A Sub-Microanalysis Approach in Chemical Characterisation of Gold Nanorods Formed by a Novel Polymer-Immobilised Gold Seeds Base

Gold nanorods (GNRs) have been fabricated by a novel polymer-immobilised seed mediated method using ultraviolet (UV) photoreduced gold-polymethylmethacrylate (Au–PMMA) nanocomposites as a seed platform and characterised at sub-micron scale regime with synchrotron-based techniques; near-edge X-ray absorption fine structure (NEXAFS) spectroscopy and X-ray fluorescence (XRF) mapping. In this report, it is shown that investigating polymer nanocomposites using combination of XRF mapping and NEXAFS spectromicroscopy can help to see the growth phenomenon from different perspective than conventional characterisation techniques. XRF maps are used to explore distribution of the constituent elements and showing how polymer matrix making stripe patterns along with regions where GNRs are formed. NEXAFS carbon (C) K-edge spectra have been taken at three different stages of synthesis: (1) on Au–PMMA nanocomposites before UV irradiation, (2) after gold nanoparticles formation, and (3) after GNRs formation. It reveals how polymer matrix has been degraded during GNRs formation and avoiding chemically or physically damage to polymer matrix is crucial to control the formation of GNRs

Low temperature synthesis of ZnSe nanoparticles

Synthesis of thioglycerol capped zinc selenide nanoparticles with a relatively narrow size distribution by a simple and inexpensive low temperature (~ 80 °C) wet chemical method is reported here. Main advantage of this method is the use of non-toxic precursors. The size of the nanoparticles can be varied easily by changing the concentration of the capping agent. The extracted nanoparticles remain stable under normal atmospheric conditions and can be redispersed in suitable solvents. The sharp absorption features obtained in the UV-Visible absorption spectra reveal the formation of monodispersed ZnSe nanoparticles. The nanoparticles were characterized using X-ray photoelectron spectroscopy, X-ray diffraction, UV-Visible absorption spectroscopy, photoluminescence and transmission electron microscopy

Pulse-plating of Mn-Cu-ZnO for supercapacitors: a study based on soft X-ray fluorescence and absorption microspectroscopy

This paper reports on the electrodeposition of Mn-Cu-ZnO for hybrid supercapacitors. This material exhibits a dual structure consisting of Mn-rich highly active, but poorly electronically conducting, grains, which are locked by a Cu-rich highly conductive network that also possesses some degree of charge-storage capacity. This work focuses on morphological, compositional, and chemical-state distributions with submicrometer lateral resolution. This information, which is crucial because doping distribution controls supercapacitor performance, has been obtained by combining electrochemical and in situ Raman measurements with synchrotron-based X-ray fluorescence and absorption microspectroscopy. Using a microfabricated thin-layer three-electrode microcell, we followed the morphochemical changes at different electrodeposition stages and found that pulse-plating allows the growth of Mn-and Cu-doped ZnO as self-organized structures with a consistent spatially stable composition distribution

Novel insight into bronze disease gained by synchrotron-based photoelectron spectromicroscopy, in support of electrochemical treatment strategies

A recent assessment (Giovannelli, G., D'Urzo, L., Maggiulli, G., Natali, S., Pagliara, C., Sgura, I. & Bozzini, B. 2010. Journal of Solid State Electrochemistry, 14: 479–94.) of the corrosion state of a late Bronze Age artefact (ca. 1100 BCE) exposed to a coastal environment, based on optical and scanning electron microscopies, X-ray fluorescence mapping, and X-ray diffractometry, led to recognition of bronze disease conditions essentially related to the presence of nantokite locked inside mesoscopic subsurface pits. The object was then treated successfully with a novel electrochemical approach specifically designed to allow penetration of the electric field into deep, screened pits. In order to further develop and optimize this promising approach by fine-tuning the capabilities of electrochemical control, more insight is required on the specific morphochemistry of the corrosion product scenario. To this end, here we report a space-dependent compositional and chemical-state analysis, performed with synchrotron-based scanning photoelectron microspectroscopy. The investigated object consists of a segregated cast bronze. The prevailing corrosion form is preferential attack of Sn-rich phases, accompanied by a synergistic type of Sn and Cu attack triggered by the peculiar type of decuprification taking place in a bronze disease framework and characterized by the formation of Sn(OH)Cl as a result of local HCl generation in the Cu corrosion process