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DOE OSTI2020

Materials Data on NpAgSeO5 by Materials Project

NpAgSeO5 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are two inequivalent Np5+ sites. In the first Np5+ site, Np5+ is bonded to seven O2- atoms to form distorted corner-sharing NpO7 pentagonal bipyramids. There are a spread of Np–O bond distances ranging from 1.88–2.54 Å. In the second Np5+ site, Np5+ is bonded to seven O2- atoms to form distorted corner-sharing NpO7 pentagonal bipyramids. There are a spread of Np–O bond distances ranging from 1.89–2.48 Å. There are two inequivalent Ag1+ sites. In the first Ag1+ site, Ag1+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Ag–O bond distances ranging from 2.38–2.76 Å. In the second Ag1+ site, Ag1+ is bonded in a 6-coordinate geometry to eight O2- atoms. There are a spread of Ag–O bond distances ranging from 2.37–3.11 Å. There are two inequivalent Se4+ sites. In the first Se4+ site, Se4+ is bonded in a trigonal non-coplanar geometry to three O2- atoms. There are a spread of Se–O bond distances ranging from 1.71–1.76 Å. In the second Se4+ site, Se4+ is bonded in a distorted trigonal non-coplanar geometry to three O2- atoms. There are a spread of Se–O bond distances ranging from 1.73–1.76 Å. There are ten inequivalent O2- sites. In the first O2- site, O2- is bonded in a 1-coordinate geometry to two Np5+ atoms. In the second O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Np5+, two Ag1+, and one Se4+ atom. In the third O2- site, O2- is bonded in a 3-coordinate geometry to one Np5+, two Ag1+, and one Se4+ atom. In the fourth O2- site, O2- is bonded in a distorted single-bond geometry to two Np5+ and one Ag1+ atom. In the fifth O2- site, O2- is bonded in a 4-coordinate geometry to one Np5+, two equivalent Ag1+, and one Se4+ atom. In the sixth O2- site, O2- is bonded in a bent 120 degrees geometry to one Np5+ and one Se4+ atom. In the seventh O2- site, O2- is bonded in a 1-coordinate geometry to two Np5+ and one Ag1+ atom. In the eighth O2- site, O2- is bonded in a 1-coordinate geometry to one Np5+, two Ag1+, and one Se4+ atom. In the ninth O2- site, O2- is bonded in a 1-coordinate geometry to one Np5+, three Ag1+, and one Se4+ atom. In the tenth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two Np5+ atoms.

36 MATERIALS SCIENCE↗

DOE OSTI2020

Large-scale production of 88 Y and 88 Zr/ 88 Y generators: A proof of concept study for a 70 MeV H – cyclotron

Here, the large-scale production of 88 Y with proton-induced reactions has been investigated from the perspective of new generation 70 MeV H – cyclotrons. Tandem target configurations are presented for both the direct production of 88 Y as well as for producing 88 Zr/ 88 Y generators. Based on the relevant excitation functions, physical yields have been derived for 88 Y production with Y 2 O 3 /SrCO 3 tandem targets and 88 Zr production with Zr/Y 2 O 3 tandem targets. Yields are presented for optimized targets (i.e. optimum yield) as well as for balanced thermal loads on the individual targets. Liquid 88 Zr/ 88 Y generators have been produced using both natural Zr and Nb target materials, the former for dedicated productions and the latter as a byproduct by processing spent irradiated Nb capsules which normally would constitute radioactive waste. These stock solutions, which contain both the target material and 88 Zr precursor, are retained virtually unchanged after processing except for the removal of 88 Y on AG MP-50 macroporous cation-exchange resin. Methods are presented for the preparation of Nb stock solutions in hydrofluoric acid and Zr stock solutions in sulfuric acid. It is shown that multi-Ci productions of 88 Y are feasible at a 70 MeV cyclotron facility, suitable for the needs of fracking applications. In addition, 88 Zr/ 88 Y generators can provide 88 Y with very high specific activity, suitable for labelling of biomolecules.

