The 2–3 nm size-selected glutathione-capped Ag–In–S (AIS) and core/shell AIS/ZnS quantum dots (QDs) were produced by precipitation/redissolution from an aqueous colloidal ensemble. The QDs reveal broadband photoluminescence (PL) with a quantum yield of up to 60% for the most populated fraction of the core/shell AIS/ZnS QDs. The PL band shape can be described by a self-trapped exciton model implying the PL band being a sequence of phonon replica of a zero-phonon line resulting from strong electron–phonon interaction and a partial conversion of the electron excitation energy into lattice vibrations. It can be concluded that the position and shape of the PL bands of AIS QDs originate not from energy factors (depth and distribution of trap states) but rather from the dynamics of the electron–phonon interaction and the vibrational relaxation in the QDs. The rate of vibrational relaxation of the electron excitation energy in AIS QDs is found to be size-dependent, increasing almost twice from the largest to the smallest QDs.

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The synthesis of nanoscaled β-Bi(2)O(3) starting from the bismuth oxido clusters [Bi(6)O(4)(OH)(4)](NO(3))(6)·H(2)O, [Bi(22)O(26)(OSiMe(2)(t)Bu)(14)], [Bi(38)O(45)(NO(3))(20)(DMSO)(28)](NO(3))(4)·4DMSO and [Bi(38)O(45)(OMc)(24)(DMSO)(9)]·2DMSO·7H(2)O (OMc = O(2)CC(3)H(5)) under ambient conditions is reported. The metal oxido clusters are regarded as ideal precursors for β-Bi(2)O(3) due to their structural relationship with the latter. Nevertheless, different bismuth oxide polymorphs are accessible dependent on the hydrolysis protocol. Hydrolysis over a period of 18 h gave stable α-Bi(2)O(3) whereas after 3 min an amorphous material is observed. Annealing of the amorphous material at 370 °C gave nanoscaled β-Bi(2)O(3). An unusual high reactivity of the β-Bi(2)O(3) particles with SiO(2) and Al(2)O(3) is observed at temperatures above 400 °C. Powder X-ray diffraction studies, transmission electron microscopy, diffuse reflectance UV/Vis spectroscopy and nitrogen adsorption measurements are used for characterization of the as-prepared β-Bi(2)O(3) nanoparticles. The properties of the β-Bi(2)O(3) nanoparticles depend on the starting bismuth oxido clusters with regard to particle size and optical band gap. The β-Bi(2)O(3) nanoparticles show excellent photocatalytic activity as demonstrated by dye decomposition (rhodamine B, methyl orange, methylene blue and orange G) under visible light.

The thermal atomic layer deposition (ALD) of copper oxide films from the nonfluorinated yet liquid precursor bis(tri- n -butylphosphane)copper(I)acetylacetonate, [(Bnu3normalP)C2normalu(acac)] , and wet O2 on Ta, TaN, Ru, and SinormalO2 substrates at temperatures of <160°C is reported. Typical temperature-independent growth was observed at least up to 125°C with a growth-per-cycle of ∼0.1Å for the metallic substrates and an ALD window extending down to 100°C for Ru. On SinormalO2 and TaN, the ALD window was observed between 110 and 125°C , with saturated growth shown on TaN still at 135°C . Precursor self-decomposition in a chemical vapor deposition mode led to bimodal growth on Ta, resulting in the parallel formation of continuous films and isolated clusters. This effect was not observed on TaN up to ∼130°C and neither on Ru or SinormalO2 for any processing temperature. The degree of nitridation of the tantalum nitride underlayers considerably influenced the film growth. With excellent adhesion of the ALD films on all substrates studied, the results are a promising basis for Cu seed layer ALD applicable to electrochemical Cu metallization in interconnects of ultralarge-scale integrated circuits.

Resonant Raman scattering spectra of glass-embedded CdS 1−x Se x nanocrystals are measured and complemented with TEM and optical absorption as well as photoluminescence data. The selectivity of the resonant Raman process not only for the size, but also for the composition of nanocrystals within the ensemble, is directly observed in the dependence of phonon band frequency, linewidth and shape on the excitation wavelength.

Photocatalytic studies under visible light irradiation using nanosized β-Bi2O3 are reported. β-Bi2O3 nanoparticles are prepared starting from the well-defined bismuth oxido cluster [Bi38O45(OMc)24(DMSO)9]⋅2 DMSO⋅7 H2O (OMc=O2CC3H5) using a straightforward hydrolysis and annealing protocol. Powder X-ray diffraction studies, transmission electron microscopy, diffuse reflectance UV/Vis spectroscopy and nitrogen adsorption measurements (using the Brunauer–Emmett–Teller (BET) theory) are used for the characterization of the as-prepared β-Bi2O3. By time-dependent annealing, the crystallite size can be controlled between (17±2) nm and (45±5) nm with BET surface areas of 7 to 29 m2 g−1. The indirect band gap of the as-prepared β-Bi2O3 amounts to (2.15±0.05) eV. The decomposition rates for rhodamine B (RhB) solutions are in the range of 2.46×10−5 to 4.01×10−4 s−1 and depend on the crystallite size, amount of catalyst and concentration of RhB. Photocorrosion experiments have shown the formation of Bi2O2CO3 after several catalytic cycles. However, the catalyst can be recycled to phase-pure β-Bi2O3 nanoparticles by annealing for one hour under argon atmosphere at 380 °C. Furthermore, the photocatalytic activity of as-prepared β-Bi2O3 nanoparticles for the decomposition of phenol, 4-chlorophenol, 2,4-dichlorphenol, 4-nitrophenol, triclosan and ethinyl estradiol is demonstrated.

Ultrasmall (∼2 nm) copper­(I)- and silver­(I)-doped CdS and core/shell CdSe/CdS quantum dots (QDs) stabilized by Cd­(II) complexes with mercaptoacetate anions and ammonia were produced in aqueous solutions. The doped QDs emit broadband visible photoluminescence (PL) with a quantum yield reaching 10–12% for Cu+-doped QDs and 5–9% for Ag+-doped QDs. The broadband PL was described by a self-trapped exciton model as a sequence of phonon replicas of a zero-phonon emission line. The shape of the PL bands of CdS, Cu+-doped CdS QDs, and Ag+-doped CdS QDs was modeled by using the energies of optical phonons of CdS, CuS, and Ag2S, respectively. The dependence of the average PL lifetime of both pristine and doped CdS and CdSe/CdS QDs on PL registration wavelength was interpreted in terms of the vibrational relaxation of the self-trapped exciton. The analysis of PL properties of different ultrasmall metal chalcogenide QDs showed that the broadband PL can be described by a general model which does not require the assumption of participation of charge-trapping lattice defects.

The reaction of [Bi6O4(OH)4](NO3)6·H2O with triflic acid gave colorless single crystals of [Bi6O4(OH)4(OTf)6(CH3CN)6]·2CH3CN (1) upon crystallization from acetonitrile/chloroform. Compound 1 crystallizes in the monoclinic space group P21/n. The novel hexanuclear bismuth oxido cluster is highly soluble in water and polar organic solvents. A transparent and water‐soluble hybrid material was obtained by reaction of [Bi6O4(OH)4(OTf)6(CH3CN)6]·2CH3CN (1) with polyacrylate in aqueous solution. Molecular dynamics simulations were performed to study the complexation behavior of the [Bi6O4+x(OH)4–x](6–x)+ cation with polyacrylate in solution.