Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “Zn”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 145 records · Page 8
All sourcesNASA NTRSDOE OSTI
DOE OSTI2024

Atomically synergistic Zn-Cr catalyst for iso-stoichiometric co-conversion of ethane and CO2 to ethylene and CO

Abstract Developing atomically synergistic bifunctional catalysts relies on the creation of colocalized active atoms to facilitate distinct elementary steps in catalytic cycles. Herein, we show that the atomically-synergistic binuclear-site catalyst (ABC) consisting of $${{{{{\rm{Zn}}}}}}^{\delta+}$$ Zn δ + -O-Cr 6+ on zeolite SSZ-13 displays unique catalytic properties for iso-stoichiometric co-conversion of ethane and CO 2 . Ethylene selectivity and utilization of converted CO 2 can reach 100 % and 99.0% under 500 °C at ethane conversion of 9.6%, respectively. In-situ/ex-situ spectroscopic studies and DFT calculations reveal atomic synergies between acidic Zn and redox Cr sites. $${{{{{\rm{Zn}}}}}}^{\delta+}$$ Zn δ + ( $$0 \, < \, \delta \, < \, 2$$ 0 < δ < 2 ) sites facilitate β-C-H bond cleavage in ethane and the formation of Zn-H δ - hydride, thereby the enhanced basicity promotes CO 2 adsorption/activation and prevents ethane C-C bond scission. The redox Cr site accelerates CO 2 dissociation by replenishing lattice oxygen and facilitates H 2 O formation/desorption. This study presents the advantages of the ABC concept, paving the way for the rational design of novel advanced catalysts.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2022

Reactivity of Zn + aq in high-temperature water radiolysis

For this work, reactivity of transients involving Zn + in high-temperature water radiolysis has been studied in the temperature range of 25–300 °C. The reduced monovalent zinc species were generated from an electron transfer process between the hydrated electron and Zn 2+ ions using pulse radiolysis. The Zn + species can subsequently be oxidized by the radiolytically-produced oxidizing species: ˙OH, H 2 O 2 and ˙H. We find that the absorption of monovalent zinc is very sensitive to the pH of the medium. An absorption maximum at 306–311 nm is most pronounced at pH 7 and the signal then decreases in acidic media where the reducing electrons are competitively captured by protons. At pH values higher than 7, hydroxo-forms of Zn 2+ are created and the maximum of the absorption signal begins to shift to the red spectral region. We find that the optical spectrum of Zn + aq cannot be fully explained in terms of a charge-transfer to solvent (CTTS) process, which was previously proposed. Reaction rates of most of the recombination reactions investigated follow the empirical Arrhenius relationship at temperatures up to 200 °C and have been determined at higher temperatures for the first time. A bimolecular disproportionation reaction of Zn + aq is not observed under the conditions investigated.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2021

Electronic and optical properties of Zn-doped β-Ga 2 O 3 Czochralski single crystals

β-Ga 2 O 3 has several soluble deep acceptors that impart insulating behavior. In this study, we investigate Zn doping (0.25at.%) in bulk Czochralski and vertical gradient freeze β-Ga 2 O 3 . Representative crystals were assessed for orientation (electron backscatter diffraction and Raman spectroscopy), purity (glow discharge mass spectrometry and secondary ion mass spectrometry), optical properties (ultraviolet to near infrared absorption), and electrical properties (resistivity and current–voltage). Purity measurements indicate that Zn evaporation is insufficient to inhibit doping of Zn into β-Ga 2 O 3 . Hybrid functional calculations show Zn substitutes nearly equally on tetrahedral and octahedral sites, with less than ~0.1eV preference for the octahedral (Ga II ) site. Furthermore, calculations show that Zn Ga acts as a deep acceptor with trapping levels ~1.3 and ~0.9eV above the valence band for one and two holes, respectively. The solubility and electronic behavior of Zn dopants are consistent with measured concentrations >1×10 18 atoms/cm 3 and electrical measurements that show resistivity 10 11 –10 13 Ωcm, with no p-type conduction.

36 MATERIALS SCIENCE↗
DOE OSTI2023

Zn deficiency disrupts Cu and S homeostasis in Chlamydomonas resulting in over accumulation of Cu and Cysteine