07 ISOTOPE AND RADIATION SOURCES↗

NASA NTRSDate not supplied

Broad Compatibility Study of Polymeric Materials with Ionic Silver Biocide, Part I

NASA is considering ionic silver as a residual biocide for use in potable water systems being planned for future exploration spacecraft. Compatibility of the biocide with the system’s wetted-materials of construction remains a challenge. Due to the relatively inert nature of plastics, their use in varied water system applications may offer unique opportunities to address many biocide compatibility issues. A 2020 ICES paper described a “Stage 1” assessment of several polymeric materials, in which coupons having a 2 cm 1 surface to volume ratio were exposed to solutions of 400 parts per billion (ppb) aqueous silver fluoride (AgF) for one week. In this current paper, additional Stage 1 test results are presented for select epoxies and lubricants applied on silver-inert substrates. The coupon exposure studies were also expanded to a duration of 5 weeks for the “well-behaved” Stage 1 plastics previously reported: those exhibiting silver losses above 10% and less than 50%. For this type of Stage 2 testing, silver biocide solution samples are taken from three separate (and not previously-sampled) coupon containers after 3 days, and 2, 3, 4, and 5 weeks of exposure. "Very well-behaved" Stage 1 plastics will be tested in the same manner over one year, with longer sample intervals; early-period results are included here. In addition, for select materials, the coupons were “aged” by refilling test containers with fresh AgF and observing the respective silver uptake over similar Stage 2 test durations. For all test series, Inductively Coupled Plasma Mass Spectrometry (ICP-MS) and ion-selective electrode (ISE) analyses were used to determine total and ionic silver (Ag+) concentrations, respectively. Additional sample analyses for Stage 2 tests includes total organic carbon (TOC), pH, conductivity, and oxidation-reduction potential (ORP). Ultimately, these early compatibility studies will be used to guide future material selections for developing silver biocide-compatible spacecraft water systems.

Silver Biocide↗

DOE OSTI2020

Lead-Free Cs 4 CuSb 2 Cl 12 Layered Double Perovskite Nanocrystals

Concerns about the toxicity of lead-based perovskites have aroused great interest for the development of alternative lead-free perovskite-type materials. Recently, theoretical calculations predict that Pb 2+ cations can be substituted by a combination of Cu 2+ and Sb 3+ cations to form a vacancy-ordered layered double perovskite structure with superior optoelectronic properties. However, accessibilities to this class of perovskite-type materials remain inadequate, hindering their practical implementations in various applications. Here, we report the first colloidal synthesis of Cs 4 CuSb 2 Cl 12 perovskite-type nanocrystals (NCs). The resulting NCs exhibit a layered double perovskite structure with ordered vacancies and a direct bandgap of 1.79 eV. A composition-structure-property relationship has been established by investigating a series of Cs 4 Cu x Ag 2-2x Sb 2 Cl 12 perovskite-type NCs (0 ≤ x ≤ 1). The composition-induced crystal structure transformation, thus the electronic bandgap evolution has been explored by experimental observations and further confirmed by theoretical calculations. Taking advantages of both the unique electronic structure and solution processability, we demonstrate that the Cs 4 CuSb 2 Cl 12 NCs can be solution-processed as high-speed photodetectors with ultrafast photo-response and narrow bandwidth. We anticipate that our study will prompt future research to design and fabricate novel and high-performance lead-free perovskite-type NCs for a range of applications.

25 ENERGY STORAGE↗

DOE OSTI2022

A reaction mechanism for plasma electrolysis of AgNO 3 forming silver nanoclusters and nanoparticles

In plasma-driven solution electrolysis (PDSE), gas-phase plasma-produced species interact with an electrolytic solution to produce, for example, nanoparticles. An atmospheric pressure plasma jet (APPJ) directed onto a liquid solution containing a metallic salt will promote reduction of metallic ions in solution, generating metallic clusters that nucleate to form nanoparticles. In this article, results from a computational investigation are discussed of a PDSE process in which a radio-frequency APPJ sustained in helium impinges on a silver nitrate solution, resulting in growth of silver nanoparticles. A reaction mechanism was developed and implemented in a global plasma chemistry model to predict nanoparticle growth. To develop the reaction mechanism, density functional theory was used to generate probable silver growth pathways up to Ag 9 . Neutral clusters larger than Ag 9 were classified as nanoparticles. Kinetic reaction rate coefficients for thermodynamically favorable growth pathways were estimated based on an existing, empirically determined base reaction mechanism for smaller Ag particle interactions. These rates were used in conjunction with diffusion-controlled reaction rate coefficients that were calculated for other Ag species. The role of anions in reduction of Agn ions in forming nanoparticles is also discussed. Oxygen containing impurities or admixtures to the helium, air entrainment into the APPJ, and dissociation of saturated water vapor above the solution can produce additional reactive oxygen species in solution, resulting in the production of anions and O 2 – in particular. For a given molarity, delivering a sufficient fluence of reducing species will produce similar nanoparticle densities and sizes for all applied power levels. In conclusion, comparisons are made to alternate models for nanoparticle formation, including charged nanoparticles and use of direct current plasmas.

