Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Phase transition induced strain in ZnO under high pressure.

ABSTRACT: Under high pressure, the phase transition mechanism and mechanical property of material are supposed to be largely associated with the transformation induced elastic strain. However, the experimental evidences for such strain are scanty. The elastic and plastic properties of ZnO, a leading material for applications in chemical sensor, catalyst, and optical thin coatings, were determined using in situ high pressure synchrotron axial and radial x-ray diffraction. The abnormal elastic behaviors of selected lattice planes of ZnO during phase transition revealed the existence of internal elastic strain, which arise from the lattice misfit between wurtzite and rocksalt phase. Furthermore, the strength decrease of ZnO during phase transition under non-hydrostatic pressure was observed and could be attributed to such internal elastic strain, unveiling the relationship between pressure induced internal strain and mechanical property of material. These findings are of fundamental importance to understanding the mechanism of phase transition and the properties of materials under pressure.

SUBMITTER: Yan X

PROVIDER: S-EPMC4865855 | biostudies-other | 2016 May

REPOSITORIES: biostudies-other

ACCESS DATA

Json Xml

Similar Datasets

Structural Phase Transition of ThC Under High Pressure.

Project description:Thorium monocarbide (ThC) as a potential fuel for next generation nuclear reactor has been subjected to its structural stability investigation under high pressure, and so far no one reported the observation of structure phase transition induced by pressure. Here, utilizing the synchrotron X-ray diffraction technique, we for the first time, experimentally revealed the phase transition of ThC from B1 to P4/nmm at pressure of ~58 GPa at ambient temperature. A volume collapse of 10.2% was estimated during the phase transition. A modulus of 147 GPa for ThC at ambient pressure was obtained and the stoichiometry was attributed to the discrepancy of this value to the previous reports.

| S-EPMC5428025 | biostudies-literature

Pressure-induced phase transition of 1,5-diamino-1<i>H</i>-tetrazole (DAT) under high pressure.

Project description:Nitrogen-rich energetic materials have attracted certain interest as promising high energy density materials (HEDMs) in recent years. Pure N2 and nitrogen-based molecular crystals are ideal HEDMs that would polymerize under high pressure, as reported in previous literature. We selected a 1,5-diamino-1H-tetrazole (DAT) crystal, which has two kinds of molecular structures and hydrogen bonds, to study under high pressure by spectroscopy and diffraction due to its high nitrogen percentage and low sensitivities. Pressure-induced structure transitions occur at pressures of 2.3-6.6 GPa, ∼8.5 GPa, and ∼17.7 GPa. The phase transition at 2.3-6.6 GPa is related to the rotation of NH2, and the latter two transitions are caused by both the rotation of NH2 and the distortion of the heterocycle. Significantly, the reconstitution of the hydrogen bond may induce the rotation/distortion of the NH2/heterocycle in the second phase transition. There is no evidence showing a transformation between the two molecular structures in the whole pressure range studied. Our investigation uncovers the phase transition mechanism of DAT under pressure, which will help to find targeted HEDMs.

| S-EPMC9056306 | biostudies-literature

Five-dimensional visualization of phase transition in BiNiO3 under high pressure.

Project description:Colossal negative thermal expansion was recently discovered in BiNiO3 associated with a low density to high density phase transition under high pressure. The varying proportion of co-existing phases plays a key role in the macroscopic behavior of this material. Here, we utilize a recently developed X-ray Absorption Near Edge Spectroscopy Tomography method and resolve the mixture of high/low pressure phases as a function of pressure at tens of nanometer resolution taking advantage of the charge transfer during the transition. This five-dimensional (X, Y, Z, energy, and pressure) visualization of the phase boundary provides a high resolution method to study the interface dynamics of high/low pressure phase.

| S-EPMC3977758 | biostudies-other

Structural evolution and phase transition mechanism of [Formula: see text] under high pressure.

Project description:[Formula: see text] is a layered transition-metal dichalcogenide (TMD) with outstanding electronic and optical properties, which is widely used in field-effect transistor (FET). Here the structural evolution and phase transition of [Formula: see text] under high pressure are systematically studied by CALYPSO structural search method and first-principles calculations. The structural evolutions of [Formula: see text] show that the ground state structure under ambient pressure is the experimentally observed P6[Formula: see text]/mmc phase, which transfers to R3m phase at 1.9 GPa. The trigonal R3m phase of [Formula: see text] is stable up to 72.1 GPa, then, it transforms into a new P6[Formula: see text]/mmc phase with different atomic coordinates of Se atoms. This phase is extremely robust under ultrahigh pressure and finally changes to another trigonal R-3m phase under 491.1 GPa. The elastic constants and phonon dispersion curves indicate that the ambient pressure phase and three new high-pressure phases are all stable. The electronic band structure and projected density of states analyses reveal a pressure induced semiconducting to metallic transition under 72.1 GPa. These results offer a detailed structural evolution and phase diagram of [Formula: see text] under high pressure, which may also provide insights for exploration other TMDs under ultrahigh pressure.

| S-EPMC8586237 | biostudies-literature

Ab initio investigation of CaO-ZnO alloys under high pressure.