Growth of Chlamydomonas reinhardtii in zinc (Zn) limited medium leads to disruption of copper (Cu) homeostasis, resulting in up to 40-fold Cu over-accumulation relative to its typical Cu quota. Here, we show that Chlamydomonas controls its Cu quota by balancing Cu import and export, which is disrupted in a Zn deficient cell, thus establishing a mechanistic connection between Cu and Zn homeostasis. Transcriptomics, proteomics and elemental profiling revealed that Zn-limited Chlamydomonas cells up-regulate a subset of genes encoding “first responder” proteins involved in sulfur (S) assimilation and consequently accumulate more intracellular S, which is incorporated into L-cysteine, γ-glutamylcysteine, and homocysteine. Most prominently, in the absence of Zn, free L-cysteine is increased ~80-fold, corresponding to ~2.8 × 10 9 molecules/cell. Interestingly, classic S-containing metal binding ligands like glutathione and phytochelatins do not increase. X-ray fluorescence microscopy showed foci of S accumulation in Zn-limited cells that co-localize with Cu, phosphorus and calcium, consistent with Cu-thiol complexes in the acidocalcisome, the site of Cu(I) accumulation. Notably, cells that have been previously starved for Cu do not accumulate S or Cys, causally connecting cysteine synthesis with Cu accumulation. We suggest that cysteine is an in vivo Cu(I) ligand, perhaps ancestral, that buffers cytosolic Cu.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2020

Controlling magnetic order, magnetic anisotropy, and band topology in the semimetals Sr(Mn 0.9 Cu 0.1 )Sb 2 and Sr(Mn 0.9 Zn 0.1 )Sb 2

Neutron diffraction and magnetic susceptibility studies show that orthorhombic single-crystals of topological semimetals Sr(Mn 0.9 Cu 0.1 ) Sb 2 and Sr(Mn 0.9 Zn 0.1 )Sb 2 undergo three-dimensional C-type antiferromagnetic (AFM) ordering of the Mn 2+ moments at T N = 200 ± 10 and 210 ± 12 K, respectively, significantly lower than that of the parent SrMnSb 2 with T N = 297 ± 3 K. Magnetization versus applied magnetic field (perpendicular to MnSb planes) below T N exhibits slightly modified de Haas van Alphen oscillations for the Zn-doped crystal as compared to that of the parent compound. By contrast, the Cu-doped system does not show de Haas van Alphen magnetic oscillations, suggesting that either Cu substitution for Mn changes the electronic structure of the parent compound substantially, or that the Cu sites are strong scatterers of carriers that significantly shorten their mean free path thus diminishing the oscillations. Density functional theory (DFT) calculations including spin-orbit coupling predict the C-type AFM state for the parent, Cu-, and Zn-doped systems and identify the a -axis (i.e., perpendicular to the Mn layer) as the easy magnetization direction in the parent and 12.5% of Cu or Zn substitutions. In contrast, 25% of Cu content changes the easy magnetization to the b-axis (i.e., within the Mn layer). Here, we find that the incorporation of Cu and Zn in SrMnSb 2 tunes electronic bands near the Fermi level resulting in different band topology and semimetallicity. The parent and Zn-doped systems have coexistence of electron and hole pockets with opened Dirac cone around the Y-point whereas the Cu-doped system has dominant hole pockets around the Fermi level with a distorted Dirac cone. The tunable electronic structure may point out possibilities of rationalizing the experimentally observed de Haas van Alphen magnetic oscillations.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
DOE OSTI2021

Determination of the 60 Zn level density from neutron evaporation spectra

Nuclear reactions of interest for astrophysics and applications often rely on statistical model calculations for nuclear reaction rates, particularly for nuclei far from β stability. However, statistical model parameters are often poorly constrained, where experimental constraints are particularly sparse for exotic nuclides. For example, our understanding of the breakout from the NiCu cycle in the astrophysical rp-process is currently limited by uncertainties in the statistical properties of the proton-rich nucleus 60 Zn. We have determined the nuclear level density of 60 Zn using neutron evaporation spectra from 58 Ni( 3 He,n) measured at the Edwards Accelerator Laboratory. We compare our results to a number of theoretical predictions, including phenomenological, microscopic, and shell-model-based approaches. Notably, we find the 60 Zn level density is somewhat lower than expected for excitation energies populated in the 59 Cu(p,γ) 60 Zn reaction under rp-process conditions. This includes a level density plateau from roughly 5 to 6 MeV excitation energy, which is counter to the usual expectation of exponential growth and all theoretical predictions that we explore. Here, a determination of the spin distribution at the relevant excitation energies in 60 Zn is needed to confirm that the Hauser-Feshbach formalism is appropriate for the 59 Cu(p,γ) 60 Zn reaction rate at x-ray burst temperatures

59 ≤ A ≤ 89↗
DOE OSTI2023

Energy coupling and stoichiometry of Zn 2+ /H + antiport by the prokaryotic cation diffusion facilitator YiiP