36 MATERIALS SCIENCE↗

DOE OSTI2020

Materials Data on KNb4Ag(PS10)2 by Materials Project

KNb4Ag(PS10)2 crystallizes in the triclinic P1 space group. The structure is three-dimensional. K1+ is bonded in a 8-coordinate geometry to eight S+1.60- atoms. There are a spread of K–S bond distances ranging from 3.33–3.68 Å. There are four inequivalent Nb5+ sites. In the first Nb5+ site, Nb5+ is bonded to eight S+1.60- atoms to form distorted NbS8 hexagonal bipyramids that share an edgeedge with one PS4 tetrahedra and faces with two NbS8 hexagonal bipyramids. There are a spread of Nb–S bond distances ranging from 2.52–2.63 Å. In the second Nb5+ site, Nb5+ is bonded to eight S+1.60- atoms to form distorted NbS8 hexagonal bipyramids that share an edgeedge with one PS4 tetrahedra and faces with two NbS8 hexagonal bipyramids. There are a spread of Nb–S bond distances ranging from 2.52–2.65 Å. In the third Nb5+ site, Nb5+ is bonded to eight S+1.60- atoms to form distorted NbS8 hexagonal bipyramids that share an edgeedge with one PS4 tetrahedra and faces with two NbS8 hexagonal bipyramids. There are a spread of Nb–S bond distances ranging from 2.52–2.62 Å. In the fourth Nb5+ site, Nb5+ is bonded to eight S+1.60- atoms to form distorted NbS8 hexagonal bipyramids that share an edgeedge with one PS4 tetrahedra and faces with two NbS8 hexagonal bipyramids. There are a spread of Nb–S bond distances ranging from 2.52–2.64 Å. Ag1+ is bonded in a 2-coordinate geometry to eight S+1.60- atoms. There are a spread of Ag–S bond distances ranging from 2.47–3.56 Å. There are two inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four S+1.60- atoms to form PS4 tetrahedra that share edges with two NbS8 hexagonal bipyramids. There are a spread of P–S bond distances ranging from 2.01–2.10 Å. In the second P5+ site, P5+ is bonded to four S+1.60- atoms to form PS4 tetrahedra that share edges with two NbS8 hexagonal bipyramids. There are a spread of P–S bond distances ranging from 2.02–2.09 Å. There are twenty inequivalent S+1.60- sites. In the first S+1.60- site, S+1.60- is bonded in a 3-coordinate geometry to two Nb5+ and one S+1.60- atom. The S–S bond length is 2.06 Å. In the second S+1.60- site, S+1.60- is bonded in a 4-coordinate geometry to one K1+, two Nb5+, and one S+1.60- atom. The S–S bond length is 2.05 Å. In the third S+1.60- site, S+1.60- is bonded in a 3-coordinate geometry to two Nb5+ and one P5+ atom. In the fourth S+1.60- site, S+1.60- is bonded in a 3-coordinate geometry to two Nb5+ and one P5+ atom. In the fifth S+1.60- site, S+1.60- is bonded in a 2-coordinate geometry to two Nb5+, one Ag1+, and one S+1.60- atom. The S–S bond length is 2.05 Å. In the sixth S+1.60- site, S+1.60- is bonded in a 2-coordinate geometry to two Nb5+, one Ag1+, and one S+1.60- atom. The S–S bond length is 2.05 Å. In the seventh S+1.60- site, S+1.60- is bonded in a 3-coordinate geometry to two Nb5+ and one S+1.60- atom. In the eighth S+1.60- site, S+1.60- is bonded in a 2-coordinate geometry to one K1+, two Nb5+, and one S+1.60- atom. In the ninth S+1.60- site, S+1.60- is bonded in a 4-coordinate geometry to two Nb5+, one Ag1+, and one S+1.60- atom. In the tenth S+1.60- site, S+1.60- is bonded in a 4-coordinate geometry to two Nb5+, one Ag1+, and one S+1.60- atom. In the eleventh S+1.60- site, S+1.60- is bonded in an L-shaped geometry to one Ag1+ and one P5+ atom. In the twelfth S+1.60- site, S+1.60- is bonded in a distorted T-shaped geometry to one K1+, one Ag1+, and one P5+ atom. In the thirteenth S+1.60- site, S+1.60- is bonded in a distorted L-shaped geometry to one Nb5+, one Ag1+, and one P5+ atom. In the fourteenth S+1.60- site, S+1.60- is bonded in a distorted L-shaped geometry to one Nb5+, one Ag1+, and one P5+ atom. In the fifteenth S+1.60- site, S+1.60- is bonded in a 4-coordinate geometry to one K1+, two Nb5+, and one S+1.60- atom. The S–S bond length is 2.05 Å. In the sixteenth S+1.60- site, S+1.60- is bonded in a 4-coordinate geometry to one K1+, two Nb5+, and one S+1.60- atom. The S–S bond length is 2.05 Å. In the seventeenth S+1.60- site, S+1.60- is bonded in a 4-coordinate geometry to one K1+, two Nb5+, and one S+1.60- atom. In the eighteenth S+1.60- site, S+1.60- is bonded in a 4-coordinate geometry to one K1+, two Nb5+, and one S+1.60- atom. In the nineteenth S+1.60- site, S+1.60- is bonded in an L-shaped geometry to one Nb5+ and one P5+ atom. In the twentieth S+1.60- site, S+1.60- is bonded in a 2-coordinate geometry to one K1+, one Nb5+, and one P5+ atom.

