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In this study Ru3 clusters are deposited onto radio frequency-sputter deposited TiO2 (RF-TiO2) substrates by both solution submersion and chemical vapor deposition (CVD) of Ru3(CO)12, as well as cluster source depositions of bare Ru3. TiO2(100) and SiO2 are used as comparison surfaces with differing cluster-surface interactions. Temperature-dependent X-ray photoelectron spectroscopy (XPS), angle-resolved XPS, and temperature-dependent low energy ion scattering (TD-LEIS) are used to probe how the cluster-surface interaction changes due to heat treatment. Results show that bare Ru3 supported on SiO2 remain on the surface layer but agglomerates upon heating. Conversely, when supported on sputter-treated RF-TiO2, bare Ru3 is encapsulated by a layer of titania substrate material as-deposited. Ligated Ru3(CO)12 is also covered by a layer of titania when deposited onto sputter-treated RF-TiO2 but heat treatment is required to remove most of the ligands. TD-LEIS is used to directly measure the encapsulation of CVD Ru3(CO)12 clusters on sputter-treated RF-TiO2 and determine the substrate overlayer thickness. The overlayer was found to be 1-2 monolayers, which is thin enough for catalytic or photocatalytic reactions to occur without Ru being present in the outermost layer.

Graphene supported transition metal clusters are of great interest for potential applications, such as catalysis, due to their unique properties. In this work, a simple approach to deposit Au101(PPh3)21Cl5 (Au101NC) on reduced graphene oxide (rGO) via an ex situ method is presented. Reduction of graphene oxide at native pH (pH ≈ 2) to rGO was performed under aqueous hydrothermal conditions. Decoration of rGO sheets with controlled content of 5 wt% Au was accomplished using only pre-synthesised Au101NC and rGO as precursors and methanol as solvent. High resolution scanning transmission electron microscopy indicated that the cluster size did not change upon deposition with an average diameter of 1.4 ± 0.4 nm. It was determined that the rGO reduction method was crucial to avoid agglomeration, with rGO reduced at pH ≈ 11 resulting in agglomeration. X-ray photoelectron spectroscopy was used to confirm the deposition of Au101NCs and show the presence of triphenyl phosphine ligands, which together with attenuated total reflectance Fourier transform infrared spectroscopy, advocates that the deposition of Au101NCs onto the surface of rGO was facilitated via non-covalent interactions with the phenyl groups of the ligands. Inductively coupled plasma mass spectrometry and thermogravimetric analysis were used to determine the gold loading and both agree with a gold loading of ca. 4.8–5 wt%. The presented simple and mild strategy demonstrates that good compatibility between size-specific phosphine protected gold clusters and rGO can prevent aggregation of the metal clusters. This work contributes towards producing an agglomeration-free synthesis of size-specific ligated gold clusters on rGO that could have wide range of applications.

The photocatalytic properties of titania (TiO2) have prompted research utilising its useful ability to convert solar energy into electron–hole pairs to drive novel chemistry. The aim of the present work is to examine the properties required for a synthetic method capable of producing thin TiO2 films, with well defined, easily modifiable characteristics. Presented here is a method of synthesis of TiO2 nanoparticulate thin films generated using RF plasma capable of homogenous depositions with known elemental composition and modifiable properties at a far lower cost than single-crystal TiO2. Multiple depositions regimes were examined for their effect on overall chemical composition and to minimise the unwanted contaminant, carbon, from the final film. The resulting TiO2 films can be easily modified through heating to further induce defects and change the electronic structure, crystallinity, surface morphology and roughness of the deposited thin film.

Renewable energy has become a mandatory pursuit towards solving the world's reliance on fossil fuels, an environmentally damaging and finite resource. Many renewable energy sources are intermittent in nature, so storage must be incorporated as part of any energy solution. Lithium-ion batteries (LIBs) now represent the fastest growing energy storage system compared to all other technologies. Thus increasing their energy storage capacity is the subject of ongoing research for inclusion in many modern applications and the near exclusive reliance on graphitic anodes represents a limiting factor for LIBs. While silicon-based anodes have an energy capacity that is up to 11 times greater than their graphite-based equivalents, they have yet to be fully commercialized. This is due to silicon-based anodes suffering from unacceptable electrochemical and mechanical degradation as silicon undergoes a large volume expansion (≈400%) during charge/discharge cycling. This review gives a comprehensive overview and understanding of pure thin-film silicon anodes using physical vapor and chemical vapor deposition (PVD & CVD) and the factors affecting their electrochemical performance and cyclability. A deeper understanding of these factors will enable researchers to take appropriate steps towards improving the performance of LIBs which will ultimately result in the commercialization of silicon-based anodes for LIBs. Refereed/Peer-reviewed

