Platinum Metals Review - Volume 57, Issue 1, 2013

Although numerous materials can be utilised as emitters in electroluminescent devices, platinum complexes bearing organic ligands are among the most promising for use as highly efficient phosphorescent materials in which the singlet and triplet states can be simultaneously harvested for emission. This article aims to give an overview of recent progress in Pt phosphors featuring ingeniously designed ligands and to summarise their impressive performances when incorporated into organic light-emitting devices (OLEDs). Such materials show great promise for applications such as 3 at screen displays and low-energy solid-state lighting.

The photocatalytic activities of a series of titanium dioxide (TiO2) based nanoparticles, synthesised via flame spray pyrolysis (FSP), have been investigated and compared with the commercially available Evonik Aeroxide^® TiO2 P 25 (P 25). The effects of metal ions aluminium, tin and platinum, respectively, on the physical and chemical properties of the TiO2 nanoparticles are reported. The set of six samples were characterised by X-ray powder diffraction (XRD), transmission electron microscopy (TEM), inductively coupled plasma-mass spectrometry (ICP-MS) and ultraviolet-visible (UV-vis) diffuse reflectance spectroscopy. Specific surface areas were determined using nitrogen adsorption and desorption measurements. Subsequent photocatalytic studies of the degradation of methyl orange (MO) dye under UV irradiation demonstrated that addition of Al and Sn had a negative effect on catalytic performance, whereas the addition of ≤0.7 at% Pt to each sample enhanced photocatalytic activity. Most interestingly, the Pt-doped composite samples (TiO2-Sn/Pt and TiO2-Al/Pt) both showed a significantly higher rate of degradation of MO, when compared to P 25. All Pt-doped samples show an increased visible photon absorption capacity. The relationships between the physical and chemical characteristics are discussed in relation to photocatalytic performance.

The experimental data on the binary metallic iridium-rhenium system available to date are inconsistent. The present work summarises recent experimental data on the Ir-Re system with the aim of allowing the correct solidus parts of the equilibrium phase diagram to be constructed. The examination of data obtained by different synthetic methods and thermodynamic calculations has revealed that the maximum solid-phase solubilities at 2000°C of Re in Ir and Ir in Re are 20 at% and 68 at%, respectively. The binary phase diagram proposed in this paper serves as a reliable model for representing the available experimental data.