36 MATERIALS SCIENCE↗

DOE OSTI2020

Optimized continuum x-ray emission from laser-generated plasma

We study continuum x-ray emission from hot plasma at the National Ignition Facility (NIF). We find that the x-ray yield in the multi-keV photon energy range is larger in Ti than in Ag or Au. This apparent paradox is due to Ti K-shell vacancies generated by the extraordinary energy density achieved by the NIF lasers. This is supported by direct observations of large continuum enhancement above the Ti K-series limit due to both free–bound (recombination) emission and strong Ly α (H-like) emission. Detailed calculations agree well with our measurements and support our conclusions.  X-ray emission from matter pervades the universe and plays an important role in the high-energy density (HED) regime (~10 5 J/cm 3 ). For example, the emission and absorption of x-rays controls the thermal state and evolution of stellar interiors.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗

DOE OSTI2022

Screening of bimetallic electrocatalysts for water purification with machine learning

Electrocatalysis provides a potential solution to NO 3 - pollution in wastewater by converting it to innocuous N 2 gas. However, materials with excellent catalytic activity are typically limited to expensive precious metals, hindering their commercial viability. Here, in response to this challenge, we have conducted the most extensive computational search to date for electrocatalysts that can facilitate NO 3 - reduction reaction, starting with 59 390 candidate bimetallic alloys from the Materials Project and Automatic-Flow databases. Using a joint machine learning- and computation-based screening strategy, we evaluated our candidates based on corrosion resistance, catalytic activity, N 2 selectivity, cost, and the ability to synthesize. We found that only 20 materials will satisfy all criteria in our screening strategy, all of which contain varying amounts of Cu. Our proposed list of candidates is consistent with previous materials investigated in the literature, with the exception of Cu–Co and Cu–Ag based compounds that merit further investigation.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