YiiP from Shewanella oneidensis is a prokaryotic Zn 2+ /H + antiporter that serves as a model for the Cation Diffusion Facilitator (CDF) superfamily, members of which are generally responsible for homeostasis of transition metal ions. Previous studies of YiiP as well as related CDF transporters have established a homodimeric architecture and the presence of three distinct Zn 2+ binding sites named A, B, and C. In this study, we use cryo-EM, microscale thermophoresis and molecular dynamics simulations to address the structural and functional roles of individual sites as well as the interplay between Zn 2+ binding and protonation. Structural studies indicate that site C in the cytoplasmic domain is primarily responsible for stabilizing the dimer and that site B at the cytoplasmic membrane surface controls the structural transition from an inward facing conformation to an occluded conformation. Binding data show that intramembrane site A, which is directly responsible for transport, has a dramatic pH dependence consistent with coupling to the proton motive force. A comprehensive thermodynamic model encompassing Zn 2+ binding and protonation states of individual residues indicates a transport stoichiometry of 1 Zn 2+ to 2–3 H + depending on the external pH. This stoichiometry would be favorable in a physiological context, allowing the cell to use the proton gradient as well as the membrane potential to drive the export of Zn 2+ .

59 BASIC BIOLOGICAL SCIENCES↗
NASA NTRS1991

A comparative study of performance parameters of n(+)-p InP solar cells made by closed-ampoule sulfur diffusion into Cd- and Zn-doped p-type InP substrates

Preliminary results indicate that Cd-doped substrates are better candidates for achieving high efficiency solar cells fabricated by closed-ampoule sulfur (S) diffusion than Zn-doped substrates. The differences in performance parameters (i.e., 14.3 percent efficiency for Cd-doped vs. 11.83 percent in the case of Zn-doped substrates of comparable doping and etch pit densities) were explained in terms of a large increase in dislocation density as a result of S diffusion in the case of Zn-doped as compared to Cd-doped substrates. The In(x)S(y) and probably Zn(S) precipitates in the case of Zn-doped substrates, produce a dead layer which extends deep below the surface and strongly affects the performance parameters. It should be noted that the cells had an unoptimized single layer antireflective coating of SiO, a grid shadowing of 6.25 percent, and somewhat poor contacts, all contributing to a reduction in efficiency. It is believed that by reducing the external losses and further improvement in cell design, efficiencies approaching 17 percent at 1 AMO, 25 degrees should be possible for cells fabricated on these relatively high defect density Cd-doped substrates. Even higher efficiencies, 18 to 19 percent should be possible by using long-lifetime substrates and further improving front surface passivation. If solar cells fabricated on Cd-doped substrates turn out to have comparable radiation tolerance as those reported in the case of cells fabricated on Zn-doped substrates, then for certain space missions 18 to 19 percent efficient cells made by this method of fabrication would be viable.

Faur, Mircea↗
NASA NTRS2005

Composition-Temperature-Partial Pressures Data for Cd(sub 0.8)Zn(sub 0.2)Te by Optical Absorption Measurements

Known weights of Cd, Zn and Te were reacted in silica optical cells of known volume and the partial pressure of Te2 and Zn between 485 and 1160 C were determined by measuring the optical density of the vapor in the ultra-violet to visible range. The composition of the condensed phase or phases was calculated from the original weights and the amount of material in the vapor phase. The corresponding composition - temperature - partial pressures, x(sub Te)-T-P(sub Te2), data, including five Te-rich solidus points, were established. The solubility range for the Te-rich Cd(sub 0.8)Zn(sub 0.2)Te(s) is similar to that of CdTe(s) with x(sub Te) = 0.50005 at 809 C and an estimated maximum solubility of x(sub Te) = 0.50012 at about 1000 C. The partial pressure of Cd and Te(sub 2) measured over the Cd(sub 0.8)Zn(sub 0.2)Te melt at 1140 C were about 1.55 and 0.02 atm, respectively, and the corresponding P(Sub Zn) was estimated to be 0.05 atm. It was recommended that a Cd reservoir maintaining at 800 to 820 C should be used during directional solidification of Cd(sub o.8)Zn(sub 0.2)Te to prevent the preferential loss of Cd to the vapor phase.

Su, Ching-Hua↗
DOE OSTI2022

Direct Ink Writing of 3D Zn Structures as High‐Capacity Anodes for Rechargeable Alkaline Batteries

The relationship between structure and performance in alkaline Zn batteries is undeniable, where anode utilization, dendrite formation, shape change, and passivation issues are all addressable through anode morphology. While tailoring 3D hosts can improve the electrode performance, these practices are inherently limited by scaffolds that increase the mass or volume. Herein, a direct write strategy for producing template‐free metallic 3D Zn electrode architectures is discussed. Concentrated inks are customized to build designs with low electrical resistivity (5 × 10 −4 Ω cm), submillimeter sizes (200 μm filaments), and high mechanical stability (Young's modulus of 0.1–0.5 GPa at relative densities of 0.28–0.46). A printed Zn lattice anode versus NiOOH cathode with an alkaline polymer gel electrolyte is then demonstrated. This Zn||NiOOH cell operates for over 650 cycles at high rates of 25 mA cm −2 with an average areal capacity of 11.89 mAh cm −2 , a cumulative capacity of 7.8 Ah cm −2 , and a volumetric capacity of 23.78 mAh cm −3 . A thicker Zn anode achieves an ultrahigh areal capacity of 85.45 mAh cm −2 and a volumetric capacity of 81.45 mAh cm −3 without significant microstructural changes after 50 cycles.

