mobilities as compared to nominally undoped films prepared by the same technique. The basis for this very unusual behavior has been investigated by density functional theory calculations using a hybrid Hamiltonian, mobility modeling, X-ray photoemission, and X-ray absorption spectroscopies. In contrast to previous claims that Mo acts as a three-electron donor, it is shown that substitutional Mo traps two electrons in localized states falling within the bulk bandgap and thus Mo is a simple oneelectron donor. At the same time, there is very little hybridization of Mo 4d states with In 5s states at the bottom of the conduction band. This results in conduction that is spatially separated to some degree from the donors, giving rise to significantly reduced ionized impurity scattering, enhancing the carrier mobility. This is in contrast to Sn-doped In2O3 where the conduction band minimum has significant Sn 5s character, resulting in regular ionized impurity scattering. [ABSTRACT FROM AUTHOR]