DOE OSTI2020

Materials Data on Y3AgO5 by Materials Project

Y3AgO5 is Aluminum carbonitride-like structured and crystallizes in the trigonal R3m space group. The structure is three-dimensional. there are three inequivalent Y3+ sites. In the first Y3+ site, Y3+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Y–O bond distances ranging from 2.25–2.44 Å. In the second Y3+ site, Y3+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Y–O bond distances ranging from 2.21–2.53 Å. In the third Y3+ site, Y3+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Y–O bond distances ranging from 2.18–2.55 Å. There are three inequivalent Ag1+ sites. In the first Ag1+ site, Ag1+ is bonded in a tetrahedral geometry to four O2- atoms. There are one shorter (2.29 Å) and three longer (2.33 Å) Ag–O bond lengths. In the second Ag1+ site, Ag1+ is bonded in a tetrahedral geometry to four O2- atoms. There are one shorter (2.14 Å) and three longer (2.22 Å) Ag–O bond lengths. In the third Ag1+ site, Ag1+ is bonded in a rectangular see-saw-like geometry to four O2- atoms. There are one shorter (2.27 Å) and three longer (2.31 Å) Ag–O bond lengths. There are nine inequivalent O2- sites. In the first O2- site, O2- is bonded to three equivalent Y3+ and one Ag1+ atom to form OY3Ag trigonal pyramids that share corners with three equivalent OY6 octahedra and corners with twelve OY3Ag tetrahedra. The corner-sharing octahedral tilt angles are 48°. In the second O2- site, O2- is bonded to three equivalent Y3+ and one Ag1+ atom to form distorted OY3Ag tetrahedra that share corners with twelve OY3Ag tetrahedra and a faceface with one OY6 octahedra. In the third O2- site, O2- is bonded to three equivalent Y3+ and one Ag1+ atom to form corner-sharing OY3Ag trigonal pyramids. In the fourth O2- site, O2- is bonded to six Y3+ atoms to form a mixture of distorted face and corner-sharing OY6 octahedra. In the fifth O2- site, O2- is bonded in a 3-coordinate geometry to three equivalent Y3+ atoms. In the sixth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to three equivalent Y3+ atoms. In the seventh O2- site, O2- is bonded to three Y3+ and one Ag1+ atom to form distorted OY3Ag tetrahedra that share corners with two equivalent OY6 octahedra, corners with ten OY3Ag tetrahedra, and corners with two OY3Ag trigonal pyramids. The corner-sharing octahedral tilt angles are 55°. In the eighth O2- site, O2- is bonded to three Y3+ and one Ag1+ atom to form OY3Ag tetrahedra that share a cornercorner with one OY6 octahedra, corners with nine OY3Ag tetrahedra, and corners with three OY3Ag trigonal pyramids. The corner-sharing octahedral tilt angles are 43°. In the ninth O2- site, O2- is bonded to three Y3+ and one Ag1+ atom to form distorted OY3Ag tetrahedra that share corners with nine OY3Ag tetrahedra, corners with three OY3Ag trigonal pyramids, and a faceface with one OY6 octahedra.

36 MATERIALS SCIENCE↗

NASA NTRS1993

TAB interconnects for space concentrator solar cell arrays

The Boeing Company has evaluated the use of Tape Automated Bonding (TAB) and Surface Mount Technology (SMT) for a highly reliable, low cost interconnect for concentrator solar cell arrays. TAB and SMT are currently used in the electronics industry for chip interconnects and printed circuit board assembly. TAB tape consists of sixty-four 3-mil/1-oz tin-plated copper leads on 8-mil centers. The leads are thermocompression gang bonded to GaAs concentrator solar cell with silver contacts. This bond, known as an Inner Lead Bond (ILB), allows for pretesting and sorting capability via nondestruct wire bond pull and flash testing. Destructive wire pull tests resulted in preferred mid-span failures. Improvements in fill factor were attributed to decreased contact resistance on TAB bonded cells. Preliminary thermal cycling and aging tests were shown excellent bond strength and metallurgical results. Auger scans of bond sites reveals an Ag-Cu-Tin composition. Improper bonds are identified through flash testing as a performance degradation. On going testing of cells are underway at Lewis Research Center. SMT techniques are utilized to excise and form TAB leads post ILB. The formed leads' shape isolates thermal mismatches between the cells and the flex circuit they are mounted on. TABed cells are picked and placed with a gantry x-y-z positioning system with pattern recognition. Adhesives are selected to avoid thermal expansion mismatch and promote thermal transfer to the flex circuit. TAB outer lead bonds are parallel gap welded (PGW) to the flex circuit to finish the concentrator solar cell subassembly.

