The search for new functional materials that combine high stability and efficiency with reasonable cost and ease of synthesis is critical for their use in renewable energy applications. Specifically in catalysis, nanoparticles, with their high surfaceto-volume ratio, can overcome the cost implications associated with otherwise having to use large amounts of noble metals. However, commercialized materials, i.e. catalytic nanoparticles deposited on oxide supports, often suffer from loss of activity due to coarsening and carbon deposition during operation. Exsolution has proven to be an interesting strategy to overcome such issues.Here the controlled emergence, or exsolution, of faceted iridium nanoparticles from a doped SrTiO3 perovskite is reported and their growth preliminary probed by in situ electron microscopy. Upon reduction of SrIr0.005Ti0.995O3 the generated nanoparticles show embedding into the oxide support, therefore preventing agglomeration and subsequent catalyst degradation. The advantages of this approach are the extremely low noble metal amount employed (~0.5% weight) and the catalytic activity reported during CO oxidation tests, where the performance of the exsolved SrIr0.005Ti0.995O3 is compared to the activity of a commercial catalyst with 1% loading (1% Ir/Al2O3). The high activity obtained with such low-doping shows the possibility for scaling up this new catalyst, reducing the high cost associated with iridium-based materials.Image analysis and calculations; XPS supplementary data; STEM-EDX maps of as-synthesised Ir0.5-STO (PDF)

The decomposition of Li-ion battery (LIB) electrolyte has been a well-known challenge that needs to be overcome. The most common electrolyte on lithium-ion batteries is LiPF6 which has all-balanced properties, while LiBF4 has been proven for its superior stability. These lithium salts are often dissolved in Ethylene Carbonate (EC) to form liquid electrolyte systems. In this work, we investigate the decomposition mechanism of EC in the presence of LiPF6, LiBF4, and their delithiated counterpart by means of first-principles density functional theory (DFT) calculations. We found that the energy barrier of decomposition on LiBF4 presence is 0.42 eV lower than on LiPF6 presence, also on BF4 - presence is 0.22 eV lower than PF6 - presence. This suggests that LiBF4 and BF4 - presence reduces EC stability more than LiPF6 and PF6 - anion. Moreover, the presence of Li+ ion increases the energy barrier of decomposition (about 0.79 eV on PF6 - case, 0.59 eV on BF4 - case) but decreases enthalpy change significantly (about 1.58 eV on PF6 - case, 1.43 eV on BF4 - case). This suggests that while the Li+ ion causes the decomposition to be slower, its presence destabilizes the EC more.