25 ENERGY STORAGE↗
DOE OSTI2020

Materials Data on Zn(NiO2)2 by Materials Project

Zn(NiO2)2 crystallizes in the monoclinic Pm space group. The structure is three-dimensional. there are six inequivalent Ni3+ sites. In the first Ni3+ site, Ni3+ is bonded to six O2- atoms to form NiO6 octahedra that share corners with five ZnO6 pentagonal pyramids, edges with six NiO6 octahedra, an edgeedge with one ZnO6 pentagonal pyramid, and a faceface with one ZnO6 pentagonal pyramid. There are a spread of Ni–O bond distances ranging from 1.94–2.09 Å. In the second Ni3+ site, Ni3+ is bonded to six O2- atoms to form NiO6 octahedra that share corners with five ZnO6 pentagonal pyramids, edges with six NiO6 octahedra, an edgeedge with one ZnO6 pentagonal pyramid, and a faceface with one ZnO6 pentagonal pyramid. There are a spread of Ni–O bond distances ranging from 1.93–2.07 Å. In the third Ni3+ site, Ni3+ is bonded to six O2- atoms to form NiO6 octahedra that share corners with five ZnO6 pentagonal pyramids, edges with six NiO6 octahedra, an edgeedge with one ZnO6 pentagonal pyramid, and a faceface with one ZnO6 pentagonal pyramid. There are a spread of Ni–O bond distances ranging from 1.94–2.08 Å. In the fourth Ni3+ site, Ni3+ is bonded to six O2- atoms to form NiO6 octahedra that share corners with five ZnO6 pentagonal pyramids, edges with six NiO6 octahedra, an edgeedge with one ZnO6 pentagonal pyramid, and a faceface with one ZnO6 pentagonal pyramid. There are a spread of Ni–O bond distances ranging from 1.95–2.08 Å. In the fifth Ni3+ site, Ni3+ is bonded to six O2- atoms to form NiO6 octahedra that share corners with four ZnO6 pentagonal pyramids, edges with six NiO6 octahedra, and edges with two ZnO6 pentagonal pyramids. There are a spread of Ni–O bond distances ranging from 1.88–2.02 Å. In the sixth Ni3+ site, Ni3+ is bonded to six O2- atoms to form NiO6 octahedra that share corners with four ZnO6 pentagonal pyramids, edges with six NiO6 octahedra, and edges with two ZnO6 pentagonal pyramids. There are a spread of Ni–O bond distances ranging from 1.88–2.03 Å. There are four inequivalent Zn2+ sites. In the first Zn2+ site, Zn2+ is bonded to six O2- atoms to form distorted ZnO6 pentagonal pyramids that share corners with six NiO6 octahedra, edges with six NiO6 octahedra, and edges with two equivalent ZnO6 pentagonal pyramids. The corner-sharing octahedra tilt angles range from 1–19°. There are a spread of Zn–O bond distances ranging from 2.09–2.16 Å. In the second Zn2+ site, Zn2+ is bonded to six O2- atoms to form distorted ZnO6 pentagonal pyramids that share corners with six NiO6 octahedra, edges with six NiO6 octahedra, and edges with two equivalent ZnO6 pentagonal pyramids. The corner-sharing octahedra tilt angles range from 1–19°. There are a spread of Zn–O bond distances ranging from 2.10–2.15 Å. In the third Zn2+ site, Zn2+ is bonded to six O2- atoms to form distorted ZnO6 pentagonal pyramids that share corners with twelve NiO6 octahedra, edges with two equivalent ZnO6 pentagonal pyramids, and faces with two NiO6 octahedra. The corner-sharing octahedra tilt angles range from 44–53°. There are a spread of Zn–O bond distances ranging from 2.10–2.18 Å. In the fourth Zn2+ site, Zn2+ is bonded to six O2- atoms to form distorted ZnO6 pentagonal pyramids that share corners with twelve NiO6 octahedra, edges with two equivalent ZnO6 pentagonal pyramids, and faces with two NiO6 octahedra. The corner-sharing octahedra tilt angles range from 44–53°. There are a spread of Zn–O bond distances ranging from 2.11–2.18 Å. There are twelve inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted see-saw-like geometry to three Ni3+ and one Zn2+ atom. In the second O2- site, O2- is bonded in a distorted see-saw-like geometry to three Ni3+ and one Zn2+ atom. In the third O2- site, O2- is bonded in a distorted see-saw-like geometry to three Ni3+ and one Zn2+ atom. In the fourth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to three Ni3+ and one Zn2+ atom. In the fifth O2- site, O2- is bonded in a rectangular see-saw-like geometry to three Ni3+ and one Zn2+ atom. In the sixth O2- site, O2- is bonded in a rectangular see-saw-like geometry to three Ni3+ and one Zn2+ atom. In the seventh O2- site, O2- is bonded in a rectangular see-saw-like geometry to three Ni3+ and one Zn2+ atom. In the eighth O2- site, O2- is bonded in a rectangular see-saw-like geometry to three Ni3+ and one Zn2+ atom. In the ninth O2- site, O2- is bonded to three Ni3+ and two Zn2+ atoms to form a mixture of edge and corner-sharing OZn2Ni3 trigonal bipyramids. In the tenth O2- site, O2- is bonded to three Ni3+ and two Zn2+ atoms to form a mixture of edge and corner-sharing OZn2Ni3 trigonal bipyramids. In the eleventh O2- site, O2- is bonded to three Ni3+ and two Zn2+ atoms to form a mixture of edge and corner-sharing OZn2Ni3 trigonal bipyramids. In the twelfth O2- site, O2- is bonded to three Ni3+ and two Zn2+ atoms to form a mixture of edge and corner-sharing OZn2Ni3 trigonal bipyramids.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Zn(CuO2)2 by Materials Project

