Dec 09, 2011 Pyrochlore-structured materials are very important materials due to their structural and conducting properties. These properties can be further modified by changing processing conditions. In the present study, pyrochlore (Y2Ti2O7) is synthesized using high-energy ball milling. During various stages of ball milling, the ball-milled powder is taken for investigating the structural and thermal
Jan 01, 2011 The hexagonal phase produced by high-energy ball milling of RbNbWO 6 transforms back to the pyrochlore structure upon heating to 773 K in air. A similar phase was obtained by ball milling the mixture RbNbWO 6 + WO 3, but, in this case, the stoichiometric hexagonal tungsten bronze compound thus obtained remained stable up to 1273 K
Ball milling-induced pyrochlore-to-tungsten bronze phase transition in RbNbWO6 Janete E. Zorzi, Cintia L.G. de Amorim, Raquel Milani, and Carlos A. Figueroa Universidade de Caxias do Sul, 95070-560 Caxias do Sul–RS, Brazil Joa˜o A.H. da Jornada Inmetro, 25250-020 Xere m, Duque de Caxias–RJ, Brazil; and Universidade Federal do Rio Grande do Sul, Instituto de Fı sica, 91501-970 Porto
Based on the literature on ball milling of different oxide materials and from our present XRD results, we conclude that it is not possible to obtain the phase pure CaWO4 materials by ball-milling
Apr 18, 2002 Pyrochlore-free nano-sized (1−x)PMN–xPT (x=0, 0.10, 0.35) (PMN–PT) powders were synthesized from a mixture of the commercial oxides PbO, MgO, TiO 2 and Nb 2 O 5 by a high-energy ball milling process. The grain size estimated from XRD patterns for the three samples was about 10–30 nm. The high sinterability of the synthesized PMN and PMN–PT powders was evidenced by the fact
Jan 01, 2016 In this interesting article, the synthesis of nanocrystalline Gd₂Ti₂O₇ material by ball milling followed by annealing, characterization and its application are reported. The Rietveld structural refinement data confirm the cubic pyrochlore Gd₂Ti₂O7 phase with lattice parameter, a = 1.022(9) nm
Ball milling increases the surface area of the materials, leading to strongly improved activity for the generation of ˙OH radicals, but also generates surface defects in the materials. The defective sites act as electron traps, which depress the photocatalytic hydrogen evolution activity
In the present study, pyrochlore (Y2Ti2O7) is synthesized using high-energy ball milling. During various stages of ball milling, the ball-milled powder is taken for investigating the structural
planetary ball mill. This material was also charaterised using PXRD both for structure determination and thermoresponsive studies. The ball mill consisted of a stainless steel jar and this had implications on the final product, this is an observation which has never been explored before. This dissertation consists of
3 were selected as starting materials to make A sites in pyrochlore structure highly disordered, while keeping B sites unchangeable. By choosing five out of the six rare oxides with equimolar ratio, we successfully ... 2 by planetary ball milling for 10 h at 560 r/min. The ground powder mixtures were
prepared as starting materials. Samples were first crashed and mixed in stoichiometry. Then they are milled in a planetary ball mill for 12 hours with alcohol added as dispersant and lu-bricant. After milling procedure, the product was heated in a drying oven at 85 ∘C atmosphere to expel alcohol from sam-ple
The microstructural evolution of Dy2O3-TiO2 powder mixtures during ball milling and post-milled annealing was investigated using XRD, SEM, TEM, and DSC. At high ball-milling rotation speeds, the mixtures were fined, homogenized, nanocrystallized, and later completely amorphized, and the transformation of Dy2O3 from the cubic to the monoclinic crystal structure was observed
Jun 15, 2012 1. As the name suggests, the ball milling method consists of balls and a mill chamber. Therefore over all a ball mill contains a stainless steel container and many small iron, hardened steel, silicon carbide, or tungsten carbide balls are made to rotate inside a mill (drum). 2. The powder of a material is taken inside the steel container
pyrochlore structure were obtained by this mechano- chemical synthesis method [62]. Stoichiometric mixtures of the constituent oxides were milled in a planetary ball mill with a speed of 350 rpm. XRD results showed that chemical changes occurred in the powder mixtures after milling for 19 h, and single phase solid solutions were obtained
The selected pyrochlore compositions are synthesized by both sol gel and solid state processing, and how composite processing affects the microstructure will be discussed. Among the multiple composite processing approaches investigated, ball milling produces the
Nov 12, 2021 The as-synthesized LLZO-micro-powder had a particle size distribution with a d 50 value of 7.6 m, which was decreased to 2.7 m by ball milling. When 5 % wt pyrochlore nanopowder was added, the obtained d 50 value after ball milling was 5 m. In both cases, powders with agglomerated fine particles were obtained after milling
Dec 28, 2016 1. Introduction. High-energy ball milling has been widely used to prepare various types of materials, such as supersaturated solid solutions, metastable crystalline materials [], quasicrystal phases [], nanostructured materials [], and amorphous alloys [].The technology was initially used in place of blending and sintering at elevated temperatures to prepare ceramic-strengthened alloys [5,6]