The effect of thermal treatment on the structure and electrical/optical properties of vapor phase-polymerized poly(3,4-ethylenedioxythiophene):tosylate (PEDOT:Tos) and polypyrrole:tosylate (PPy:Tos) polymer films was investigated. Thermal treatment was applied postpolymerization but prior to washing the embedded oxidant layer out of the polymer film. Structural and chemical changes arising from the treatment were studied in the context of their conductive and electrochromic behavior. Spectroscopic analysis indicated a rise in the doping levels of both conductive polymers when exposed to thermal treatment. Additionally, an increase in the film thickness was recorded after the oxidant and other unbound species were removed from the polymer layer using an ethanol rinse. As such, a strong indication that polymerization continued even in the absence of (external) monomer vapor was present. This film thickness increase was most pronounced for PPy:Tos but also present in the PEDOT:Tos film. Heat-treated films exhibited enhanced cohesion, making them more robust and therefore increasing the viability for the material to be used in the optoelectronics area. This robustness, due to additional (cross-linking) oligomer growth, came at the expense of lower conductivity relative to their untreated counterparts. Refereed/Peer-reviewed

Silicon is a leading candidate material to replace carbon/graphite, the commonly used anode material in lithium-ion batteries (LIBs), because it has an 11 times higher theoretical specific capacity. However, silicon anodes have two main issues, low electronic conductivity and large volume expansion during cycling, and these issues present challenges in the manufacture of mechanically stable high-electrochemical-performance Si electrodes. Physical vapor deposition (PVD) is an alternative fabrication process that can produce binderless compact Si thin films suitable for microbatteries and thin flexible devices. Despite numerous studies exploring the use of vacuum-based PVD silicon films, no definitive information has been recorded correlating how changes in process parameters affect the properties of the resulting deposited films and how this influences anode performance in Li-ion batteries. In this work, process parameters (i.e., deposition power and gas working pressure) were altered for various Si film deposition trials. Electronic resistivity, electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV), residual film stress, X-ray diffraction (XRD), Raman spectroscopy, Fourier transform infrared (FTIR) spectroscopy, and X-ray photoelectron spectroscopy (XPS) measurements were performed for a thorough physico/chemico analysis of the various films. This information was used to interpret the differences in discharge capacity and capacity retention obtained from the various Si anodes using galvanostatic charge/discharge cycling from assembled coin cells. CV measurements were used to corroborate performance outcomes, as well as to calculate Li-ion diffusion coefficients Refereed/Peer-reviewed

Silicon is touted as a replacement for the commercially utilized carbon anode in lithium ion batteries. However, two drawbacks have hindered its use: low electronic conductivity and significant volume changes during lithiation/delithiation. Numerous studies have examined ways to improve silicon thin films with doped and reactive (i.e., oxidized, nitrated, and hydrogenated) forms summarized herein. Factors affecting electrochemical performance and cycling stability are compared against pure silicon, with the two alternatives generally showing better results. Most of the improvements for doped silicon have been attributed to higher electronic conductivity. Treatment gases such as: oxygen, nitrogen, and hydrogen, have been used to produce reactive silicon films. For oxidized silicon reaction products (i.e., lithium silicate, lithiated silicon, and lithium oxide) during cycling were found to serve as a buffer layer and/or matrix, helping to negate volume changes during charge/discharge. Improvements in nitrated silicon films were attributed to large lithiation capacity, high lithium ion conductivity, and mechanical stability. The improvement in cyclability performance for hydrogenated silicon films has yet to be fully developed and further systematic investigations are warranted Refereed/Peer-reviewed

An expert consensus panel convened by the Italian Association for Inherited and Familial Gastrointestinal Tumors (Associazione Italiana per lo Studio della Familiarita ed Ereditarieta dei Tumori Gastrointestinali, AIFEG) reviewed the literature and agreed on a number of position statements regarding the definition and management of polyposis coli without an identified pathogenic mutation on the APC or MUTYH genes, defined in the document as NAMP (non-APC/MUTYH polyposis).

Refereed/Peer-reviewed The use of silicon as a replacement for graphite, the commonly utilised anode material, would help increase the energy density of lithium-ion batteries, as it has a significant specific capacity of 4200 mAh/g compared to only 372 mAh/g for graphite. However, the high electronic resistivity and low mechanical stability of silicon have hindered its commercial uptake. In this contribution, we have employed a multifaceted approach in order to enhance the capacity retention of pure silicon anodes. The effect of adding 5 vol. % vinylene carbonates to a standard electrolyte has been examined with respect to the performance of physical vapour deposited pure Si thin films. Changes in battery cycling parameters (i.e., lower and upper cut-off voltages and depth of discharge were examined using charge/discharge cycling, cyclic voltammetry, and electrochemical impedance spectroscopy, indicating that cycling stability and electrochemical performance of the anodes were heavily influenced by these changes. The effect of each procedure (i.e., electrolyte additive and battery cycling protocol) on the initial discharge capacity, initial coulombic efficiency, initial irreversible capacity, capacity retention, and the lithium-ion diffusion coefficient into the silicon anode was examined. The Si film with optimised: deposition conditions, electrolyte additives, and battery testing protocol had a discharge capacity of 1740 mAh/g and capacity retention of 92 % at a charge/discharge rate of C/2 after 1000 cycles.

