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Over the last decade, the CO2 reduction reaction (CO2RR) has been increasingly exploited for the synthesis of high‐value raw materials in gaseous or liquid form, although no examples of CO2 fixation in nanoparticle systems have been demonstrated. Herein, CO2 fixation into solid nanomaterials by laser synthesis and processing of gold colloids in water, traditionally considered a green approach leading to ligand‐free nanoparticles without the formation of by‐products, is reported. If carbon monoxide‐rich gold nanoparticles are observable even after synthesis in deionized water, the presence of CO2 derivatives in alkaline water environment leads to C2 and C3 coupling with the production of carboxylic acids as a typical CO2RR fingerprint. While laser processing of preformed gold colloids is selective for C2 coupling, both C2 and C3 coupling to lactic acid are observed during pulsed laser ablation of a gold target. In the latter case, it is demonstrated that it is possible to synthesize photoluminescent organometallic nanocomposites in the blue spectral region with a quantum yield of about 20% under adequate experimental conditions. In this research, new pathways are offered to be explored in energetics, photonics, catalysis, and synthesis at the nanoscale. [ABSTRACT FROM AUTHOR]

The application of a DC current allows fast (few minutes) Ag+ → Na+ ion exchange in soda–lime–silicate (SLS) glass. The effect of processing parameters, electric current, and treating time is studied on both air and tin sides of SLS float glass, and non‐Fickian diffusion is revealed. It is shown that ion exchange kinetics are similar on both sides and the tempering process results in similar mechanical properties (crack formation probability after Vickers indentation, hardness, and Young's modulus). However, the structure/microstructure of the tin and air sides is hugely different. In particular, clear silver nanoclustering takes place on the tin side, resulting in ≈8 nm metallic particles in the vicinity of the surface. The formation of nanoparticles is also coupled with a deep structural reorganization of the amorphous network and the Qn units. The nanoparticles' size decreases moving from the surface to the interior of the glass. Silver nanoparticles are also detected on the air side, although their density and size are largely reduced. Whereas the mechanical properties measured on the air and tin side are similar, significative differences are observed in terms of optical properties. [ABSTRACT FROM AUTHOR]

The article "Correction to 'Pulsed-Laser-Driven CO2 Reduction Reaction for the Control of the Photoluminescence Quantum Yield of Organometallic Gold Nanocomposites'" in Small Science addresses errors in the Supporting Information section related to the Pulsed Laser Ablation process and ion chromatography. The correction clarifies the procedures for the PLAL and fragmentation processes, as well as the average TC values for the samples. The authors, a diverse group of researchers, apologize for the inaccuracies in the original text. [Extracted from the article]

Basalts are among the most abundant igneous rocks on Earth. Originated from the rapid cooling of magma erupted by volcanoes, they are increasingly used as raw materials in glass and ceramic technology due to their unique physico‐chemical properties. The characteristics of basalts, like the glass transition temperature, are strongly controlled by their structure, which is a function of composition. Therefore, the investigation of the interplay between the intimate structure and the mechanical and physical properties of basalt glasses is of paramount importance in view of their industrial exploitation. Here, we present a Raman study of a set of synthetic‐basalt glasses in which the occurrence of small chemical variations appreciably affects their glass transition temperature. We analyzed the Raman spectra focusing on both the spectral regions of the so‐called nonbridging oxygens and of the boson peak. We show the existence of a scaling law for the boson peak of four synthetic‐basalt glasses, and we infer from its breakdown the occurrence of a deep reorganization of the glass structure resulting from the Na–K replacement in the network, despite small variations of the other major elements. [ABSTRACT FROM AUTHOR]

Detailed crystallographic information provided by X‐ray diffraction (XRD) is complementary to molecular information provided by Raman spectroscopy. Accordingly, the combined use of these techniques allows the identification of an unknown compound without ambiguity. However, a full combination of Raman and XRD results requires an appropriate and reliable reference database with complete information. This is already available for XRD. The main objective of this paper is to introduce and describe the recently developed Raman Open Database (ROD, http://solsa.crystallography.net/rod). It comprises a collection of high‐quality uncorrected Raman spectra. The novelty of this database is its interconnectedness with other open databases like the Crystallography Open Database (http://www.crystallography.net/cod and Theoretical Crystallography Open Database (http://www.crystallography.net/tcod/). The syntax adopted to format entries in the ROD is based on the worldwide recognized and used CIF format, which offers a simple way for data exchange, writing and description. ROD also uses JCAMP‐DX files as an alternative format for submitted spectra. JCAMP‐DX files are compatible to varying degrees with most commercial Raman software and can be read and edited using standard text editors. [ABSTRACT FROM AUTHOR]