Zn(CuO2)2 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are eight inequivalent Cu3+ sites. In the first Cu3+ site, Cu3+ is bonded to six O2- atoms to form a mixture of edge and corner-sharing CuO6 octahedra. The corner-sharing octahedra tilt angles range from 49–62°. There are a spread of Cu–O bond distances ranging from 1.94–2.06 Å. In the second Cu3+ site, Cu3+ is bonded to six O2- atoms to form a mixture of edge and corner-sharing CuO6 octahedra. The corner-sharing octahedra tilt angles range from 48–61°. There are a spread of Cu–O bond distances ranging from 1.93–2.09 Å. In the third Cu3+ site, Cu3+ is bonded to six O2- atoms to form a mixture of edge and corner-sharing CuO6 octahedra. The corner-sharing octahedra tilt angles range from 48–62°. There are a spread of Cu–O bond distances ranging from 1.94–2.07 Å. In the fourth Cu3+ site, Cu3+ is bonded to six O2- atoms to form a mixture of edge and corner-sharing CuO6 octahedra. The corner-sharing octahedra tilt angles range from 49–61°. There are a spread of Cu–O bond distances ranging from 1.95–2.07 Å. In the fifth Cu3+ site, Cu3+ is bonded to six O2- atoms to form a mixture of edge and corner-sharing CuO6 octahedra. The corner-sharing octahedra tilt angles range from 49–62°. There are a spread of Cu–O bond distances ranging from 1.90–2.13 Å. In the sixth Cu3+ site, Cu3+ is bonded to six O2- atoms to form a mixture of edge and corner-sharing CuO6 octahedra. The corner-sharing octahedra tilt angles range from 49–61°. There are a spread of Cu–O bond distances ranging from 1.90–2.11 Å. In the seventh Cu3+ site, Cu3+ is bonded to six O2- atoms to form a mixture of edge and corner-sharing CuO6 octahedra. The corner-sharing octahedra tilt angles range from 48–62°. There are a spread of Cu–O bond distances ranging from 1.91–2.09 Å. In the eighth Cu3+ site, Cu3+ is bonded to six O2- atoms to form a mixture of edge and corner-sharing CuO6 octahedra. The corner-sharing octahedra tilt angles range from 48–61°. There are a spread of Cu–O bond distances ranging from 1.90–2.12 Å. There are four inequivalent Zn2+ sites. In the first Zn2+ site, Zn2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Zn–O bond distances ranging from 2.20–2.47 Å. In the second Zn2+ site, Zn2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Zn–O bond distances ranging from 2.20–2.49 Å. In the third Zn2+ site, Zn2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Zn–O bond distances ranging from 2.22–2.54 Å. In the fourth Zn2+ site, Zn2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Zn–O bond distances ranging from 2.21–2.48 Å. There are sixteen inequivalent O2- sites. In the first O2- site, O2- is bonded to three Cu3+ and two equivalent Zn2+ atoms to form a mixture of distorted edge and corner-sharing OZn2Cu3 trigonal bipyramids. In the second O2- site, O2- is bonded to three Cu3+ and two equivalent Zn2+ atoms to form a mixture of distorted edge and corner-sharing OZn2Cu3 trigonal bipyramids. In the third O2- site, O2- is bonded to three Cu3+ and two equivalent Zn2+ atoms to form a mixture of distorted edge and corner-sharing OZn2Cu3 trigonal bipyramids. In the fourth O2- site, O2- is bonded to three Cu3+ and two equivalent Zn2+ atoms to form a mixture of distorted edge and corner-sharing OZn2Cu3 trigonal bipyramids. In the fifth O2- site, O2- is bonded in a 5-coordinate geometry to three Cu3+ and two Zn2+ atoms. In the sixth O2- site, O2- is bonded in a 5-coordinate geometry to three Cu3+ and two Zn2+ atoms. In the seventh O2- site, O2- is bonded in a 5-coordinate geometry to three Cu3+ and two Zn2+ atoms. In the eighth O2- site, O2- is bonded in a 5-coordinate geometry to three Cu3+ and two Zn2+ atoms. In the ninth O2- site, O2- is bonded to three Cu3+ and two equivalent Zn2+ atoms to form a mixture of distorted edge and corner-sharing OZn2Cu3 trigonal bipyramids. In the tenth O2- site, O2- is bonded to three Cu3+ and two equivalent Zn2+ atoms to form a mixture of distorted edge and corner-sharing OZn2Cu3 trigonal bipyramids. In the eleventh O2- site, O2- is bonded to three Cu3+ and two equivalent Zn2+ atoms to form a mixture of distorted edge and corner-sharing OZn2Cu3 trigonal bipyramids. In the twelfth O2- site, O2- is bonded to three Cu3+ and two equivalent Zn2+ atoms to form a mixture of distorted edge and corner-sharing OZn2Cu3 trigonal bipyramids. In the thirteenth O2- site, O2- is bonded in a 5-coordinate geometry to three Cu3+ and two equivalent Zn2+ atoms. In the fourteenth O2- site, O2- is bonded in a 5-coordinate geometry to three Cu3+ and two equivalent Zn2+ atoms. In the fifteenth O2- site, O2- is bonded in a 5-coordinate geometry to three Cu3+ and two equivalent Zn2+ atoms. In the sixteenth O2- site, O2- is bonded in a 5-coordinate geometry to three Cu3+ and two equivalent Zn2+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Zn(InAu4)3 by Materials Project