Project description:Ca(x)Zn(1-x)O alloys are potential candidates to achieve wide band-gap, which might significantly promote the band gap engineering and heterojunction design. We performed a crystal structure search for CaO-ZnO system under pressure, using an ab initio evolutionary algorithm implemented in the USPEX code. Four stable ordered Ca(x)Zn(1-x)O structures are found in the pressure range of 8.7-60?GPa. We further constructed the pressure vs. composition phase diagram of CaO-ZnO alloys based on the detailed enthalpy calculations. With the increase in Ca concentration, the CaO-ZnO alloy first undergoes a hexagonal to monoclinic transition, and then transforms back to a hexagonal phase. At Above 9?GPa, there is no cubic structure in the alloys, in contrast to the insostructural components (B1-B1). The band gap of the Ca(x)Zn(1-x)O alloy shows an almost linear increase as a function of the Ca concentration. We also investigated the variation regularity of the band gap under pressure.

| S-EPMC4505315 | biostudies-literature

Miscibility and ordered structures of MgO-ZnO alloys under high pressure.

Project description:The MgxZn(1-x)O alloy system may provide an optically tunable family of wide band gap materials that can be used in various UV luminescences, absorption, lighting, and display applications. A systematic investigation of the MgO-ZnO system using ab initio evolutionary simulations shows that MgxZn(1-x)O alloys exist in ordered ground-state structures at pressures above about 6.5 GPa. Detailed enthalpy calculations for the most stable structures allowed us to construct the pressure-composition phase diagram. In the entire composition, no phase transition from wurzite to rock-salt takes place with increasing Mg content. We also found two different slops occur at near x = 0.75 of Eg-x curves for different pressures, and the band gaps of high pressure ground-state MgxZn(1-x)O alloys at the Mg concentration of x > 0.75 increase more rapidly than x < 0.75.

| S-EPMC4104395 | biostudies-literature

Peierls distortion mediated reversible phase transition in GeTe under pressure.

Project description:With the advent of big synchrotron facilities around the world, pressure is now routinely placed to design a new material or manipulate the properties of materials. In GeTe, an important phase-change material that utilizes the property contrast between the crystalline and amorphous states for data storage, we observed a reversible phase transition of rhombohedral ? rocksalt ? orthorhombic ? monoclinic coupled with a semiconductor ? metal interconversion under pressure on the basis of ab initio molecular dynamics simulations. This interesting reversible phase transition under pressure is believed to be mediated by Peierls distortion in GeTe. Our results suggest a unique way to understand the reversible phase transition and hence the resistance switching that is crucial to the applications of phase-change materials in nonvolatile memory. The present finding can also be expanded to other IV-VI semiconductors.

| S-EPMC3341046 | biostudies-literature

Critical scattering and incommensurate phase transition in antiferroelectric PbZrO3 under pressure.

Project description:Antiferroelectric lead zirconate is the key ingredient in modern ferroelectric and piezoelectric functional solid solutions. By itself it offers opportunities in new-type non-volatile memory and energy storage applications. A highly useful and scientifically puzzling feature of this material is the competition between the ferro- and antiferroelectric phases due to their energetic proximity, which leads to a challenge in understanding of the critical phenomena driving the formation of the antiferroelectric structure. We show that application of hydrostatic pressure drastically changes the character of critical lattice dynamics and enables the soft-mode-driven incommensurate phase transition sequence in lead zirconate. In addition to the long known cubic and antiferroelectric phases we identify the new non-modulated phase serving as a bridge between the cubic and the incommensurate phases. The pressure effect on ferroelectric and incommensurate critical dynamics shows that lead zirconate is not a single-instability-driven system.

| S-EPMC5278376 | biostudies-other

Structural phase transitions in Bi2Se3 under high pressure.

Project description:Raman spectroscopy and angle dispersive X-ray diffraction (XRD) experiments of bismuth selenide (Bi2Se3) have been carried out to pressures of 35.6 and 81.2?GPa, respectively, to explore its pressure-induced phase transformation. The experiments indicate that a progressive structural evolution occurs from an ambient rhombohedra phase (Space group (SG): R-3m) to monoclinic phase (SG: C2/m) and eventually to a high pressure body-centered tetragonal phase (SG: I4/mmm). Evidenced by our XRD data up to 81.2?GPa, the Bi2Se3 crystallizes into body-centered tetragonal structures rather than the recently reported disordered body-centered cubic (BCC) phase. Furthermore, first principles theoretical calculations favor the viewpoint that the I4/mmm phase Bi2Se3 can be stabilized under high pressure (>30?GPa). Remarkably, the Raman spectra of Bi2Se3 from this work (two independent runs) are still Raman active up to ~35?GPa. It is worthy to note that the disordered BCC phase at 27.8?GPa is not observed here. The remarkable difference in atomic radii of Bi and Se in Bi2Se3 may explain why Bi2Se3 shows different structural behavior than isocompounds Bi2Te3 and Sb2Te3.

| S-EPMC4629115 | biostudies-literature

Pressure-driven electronic phase transition in the high-pressure phase of nitrogen-rich 1H-tetrazoles.

Project description:High-energy-density materials (HEDMs) require new design rules collected from experimental and theoretical results and a proposed mechanism. One of the targeted systems is the nitrogen-rich compounds as precursors for possible polymeric nitrogen or its counterpart in a reasonable pressure range. 1H-tetrazole (CH2N4) with hydrogen bonds was studied under pressure by both diffraction and spectroscopy techniques. The observed crystal structure phase transition and hydrogen bond-assisted electronic structure anomaly were confirmed by first-principles calculation. The rearrangement of the hydrogen bonds under pressure elucidates the bonding interactions of the nitrogen-rich system in local 3D chemical environments, allowing the discovery and design of a feasible materials system to make new-generation high-energy materials.

| S-EPMC9034126 | biostudies-literature

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data