Silicon has been considered a good candidate for replacing the commonly used carbon anodes for lithium-ion batteries (LIBs) due to its high specific capacity, which can be up to 11 times higher than that of carbon. However, the desirable advantage that silicon brings to battery performance is currently overshadowed by its stress-induced performance loss and high electronic resistivity. The induced stress arises from two sources, namely, the deposition process (i.e., residual stress) during fabrication and the volume expansion (i.e., mechanical stress) associated with the lithiation/delithiation process. Of the two, residual stress has largely been ignored, underestimated, or considered to have a negligible effect without any rigorous evidence being put forward. In this contribution, we produced silicon thin films having a wide range of residual stress and resistivity using a physical vapor deposition technique, magnetron sputtering.Three pairs of silicon thin-film anodes were utilized to study the effect of residual stress on the electrochemical and cyclability performance as anodes for LIBs. Each set consisted of a pair of films having essentially the same resistivity, density, thickness, and oxidation amount but distinctly different residual stresses. The comparison was evaluated by conducting charge/discharge cycling and cyclic voltammetry (CV) experiments. In contrast to the fixed belief within the literature, higher compressive residual-stress films showed better electrochemical and cycle performance compared to lower residual-stress films. The results, herein, present an informed understanding of the role that residual stress plays, which will help researchers improve the development of silicon-based thin-film anodes. Refereed/Peer-reviewed

Aluminium, first surface, plastic mirrors have been developed to be used as heliostats in concentrated solar power stations. The Al reflective layer, the adhesion of the reflective layer to the polycarbonate (PC) substrate and the protective over-coat have all been optimized in order to achieve a highly reflective, robust and durable light-weight mirror. The Al layers were deposited by means of magnetron sputtering and the change in reflectance was investigated as a result of variations in the sputtering conditions. The influence of the substrate cleaning process and the addition of an interfacial seed layer on the adhesion of the reflective layer were also systematically studied. A thick sputtered SiO2 film and a dip-coated transparent hard-coat resin were examined as protective coatings against weathering tests. All prepared samples were characterised using, adhesion and abrasion tests, spectrophotometry, nano-scratch, salt-spray tests and both accelerated and outdoor weathering.The optimal three-layer stack was found to be 15 nm of SiO2 as an adhesive layer, 80 nm of Al as the reflector and 4.5 μm dip-coated, hard-coat resin as the protective layer. The three-layer stack plastic mirror gave an overall total solar weighted specular reflectance of ≈88% which was maintained even after aggressive abrasion tests such as Bayer and Steel Wool, 40 days within a salt-spray chamber and after 5 months under accelerated weathering. Refereed/Peer-reviewed

Syndromes caused by copy number variations are described as reciprocal when they result from deletions or duplications of the same chromosomal region. When comparing the phenotypes of these syndromes, various clinical features could be described as reversed, probably due to the opposite effect of these imbalances on the expression of genes located at this locus. The NFIX gene codes for a transcription factor implicated in neurogenesis and chondrocyte differentiation. Microdeletions and loss of function variants of NFIX are responsible for Sotos syndrome-2 (also described as Malan syndrome), a syndromic form of intellectual disability associated with overgrowth and macrocephaly. Here, we report a cohort of nine patients harboring microduplications encompassing NFIX. These patients exhibit variable intellectual disability, short stature and small head circumference, which can be described as a reversed Sotos syndrome-2 phenotype. Strikingly, such a reversed phenotype has already been described in patients harboring microduplications encompassing NSD1, the gene whose deletions and loss-of-function variants are responsible for classical Sotos syndrome. Even though the type/contre-type concept has been criticized, this model seems to give a plausible explanation for the pathogenicity of 19p13 microduplications, and the common phenotype observed in our cohort.

Small Ru clusters are efficient catalysts for chemical reactions such as CO hydrogenation. In this study 3-atom Ru

Graphene supported transition metal clusters are of great interest for potential applications, such as catalysis, due to their unique properties. In this work, a simple approach to deposit Au

Inherently conducting polymers (ICPs) combine the electrical properties of metals and semiconductors with a polymer's ability to flex and/or stretch. In general, polymers are relatively simple to synthesise, however, ICPs themselves have had limited uptake in consumer devices. This lack of uptake is in part related to the insolubility of many ICPs in common industrial solvents, and hence methods to manufacture them in a usable form have been problematic. Vapour phase polymerisation (VPP) is one method that provides a convenient route to producing thin films of both soluble and insoluble ICPs, and nanocomposites thereof. In this critical review the VPP process will be discussed from the fundamental viewpoint of the proposed polymerisation mechanism and the parameters affecting polymer growth for a range of different monomers (thiophene, 3-hexylthiophene, pyrrole, 3,4-ethylenedioxythiophene, etc.). Looking forward into the future, new areas of polymer design and fabrication using VPP will be discussed, such as the enhancement of ICPs through additives, and next generation device fabrication based upon VPP ICPs. Refereed/Peer-reviewed