Zn(Au4In)3 is beta Cu3Ti-derived structured and crystallizes in the orthorhombic Pmm2 space group. The structure is three-dimensional. there are seven inequivalent Au+0.75- sites. In the first Au+0.75- site, Au+0.75- is bonded in a distorted see-saw-like geometry to eight Au+0.75-, two equivalent Zn2+, and two equivalent In+2.33+ atoms. There are six shorter (2.95 Å) and two longer (3.10 Å) Au–Au bond lengths. Both Au–Zn bond lengths are 2.94 Å. Both Au–In bond lengths are 2.92 Å. In the second Au+0.75- site, Au+0.75- is bonded in a distorted see-saw-like geometry to eight Au+0.75- and four In+2.33+ atoms. There are four shorter (2.96 Å) and four longer (3.05 Å) Au–Au bond lengths. There are two shorter (2.95 Å) and two longer (2.97 Å) Au–In bond lengths. In the third Au+0.75- site, Au+0.75- is bonded in a distorted see-saw-like geometry to eight Au+0.75-, one Zn2+, and three In+2.33+ atoms. There are a spread of Au–Au bond distances ranging from 2.92–3.08 Å. The Au–Zn bond length is 2.86 Å. There are two shorter (2.97 Å) and one longer (3.00 Å) Au–In bond lengths. In the fourth Au+0.75- site, Au+0.75- is bonded to eight Au+0.75-, two equivalent Zn2+, and two equivalent In+2.33+ atoms to form distorted AuZn2In2Au8 cuboctahedra that share corners with four equivalent ZnAu12 cuboctahedra, corners with ten AuIn4Au8 cuboctahedra, edges with four AuZn2In2Au8 cuboctahedra, edges with six InAu12 cuboctahedra, faces with two equivalent ZnAu12 cuboctahedra, faces with two equivalent InAu12 cuboctahedra, and faces with six AuZn2In2Au8 cuboctahedra. There are a spread of Au–Au bond distances ranging from 2.88–2.98 Å. There are one shorter (3.02 Å) and one longer (3.05 Å) Au–Zn bond lengths. Both Au–In bond lengths are 2.95 Å. In the fifth Au+0.75- site, Au+0.75- is bonded to eight Au+0.75- and four In+2.33+ atoms to form distorted AuIn4Au8 cuboctahedra that share corners with four equivalent InAu12 cuboctahedra, corners with ten AuZn2In2Au8 cuboctahedra, edges with two equivalent ZnAu12 cuboctahedra, edges with four AuIn4Au8 cuboctahedra, edges with four equivalent InAu12 cuboctahedra, faces with four InAu12 cuboctahedra, and faces with ten AuZn2In2Au8 cuboctahedra. There are two shorter (2.96 Å) and one longer (2.98 Å) Au–Au bond lengths. There are a spread of Au–In bond distances ranging from 2.94–3.07 Å. In the sixth Au+0.75- site, Au+0.75- is bonded in a 12-coordinate geometry to eight Au+0.75-, two equivalent Zn2+, and two equivalent In+2.33+ atoms. There are one shorter (2.82 Å) and one longer (2.98 Å) Au–Au bond lengths. Both Au–Zn bond lengths are 2.90 Å. There are one shorter (3.05 Å) and one longer (3.08 Å) Au–In bond lengths. In the seventh Au+0.75- site, Au+0.75- is bonded to eight Au+0.75- and four In+2.33+ atoms to form distorted AuIn4Au8 cuboctahedra that share corners with four equivalent AuIn4Au8 cuboctahedra, corners with four equivalent InAu12 cuboctahedra, edges with two equivalent ZnAu12 cuboctahedra, edges with four InAu12 cuboctahedra, edges with six AuZn2In2Au8 cuboctahedra, faces with four InAu12 cuboctahedra, and faces with eleven AuZn2In2Au8 cuboctahedra. The Au–Au bond length is 2.95 Å. There are a spread of Au–In bond distances ranging from 2.94–3.06 Å. Zn2+ is bonded to twelve Au+0.75- atoms to form ZnAu12 cuboctahedra that share corners with two equivalent InAu12 cuboctahedra, corners with eight equivalent AuZn2In2Au8 cuboctahedra, edges with two equivalent ZnAu12 cuboctahedra, edges with four equivalent InAu12 cuboctahedra, edges with eight AuIn4Au8 cuboctahedra, faces with two equivalent ZnAu12 cuboctahedra, faces with four equivalent AuZn2In2Au8 cuboctahedra, and faces with four equivalent InAu12 cuboctahedra. There are two inequivalent In+2.33+ sites. In the first In+2.33+ site, In+2.33+ is bonded to twelve Au+0.75- atoms to form InAu12 cuboctahedra that share corners with two equivalent ZnAu12 cuboctahedra, corners with eight equivalent AuIn4Au8 cuboctahedra, edges with six InAu12 cuboctahedra, edges with eight AuZn2In2Au8 cuboctahedra, faces with six InAu12 cuboctahedra, and faces with eight AuIn4Au8 cuboctahedra. In the second In+2.33+ site, In+2.33+ is bonded to twelve Au+0.75- atoms to form InAu12 cuboctahedra that share corners with two equivalent InAu12 cuboctahedra, corners with four equivalent AuIn4Au8 cuboctahedra, edges with two equivalent ZnAu12 cuboctahedra, edges with four InAu12 cuboctahedra, edges with ten AuZn2In2Au8 cuboctahedra, faces with two equivalent ZnAu12 cuboctahedra, faces with four InAu12 cuboctahedra, and faces with six AuZn2In2Au8 cuboctahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2022

