Search

Reverse water-gas shift (RWGS) operation at lower temperatures has multiple advantages such as use of low-cost materials and improvement of thermal efficiency. This report demonstrates the enhancement of CO selectivity by Au addition and clarifies the relationship between the enhanced CO selectivity and the density of state (DOS) in the vicinity of the Fermi level (Ef)., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

The electronic, magnetic and crystal structures of layered perovskite oxide LaSr 3 Fe 3 O 10 (LSFO) in the Ruddlesden-Popper structure were studied from first principles using the density functional theory (DFT)+U pseudopotential (PP) method and a self-consistent constrained DFT technique (Hamada and Ohno 2019 J. Phys.: Condens. Matter 31 065501). Using this technique, the magnetic structure of LSFO was determined to be antiferromagnetic and an effective Hubbard on-site interaction parameter for Fe 3d electrons, U eff (Fe 3d )  =  6.08 eV was identified for LSFO. The DFT+U PP calculations of LSFO models using this U eff (Fe 3d ) value reproduced the experimentally observed metallic characteristics and crystal structure of LSFO, demonstrating the correct determination of the U eff (Fe 3d ) value of the large and complex LSFO material. The first-principles DFT+U calculation of large and complex strongly-correlated systems was enabled using the self-consistent constrained DFT technique.

Entry of direct methanol fuel cells into the market requires anode catalyst with stable activity. This paper presents a novel method for stabilizing the activity by immobilizing silica on the catalytic PtRu nanoparticles. Characterization was performed by STEM-EDX, XRD, and ICP. The silica-immobilized PtRu nanoparticles showed high and stable activity toward methanol oxidation. The activity was maintained for 1000 h in sulfuric acidic solution, while the activity of the catalyst with "bare" PtRu nanoparticles decayed after 100 h, showing high durability of the silica-immobilized PtRu nanoparticles catalyst in quasi-anodic acidic environment.