Avery, J.↗

DOE OSTI2020

Materials Data on AgSb(Te8Pb7)2 by Materials Project

AgSb(Pb7Te8)2 is alpha Po-derived structured and crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Ag1+ is bonded to six Te2- atoms to form AgTe6 octahedra that share corners with two equivalent PbTe6 octahedra, corners with four equivalent SbTe6 octahedra, and edges with twelve PbTe6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are two shorter (2.98 Å) and four longer (3.36 Å) Ag–Te bond lengths. There are four inequivalent Pb2+ sites. In the first Pb2+ site, Pb2+ is bonded to six Te2- atoms to form a mixture of edge and corner-sharing PbTe6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are two shorter (3.22 Å) and four longer (3.27 Å) Pb–Te bond lengths. In the second Pb2+ site, Pb2+ is bonded to six Te2- atoms to form PbTe6 octahedra that share corners with six PbTe6 octahedra, edges with two equivalent AgTe6 octahedra, edges with two equivalent SbTe6 octahedra, and edges with eight equivalent PbTe6 octahedra. The corner-sharing octahedra tilt angles range from 0–3°. There are two shorter (3.23 Å) and four longer (3.27 Å) Pb–Te bond lengths. In the third Pb2+ site, Pb2+ is bonded to six Te2- atoms to form PbTe6 octahedra that share corners with six equivalent PbTe6 octahedra, an edgeedge with one AgTe6 octahedra, an edgeedge with one SbTe6 octahedra, and edges with ten PbTe6 octahedra. The corner-sharing octahedra tilt angles range from 0–8°. There are a spread of Pb–Te bond distances ranging from 3.20–3.28 Å. In the fourth Pb2+ site, Pb2+ is bonded to six Te2- atoms to form PbTe6 octahedra that share a cornercorner with one AgTe6 octahedra, a cornercorner with one SbTe6 octahedra, corners with four equivalent PbTe6 octahedra, and edges with twelve PbTe6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are four shorter (3.27 Å) and two longer (3.40 Å) Pb–Te bond lengths. Sb3+ is bonded to six Te2- atoms to form SbTe6 octahedra that share corners with two equivalent PbTe6 octahedra, corners with four equivalent AgTe6 octahedra, and edges with twelve PbTe6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are two shorter (3.11 Å) and four longer (3.17 Å) Sb–Te bond lengths. There are six inequivalent Te2- sites. In the first Te2- site, Te2- is bonded to six Pb2+ atoms to form a mixture of edge and corner-sharing TePb6 octahedra. The corner-sharing octahedra tilt angles range from 0–1°. In the second Te2- site, Te2- is bonded to six Pb2+ atoms to form a mixture of edge and corner-sharing TePb6 octahedra. The corner-sharing octahedra tilt angles range from 0–2°. In the third Te2- site, Te2- is bonded to one Ag1+, four Pb2+, and one Sb3+ atom to form TeAgSbPb4 octahedra that share corners with six TePb6 octahedra and edges with twelve TeAgSbPb4 octahedra. The corner-sharing octahedra tilt angles range from 0–2°. In the fourth Te2- site, Te2- is bonded to one Ag1+ and five Pb2+ atoms to form TeAgPb5 octahedra that share corners with six TeAgPb5 octahedra and edges with twelve TePb6 octahedra. The corner-sharing octahedra tilt angles range from 0–5°. In the fifth Te2- site, Te2- is bonded to five Pb2+ and one Sb3+ atom to form TeSbPb5 octahedra that share corners with six TeAgPb5 octahedra and edges with twelve TePb6 octahedra. The corner-sharing octahedra tilt angles range from 0–5°. In the sixth Te2- site, Te2- is bonded to one Ag1+, four Pb2+, and one Sb3+ atom to form TeAgSbPb4 octahedra that share corners with six TePb6 octahedra and edges with twelve TeAgSbPb4 octahedra. The corner-sharing octahedra tilt angles range from 0–2°. Both Te–Pb bond lengths are 3.20 Å.

36 MATERIALS SCIENCE↗

DOE OSTI2020

Materials Data on Al11AgO17 by Materials Project

AgAl11O17 crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. Ag1+ is bonded in a hexagonal planar geometry to six O2- atoms. There are four shorter (2.75 Å) and two longer (2.89 Å) Ag–O bond lengths. There are five inequivalent Al3+ sites. In the first Al3+ site, Al3+ is bonded to six O2- atoms to form AlO6 octahedra that share corners with five AlO4 tetrahedra and edges with five AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.82–2.03 Å. In the second Al3+ site, Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share corners with six AlO6 octahedra and a cornercorner with one AlO4 tetrahedra. The corner-sharing octahedra tilt angles range from 54–56°. There are a spread of Al–O bond distances ranging from 1.70–1.80 Å. In the third Al3+ site, Al3+ is bonded to four O2- atoms to form corner-sharing AlO4 tetrahedra. The corner-sharing octahedra tilt angles range from 54–58°. There is three shorter (1.82 Å) and one longer (1.83 Å) Al–O bond length. In the fourth Al3+ site, Al3+ is bonded to six O2- atoms to form AlO6 octahedra that share corners with five AlO4 tetrahedra and edges with five AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.82–2.07 Å. In the fifth Al3+ site, Al3+ is bonded to six O2- atoms to form AlO6 octahedra that share corners with six equivalent AlO4 tetrahedra and edges with six AlO6 octahedra. There is four shorter (1.91 Å) and two longer (1.92 Å) Al–O bond length. There are seven inequivalent O2- sites. In the first O2- site, O2- is bonded in a trigonal planar geometry to three Al3+ atoms. In the second O2- site, O2- is bonded in a rectangular see-saw-like geometry to four Al3+ atoms. In the third O2- site, O2- is bonded in a 3-coordinate geometry to one Ag1+ and three Al3+ atoms. In the fourth O2- site, O2- is bonded in a distorted linear geometry to two equivalent Ag1+ and two equivalent Al3+ atoms. In the fifth O2- site, O2- is bonded in a rectangular see-saw-like geometry to four Al3+ atoms. In the sixth O2- site, O2- is bonded in a rectangular see-saw-like geometry to four Al3+ atoms. In the seventh O2- site, O2- is bonded in a trigonal non-coplanar geometry to three Al3+ atoms.

