Synthetic methods that allow for the controlled design of well-defined Pt nanoparticles are highly desirable for fundamental catalysis research. In this work, we propose a strategy that allows precise and independent control of the Pt particle size and coverage. Our approach exploits the versatility of the atomic layer deposition (ALD) technique by combining two ALD processes for Pt using different reactants. The particle areal density is controlled by tailoring the number of ALD cycles using trimethyl(methylcyclopentadienyl)platinum and oxygen, while subsequent growth using the same Pt precursor in combination with nitrogen plasma allows for tuning of the particle size at the atomic level. The excellent control over the particle morphology is clearly demonstrated by means of in situ and ex situ X-ray fluorescence and grazing incidence small angle X-ray scattering experiments, providing information about the Pt loading, average particle dimensions, and mean center-to-center particle distance.

A vapor-fed solar hydrogen generator with KOH-doped poly(vinyl alcohol) anion exchange membrane flanked with NiFe and NiMo catalysts is demonstrated.

A plasma-enhanced atomic layer deposition (ALD) process using the Ag(fod)(PEt 3 ) precursor [(triethylphosphine) (6,6,7,7,8,8,8-heptafluoro-2,2-dimethyl-3,5octanedionate)silver(I)] in combination with NH 3 -plasma is reported. The steady growth rate of the reported process (0.24 ± 0.03 nm/cycle) was found to be 6 times larger than that of the previously reported Ag ALD process based on the same precursor in combination with H 2 -plasma (0.04 ± 0.02 nm/ cycle). The ALD characteristics of the H 2 -plasma and NH 3plasma processes were verified. The deposited Ag films were polycrystalline face-centered cubic Ag for both processes. The film morphology was investigated by ex situ scanning electron microscopy and grazing-incidence small-angle X-ray scattering, and it was found that films grown with the NH 3 -plasma process exhibit a much higher particle areal density and smaller particle sizes on oxide substrates compared to those deposited using the H 2 -plasma process. This control over morphology of the deposited Ag is important for applications in catalysis and plasmonics. While films grown with the H 2 -plasma process had oxygen impurities (∼9 atom %) in the bulk, the main impurity for the NH 3 -plasma process was nitrogen (∼7 atom %). In situ Fourier transform infrared spectroscopy experiments suggest that these nitrogen impurities are derived from NH x surface groups generated during the NH 3 -plasma, which interact with the precursor molecules during the precursor pulse. We propose that the reaction of these surface groups with the precursor leads to additional deposition of Ag atoms during the precursor pulse compared to the H 2 -plasma process, which explains the enhanced growth rate of the NH 3 -plasma process.

Coils for pulsed magnetic fields were developed using layer by layer reinforcement with fibre composite material. The thickness of each individual layer of the reinforcement was optimized using a simple 'finite element' calculation method. A machine was designed and built that allows the winding of a layer of fibre rovings of precisely controlled thickness between the layers of wire. So far, a field of 58 T has been obtained in a 20 mm bore; in a 12 mm bore a maximum field of 66.9 T resulted in destruction of the coil.

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