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TiO2:Eu3+ nanoparticles with varying europium concentrations were successfully synthesized via a one-pot sol–gel approach using a molecular heterometallic single-source precursor (SSP) Eu-Ti. For comparison, nanomaterials with similar europium levels were also produced by impregnating europium salts onto the same TiO2 substrate. All the nanomaterials were thoroughly characterized using Eu elemental analysis, powder X-ray diffraction (XRD), scanning (SEM), transmission (TEM), scanning transmission electron microscopy (STEM), Brunauer–Emmett–Teller (BET) analysis, thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, and photoluminescence (PL). This low-temperature synthesis yielded crystalline powders, and calcination at 400 °C was performed to remove surface organic impurities, enabling a precise comparison of the final nanomaterials. While both preparation methods produced materials with similarly dispersed and localized dopants on the TiO2 surface, photoluminescence studies revealed that the SSP-derived nanomaterials exhibited significantly superior electro-optical properties. This enhanced efficiency is attributed to the co-hydrolysis of both reactants, which facilitates an optimized interface between the crystalline TiO2 core and the dopant-rich amorphous surface, thereby enabling far more effective charge transfer than that achieved by impregnation. [ABSTRACT FROM AUTHOR]

Aluminium alloys play a crucial role in the aerospace industry due to their lightweight properties and strength. Achieving an acceptable level of corrosion protection of aluminium alloys without chromates remains a challenge. Ongoing research at the author's company focuses on improving corrosion resistance by formulating epoxy systems and exploring additives without the use of Cr. The company's best to-date Cr-free (CF) primer reached 5000 h of salt spray exposure. Additionally, IPTREAT12, a water-based pre-treatment that enhances adhesion and corrosion resistance, was investigated. IPTREAT12, which replaces chromating baths, significantly extended the lifespan of the paint system. When combining Indestructible's surface pre-treatment IPTREAT12 with one of its Cr-free paint formulations, over 6000 h of salt spray resistance were reached. [ABSTRACT FROM AUTHOR]

A new Mitsubishi-type of star-shaped homoleptic derivative of indium(III), In4(mdea)6 ( 2, mdeaH2 = N-methyldiethanolamine), was synthesized by the chloro-aminoalkoxo exchange reaction of a heteroleptic complex In6Cl6(mdea)6 ( 1) and used as a facile single source molecular precursor for the sol-gel preparation of high surface area indium oxide. Successful deposition of gold nanoparticles (1 wt.-%) of average size 3.3 nm on the above metal oxide by using HAuCl4 ·3H2O afforded a highly efficient Au/In2O3 catalyst for the aerobic epoxidation of trans-stilbene at low temperature. The above single source precursor approach was further extended to obtain other group 13 homo- and heterometallic oxides, namely, α-Ga2O3, β-Ga2O3 and Al4Ga2O9, as highly active supports for gold catalysts. The obtained Au/M2O3 (M = Ga, In) and Au/Al4Ga2O9 catalysts were thoroughly characterized by using several physicochemical techniques such as XRD, high resolution transmission electron microscopy (HR-TEM), energy-dispersive X-ray (EDX) spectroscopy, and X-ray photoelectron spectroscopy (XPS). A comparative study of the above catalysts for the model aerobic oxidation of stilbene in methylcyclohexane was undertaken. [ABSTRACT FROM AUTHOR]

Abstract: One-pot deposition of Pd onto TiO2 has been achieved through directly contacting palladium(II) salt with nanosized functionalized TiO2 support initially obtained by sol–gel process using titanium isopropoxide and citric acid. Citrate groups act as functional moieties able to directly reduce the Pd salt avoiding any further reducing treatment. Various palladium salts (Na2PdCl4 and Pd(NH3)4Cl2·H2O) and titanium to citrate (Ti/CA) ratios (20, 50, and 100) were used in order to study the effect of the nature of the precursor and of the citrate content on the final Pd particle size and catalytic properties of the as-obtained Pd/TiO2 systems. Characterization was performed using N2 adsorption–desorption isotherms, ICP-AES, FTIR, XRD, XPS, and TEM. The as-obtained hybrid Pd/TiO2 catalysts were tested in the selective hydrogenation (HYD) of an α,β-unsaturated aldehyde, i.e. cinnamaldehyde. Citrate-free Pd/TiO2-based catalysts present lower selectivity into saturated alcohol. However, citrate-functionalized Pd/TiO2 catalyst seems to control the selectivity, the particle size and dispersion of Pd NPs leading to high intrinsic activity. [Copyright &y& Elsevier]

The metal-support interaction plays an important role in gold catalysis. We employ here crystalline cubic (α-) and hexagonal (β-) phases of heterometallic fluoride NaYF 4 nanoparticles (NPs), obtained by the decomposition of a single source precursor [NaY(TFA) 4 (diglyme)] (TFA = trifluoroacetate), as nonoxide supports for gold catalysts. Using an isostructural gadolinium analogue, we also obtained doped α-NaYF 4 :Gd 3+ and β-NaYF 4 :Gd 3+ NPs. A successful deposition of ∼1% by weight gold NPs of average size 5-6.5 nm on these doped and undoped metal fluorides using HAuCl 4 ·3H 2 O afforded Au/NaYF 4 catalysts which were thoroughly characterized by using several physicochemical techniques such as X-ray diffraction, Brunauer-Emmett-Teller analysis, high-resolution transmission electron microscopy, energy-dispersive X-ray spectrometry, and X-ray photoelectron spectroscopy. A comparative study of the above catalysts for different oxidation reactions show that while for the aerobic oxidation of trans -stilbene in solution phase, they are either better (in terms of stilbene conversion) or at par (in terms of trans -stilbene oxide yield) in comparison to the reference catalyst Au/TiO 2 of the World Gold Council, their activity toward CO oxidation reactions in gas phase remains much less than that of gold catalysts supported on metal oxides., Competing Interests: The authors declare no competing financial interest.