TY - INPR A1 - Miliūtė, Aistė ED - Bustamante, Joana ED - Karafiludis, Stephanos ED - Zöllner, Moritz ED - Eddah, Mustapha ED - Emmerling, Franziska ED - Mieller, Björn ED - George, Janine ED - Stawski, Tomasz T1 - Synthesis and phase purity of the negative thermal expansion material ZrV2O7 N2 - Synthesis of pure, homogeneous, and reproducible materials is key for the comprehensive understanding, design, and tailoring of material properties. In this study, we focus on the synthesis of ZrV2O7, a material known for its negative thermal expansion properties. We investigate the influence of solid-state and wet chemistry synthesis methods on the purity and homogeneity of ZrV2O7 samples. Our findings indicate that different synthesis methods significantly impact the material's characteristics. The solid-state reaction provided high-purity material through extended milling time and repeated calcination cycles, while the sol-gel reaction enabled a “near-atomic” level of mixing and, therefore, homogenous phase-pure ZrV2O7. We confirmed purity via X-ray diffraction and Raman spectroscopy, highlighting differences between phase-pure and multiphase ceramics. These analytical techniques allowed us to distinguish subtle differences in the structure of the material. Based on ab initio simulated phonon data, we were able to interpret the Raman spectra and visualise Raman active atom vibrations. We show that phase purity enables the unbiased characterisation of material properties such as negative thermal expansion. KW - NTE KW - Sol-gel KW - Solid-state KW - Ab-initio KW - XRD KW - Raman PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-613643 DO - https://doi.org/10.26434/chemrxiv-2024-d4sj9 SN - 2573-2293 VL - 2024 SP - 1 EP - 60 PB - American Chemical Society CY - Washington, D.C. AN - OPUS4-61364 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Miliūtė, Aistė T1 - Synthesis and phase purity of the negative thermal expansion material ZrV2O7 N2 - This repository contains computational and experimental data for the manuscript titled “Synthesis and phase purity of the negative thermal expansion material ZrV2O7”. KW - NTE KW - Sol-gel KW - Solid-state KW - Ab-initio KW - XRD KW - Raman PY - 2024 DO - https://doi.org/10.5281/zenodo.12688634 PB - Zenodo CY - Geneva AN - OPUS4-61360 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Stephan-Scherb, Christiane T1 - Novel insights into high temperature corrosion phenomena by advanced X-ray methods N2 - A variety of materials of technological interest change their properties through contact with reactive media. Solid-gas reactions lead to a variety of reaction products on the surfaces and internal interfaces. The observation of nucleation and growth processes in the environment where they occur (in situ) from a chemical-structural perspective is especially challenging for aggressive atmospheres. The talk presents innovative approaches to study corrosion mechanisms using advanced X-ray methods. Using energy dispersive X-ray diffraction and X-ray absorption spectroscopy in different tailor made environmental reaction chambers, valuable insights into high temperature oxidation and sulfidation processes were gained. Fe-based alloys were exposed to hot and reactive atmospheres containing gases like SO2, H2O and O2 at 650°C. During the gas exposure the tailor made reaction chambers were connected to a high energy diffraction end station at the synchrotron. The crystallization and growth of oxide and sulfide reaction products at the alloy surfaces were monitored by collecting full diffraction pattern every minute. Careful examination of shape and intensity of phase-specific reflections enabled to a detailed view on growth kinetics. These studies showed, oxides are the first phases occurring immediately after experimental start. As soon as reactive gas media enter the chamber, the conditions change and different reaction products, such as sulfides start to grow. A comparison of different gas environments applied, illustrated the differences in the type of reaction products. The in situ observation of high temperature material degradation by corrosion made it possible to study the contribution of phases, which are not stable at room temperature. For instance, wuestite (Fe1-xO), was frequently observed at high temperatures in humid gases on Fe with 2 wt.% and 9 wt.% chromium, but not at room temperature. The strength of the occurrence of this phase additionally explains why, despite a higher Cr content, ferritic alloys with 9 wt.% Cr in a challenging atmosphere prevent the intrinsic formation of protective layers. The in situ observations were supplemented by careful considerations of thermodynamic boundary conditions and detailed post characterization by classical metallographic analysis. Additionally, the structure and chemistry of the dominant oxide layers were evaluated using X-ray absorption near edge structure spectroscopy. The talk will give an overview about chances and challenges for studying high temperature corrosion phenomena by advanced X-ray methods. T2 - MRS Spring Meeting CT08.02.01 CY - Online Meeting DA - 18.04.2021 KW - XRD KW - Spectroscopy KW - Corrosion KW - High temperature KW - In-situ PY - 2021 AN - OPUS4-52486 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Miliūtė, Aistė T1 - How experimental and computational methods allow us to design negative thermal expansion materials N2 - Combined experimental and computational methods allow comprehensive understanding, design, and tailoring of material properties. We focus on a well-known negative thermal expansion (NTE) material, zirconium vanadate (ZrV2O7), and address synthesis, characterisation and validation of results with computational simulations. Experimental and computational X-ray diffraction and Raman spectroscopy data highlighted differences between phase-pure and multiphase ceramics. These techniques allowed us to distinguish subtle differences in the structure of the material. Based on ab initio simulated phonon data, unaffected by impurities or instrumental errors, we could interpret the Raman spectra and visualise Raman active atom vibrations. These computational models allowed better insight and further experimental improvement while high-quality experimental data granted the validation and improvement of computational simulation strategy. T2 - Application of Neutrons and Synchrotron Radiation in Engineering Materials Science CY - Hamburg, Germany DA - 23.03.2025 KW - NTE KW - Sol-gel KW - Ab initio KW - Raman KW - XRD PY - 2025 AN - OPUS4-62832 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Miliūtė, Aistė T1 - How experimental and computational methods allow us to design negative thermal expansion materials N2 - Combined experimental and computational methods allow comprehensive understanding, design, and tailoring of material properties. We focus on a wellknown negative thermal expansion (NTE) material, zirconium vanadate (ZrV2O7), and address synthesis, characterisation and validation of results with computational simulations. Experimental and computational X-ray diffraction and Raman spectroscopy data highlighted differences between phase-pure and multiphase ceramics. These techniques allowed us to distinguish subtle differences in the structure of the material. Based on ab initio simulated phonon data, unaffected by impurities or instrumental errors, we could interpret the Raman spectra and visualise Raman active atom vibrations. These computational models allowed better insight and further experimental improvement while high-quality experimental data granted the validation and improvement of computational simulation strategy. T2 - SALSA Make and Measure 2024 CY - Berlin, Germany DA - 11.09.2024 KW - NTE KW - Sol-gel KW - Ab initio KW - Raman KW - XRD PY - 2024 AN - OPUS4-61358 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -