National Physical Laboratory

About: National Physical Laboratory is a facility organization based out in London, United Kingdom. It is known for research contribution in the topics: Dielectric & Thin film. The organization has 7615 authors who have published 13327 publications receiving 319381 citations.

A simple, low-cost CVD route to thin films of BiFeO3 for efficient water photo-oxidation

Abstract: A novel method for preparation of BiFeO3 films via a simple solution-based CVD method is reported using for the first time a single-source heterobimetallic precursor [CpFe(CO)2BiCl2]. BiFeO3 films display ferroelectric and ferromagnetic ordering at room temperature and possess direct band-gaps between 2.0 and 2.2 eV. Photocatalytic testing for water oxidation revealed high activities under UVA (365 nm) and simulated solar irradiation, superior to that exhibited by a commercial standard (Pilkington Activ® TiO2 film) resulting in an apparent quantum yield of ∼24%.

Cordierite glass-ceramics-effect of TiO2 and ZrO2 content on phase sequence during heat treatment

Abstract: A series of glasses of stoichiometric composition with varying proportions of TiO2 and/or ZrO2 as nucleating agent have been studied to examine the effect of nucleation addition on the sequence of crystallization and transformation to the stable phase, cordierite. It is shown that TiO2 is the most effective nucleating agent and that if large amounts of ZrO2 are substituted for TiO2 cristobalite forms as an intermediate phase and is associated with rapid volume changes and consequently with weak porous products. Substitution of ZrO2 for TiO2 also causes other changes in phase development, especially in the relative proportions of β-quartz solid solution and magnesian petalite produced during the early stages of crystallization. The use of a combination of experimental techniques (dilatometry, DTA, X-ray diffraction and electron microscopy) has proved most effective in studying phase development and the relationship between processing characteristics and composition.