Thermodynamic modeling of the Pd–Zn system with uncertainty quantification and its implication to tailor catalysts

Pd–Zn intermetallic catalysts show encouraging combinations of activity and selectivity on well-defined active site ensembles. Thermodynamic description of the Pd–Zn system, delineating phase boundaries and enumerating site occupancies within intermediate alloy phases, is essential to determining the ensembles of Pd–Zn atoms as a function of composition and temperature. Combining the present extensive first-principles calculations based on density functional theory (DFT) and available experimental data, the Pd–Zn system was remodeled using the CALculation of PHAse Diagrams (CALPHAD) approach. High throughput modeling tools with uncertainty quantification, i.e., ESPEI and PyCalphad, were incorporated in the phase analysis. Here, the site occupancies across the γ phase composition region were given special attention. A four-sublattice model was used for the γ phase owing to its four Wyckoff positions, i.e., the outer tetrahedral (OT) site 8c, the inner tetrahedral (IT) site 8c, the octahedral (OH) site 12e, and the cuboctahedral (CO) site 24g. The site fractions of Pd and Zn calculated from the present thermodynamic model show the occupancy preference of Pd in the OT and OH sublattices in agreement with experimental observations. The force constants obtained from DFT-based phonon calculations further supports the tendency of Pd occupying the OH sublattice compared with the IT and CO sublattice. The catalytic ensembles changing from Pd monomers (Pd 1 ) to trimers (Pd 3 ) on the surface of γ phase are attributed to the increase of Pd occupancy in the OH sublattice.