Abstract: The identification of mineralogical phases in drill cores is one of the most challenging tasks in the mining activity in view of an efficient metal extraction. This process requires the analytical characterization of large volumes of material to obtain a complete set of data in a minimum of time. None of the commonly used methods in mineralogical analyses, such as IR‐based techniques, X‐rays fluorescence, and hyperspectral imaging, is capable to provide a fully satisfactory response for several reasons, the main one being the complexity of the ores. Moreover, the characterization is often conducted in remote laboratories and only on selected samples to limit the time waste. A possible alternative solution requires a multianalytical approach exploiting on‐field techniques. This strategy is currently being developed within SOLSA, a joint EU H2020 project, and consists of an automatic expert system coupling sonic drilling, imaging, profilometer, hyperspectral cameras, and a combination of Raman spectroscopy, X‐rays fluorescence, and X‐rays diffraction. In this work, the principles on which this cooperative approach is based are discussed, with application to two specific test samples, showing the potential and novelty of the method. In particular, a case is considered in which the sample characterization by the separate use of a single technique fails, whereas the combination of the three analyses (Raman spectroscopy, X‐rays fluorescence, and X‐rays diffraction) works even if the system is very complex. [ABSTRACT FROM AUTHOR]

In this work the room temperature electrical conductivity of Si(B) OC glasses made via polymer pyrolysis at 1200°C and 1400°C (maximum temperature) and having different amount of boron was measured. When B content is increased from zero (pure Si OC glass) up to B/Si=0.5 the electrical conductivity increases in 2 orders of magnitude from 4.09±0.64×10−5 up to 2.93±1.91×10−3 with a corresponding decrease in the activation energy from about 1.08 to 0.51 eV. This results shows for the first time that the electrical conductivity of Si-based polymer-derived ceramics can be controlled by the amount of the doping element. The structure of the Si(B) OC glasses has been studied with different techniques including FT- IR, XRD and Raman spectroscopy. The Raman study indicates that B partially substitutes C into the sp2 C planes of the free carbon phase forming trigonal BC3 units. Accordingly, the evolution of the electrical properties with the B content has been correlated with the corresponding structural evolution and a hypothesis is presented to rationalize the role of boron on the electrical conductivity of Si OBC glasses. [ABSTRACT FROM AUTHOR]

In this study, we investigate the effects of electric field-assisted ion exchange ( EF- IE) on potassium for sodium ion exchanges of soda borosilicate and soda lime silicate glasses. The results show that applying an electric field (E-field) with the intensity of 1000 V cm−1 for few minutes produces an exchanged layer with a thickness comparable to the conventional chemical strengthening for 4 hours. There is a critical E-field that increases the mobility and, therefore, the diffusion coefficient of the potassium ions in the glasses. The increase is, perhaps, related to the evolution of the glass structure due to the penetration of potassium ions under an E-field. Vickers indentations showed that strong compression is generated in the glass by EF- IE; however, the bending strength improvement is limited because of the presence of large surface defects and the stress distribution inhomogeneity. [ABSTRACT FROM AUTHOR]

Millimetric Mn-doped enstatite (MgSiO3) crystals have been grown by slow cooling in MoO3, V2O5, and Li2CO3 flux. Six starting mixture with different amount of manganese were slowly cooled from 1350 °C, 1050 °C and 950 °C down to 750 °C, 650 °C and 600 °C respectively. The enstatite crystals were characterized by X-ray powder diffraction (XRPD) and scanning electron microscopy with energy-dispersive spectrometry (SEM/EDS). Mn-doped enstatite crystals were reddish in color, euhedral and elongate parallel to c-axis. The largest enstatite crystal obtained is 8.5 mm in length. The effects of growth parameters on yield and size of crystals were studied. Variations observed in crystal size were attributed to the amount of Mn doping. Further characterizations by μ-Raman spectroscopy (μ-R) and cathodoluminescence (CL) allowed to study the effect of Mn doping on some chemical/physical characteristics of the enstatite and to assess its potential in advanced technological applications. [ABSTRACT FROM AUTHOR]

The vibrational dynamics of a new class of cross-linked polymers obtained from both native and modified cyclodextrin, referred to as cyclodextrin nanosponges, is here investigated. The main purpose is to spot the structure of these materials at molecular level unlikely to be characterized by diffraction methods due to the low or null degree of crystallinity. The analysis of the spectral features of the vibrational bands observed between 1650 and 1800 cm−1 in both Raman and infrared spectra, and assigned to the carbonyl stretching modes of the polymeric network, is performed by using band deconvolution procedures. At the same time, a detailed inspection of the low-wavenumber vibrational dynamics of these polymers is carried out, focusing on the modifications occurring on the so-called boson peak. The simultaneous analysis of different wavenumber ranges in Raman and infrared spectra of cyclodextrin nanosponges allows us to develop a reliable strategy for exploring both the cross-linking degree and the elastic properties of these innovative materials. The overall results give a complete characterization of the structural and dynamical properties of the system, in turn strictly connected to the entrapment/transport ability of these polymeric matrices. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Some gemstones (diamonds, coloured stones or assembled gems) found in the jewellery commerce, when observed by an optical microscopy or even at naked eye, exhibit unusual characteristics, such as inclusions incorporated at different depths. The investigation by confocal Raman micro-spectroscopy allowed identification of a blue sapphire and of nanocrystalline anatase in the same surface region of a cut and polished diamond. Moreover, hematite (α-Fe2O3) inclusions of rectangular shape, embedded at different depths, ranging from a few microns to some tens of microns beneath the gemstone surface, were identified in the coloured stones. Finally, a detailed study of an assembled gem evidenced spectral features that can be put in relation with its fabrication process. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]