36 MATERIALS SCIENCE↗
DOE OSTI2024

Suppressing metal corrosion through identification of optimal crystallographic plane for Zn batteries

Direct use of metals as battery anodes could significantly boost the energy density, but suffers from limited cycling. To make the batteries more sustainable, one strategy is mitigating the propensity for metals to form random morphology during plating through orientation regulation, e.g., hexagonal Zn platelets locked horizontally by epitaxial electrodeposition or vertically aligned through Zn/electrolyte interface modulation. Current strategies center around obtaining (002) faceted deposition due to its minimum surface energy. Here, benefiting from the capability of preparing a library of faceted monocrystalline Zn anodes and controlling the orientation of Zn platelet deposits, we challenge this conventional belief. We show that while monocrystalline (002) faceted Zn electrode with horizontal epitaxy indeed promises the highest critical current density, the (100) faceted electrode with vertically aligned deposits is the most important one in suppressing Zn metal corrosion and promising the best reversibility. Such uniqueness results from the lowest electrochemical surface area of (100) faceted electrode, which intrinsically builds upon the surface atom diffusion barrier and the orientation of the pallets. These new findings based on monocrystalline anodes advance the fundamental understanding of electrodeposition process for sustainable metal batteries and provide a paradigm to explore the processing–structure–property relationships of metal electrodes.

25 ENERGY STORAGE↗
DOE OSTI2020

Materials Data on Zn by Materials Project

Zn is Magnesium structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. Zn is bonded to twelve equivalent Zn atoms to form a mixture of edge, face, and corner-sharing ZnZn12 cuboctahedra. There are six shorter (2.63 Å) and six longer (3.01 Å) Zn–Zn bond lengths.

36 MATERIALS SCIENCE↗
DOE OSTI2024

Effect of Zn Addition on Phase Evolution in AlCrFeCoNiZn High–Entropy Alloy

The addition of Zn to AlCrFeCoNi high-entropy alloy (HEA) poses intriguing questions as to how it would affect phase evolution. Herein, the phase evolution in AlCrFeCoNiZn is studied using a combination of experimental techniques (X-ray diffraction, scanning electron microscopy, energy-dispersive spectroscopy, and differential scanning calorimetry) and computational (density-functional theory [DFT], calculation of phase diagrams, and machine-learning) methods. Mechanically alloyed and spark-plasma-sintered AlCrFeCoNiZn assumes a metastable single-phase, body-centered-cubic (BCC) structure that undergoes diffusion-controlled phase separation upon subsequent heat treatment to form separate (Al, Cr)-rich, (Fe, Co)-rich, and (Zn, Ni)-rich phases. The formation of (Al, Cr)-rich phase, not reported previously in AlCrFeCoNi-based HEAs, is attributed to strong clustering tendency of Cr–Zn and Cr–Ni pairs, combined with the strong ordering of Zn–Ni pair, driving out Cr that in turn combines with Al to form a (Al, Cr)-rich phase. In the DFT results, the formation of thermodynamically stable L1 2 phase is shown wherein Cr–Fe–Zn [Al–Ni-Co] preferably occupy1a (000) [3c (0 ½ ½)] positions. Furthermore, the sluggish diffusional transformation to L1 2 phase from BCC precursors is attributed to the small stacking-fault energy of AlCrFeCoNiZn. The equilibrated HEA exhibits a high microhardness of 8.24 GPa with an elastic modulus of 184 GPa.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Reversible (De)Intercalation of Hydrated Zn 2+ in Mg 2+ -Stabilized V 2 O 5 Nanobelts with High Areal Capacity

The rechargeable aqueous zinc ion battery (ZIB) is regarded as one of the most promising candidates for large-scale energy storage applications due to its low-cost and eco-friendly properties. However, the development of a suitable cathode operating with high areal capacity and uncovering the relevant reaction mechanisms remain challenging. Herein, the application of Mg 0.26 V 2 O 5 ∙0.73H 2 O (MVO) nanobelts as a ZIB cathode is demonstrated. In situ FT-IR reveals the shift of OH stretching from 3350 cm -1 to 3200 cm -1 , corresponding to the hydration shell of Zn 2+ , while in situ Raman suggests the interlayer charges creening effect, which would boost the intercalation of hydrated Zn 2+ . Density function theory reveals that the hydrated Zn 2+ can lower the Coulombic repulsion at the electrode-electrolyte interface and circumvents the desolvation penalty of hydrated Zn 2+ during the (de)intercalation process. Additionally, excellent structure stability and large interlayer spacing guarantee the highly reversible (de)intercalation of hydrated Zn 2+ . Therefore, the MVO nanobelts exhibit a high areal capacity of 2.12 mAh cm -2 at 0.05 A g -1 , outstanding cycling stability of 2500 cycles at 10 A g -1 with a mass loading of 5 mg cm -2 . Finally, it is believed that the use of hydrated intercalation charge carriers will boost further studies in other multivalent rechargeable batteries.

25 ENERGY STORAGE↗