36 MATERIALS SCIENCE↗

NASA NTRS1999

Multimodality stereotactic brain tissue identification: the NASA smart probe project

Real-time tissue identification can benefit procedures such as stereotactic brain biopsy, functional neurosurgery and brain tumor excision. Optical scattering spectroscopy has been shown to be effective at discriminating cancer from noncancerous conditions in the colon, bladder and breast. The NASA Smart Probe extends the concept of 'optical biopsy' by using neural network techniques to combine the output from 3 microsensors contained within a cannula 2. 7 mm in diameter (i.e. the diameter of a stereotactic brain biopsy needle). Experimental data from 5 rats show the clear differentiation between tissues such as brain, nerve, fat, artery and muscle that can be achieved with optical scattering spectroscopy alone. These data and previous findings with other modalities such as (1) analysis of the image from a fiberoptic neuroendoscope and (2) the output from a microstrain gauge suggest the Smart Probe multiple microsensor technique shows promise for real-time tissue identification in neurosurgical procedures. Copyright 2000 S. Karger AG, Basel.

Non-programmatic↗

DOE OSTI2025

Effect of MgSO 4 addition on alkali sulphates induced hot corrosion of a β-NiAl coating

The effect of MgSO 4 addition on alkali sulphates induced hot corrosion of a β-NiAl coating was studied by performing a series of tests with deposits of Na 2 SO 4 , Na 2 SO 4 -20 %K 2 SO 4 and Na 2 SO 4 -12 %K 2 SO 4 -35 %MgSO 4 (mol.% for all) at 700 °C in air with addition of SO 2 . For elucidating the observed corrosion phenomena, various salt-oxide/NiAl powder mixtures were exposed to the same hot corrosion test conditions. Two pseudo-binary phase diagrams of the Na, K, Mg-sulphate systems were calculated using an in-house developed thermodynamic database. Addition of MgSO 4 to Na 2 SO 4 -20 %K 2 SO 4 deposit salt inhibited the hot corrosion attack during 24 h exposure, which is related to consumption of aggressive K 2 SO 4 by the formation of solid K 2 Mg 2 (SO 4 ) 3 . However, extending the exposure with Na 2 SO 4 -12 %K 2 SO 4 -35 %MgSO 4 deposit to 100 h resulted in severe corrosion attack. The latter observation is explained by a reaction between K 2 Mg 2 (SO 4 ) 3 and NiAl causing formation of a Mg, Ni and Al containing spinel accompanied by release of the aggressive K 2 SO 4 into the liquid phase.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

DOE OSTI2025

Techno-economic evaluation of emission control configurations for AMP/PZ-based post-combustion CO 2 capture

Minimizing the environmental impacts of amine-based post-combustion carbon capture technologies is essential for regulatory compliance and public acceptance. Experimental campaigns at RWE's CO 2 capture pilot plant in Niederaussem using CESAR1 demonstrated that combining existing emission abatement technologies can substantially reduce the concentration of amines and degradation products in the CO 2 -depleted flue gas to below the detection limit of an infrared spectrometer. The campaign confirmed that a proprietary dry bed technology (OEASE aerozone™) or a second water wash can reduce AMP and PZ emissions to below 1 mg/Nm 3 . However, an acid or chemically active wash downstream of the water wash is necessary to reduce NH 3 emissions to very low levels (<2 mg/Nm 3 ). Combining a dry bed with an acid wash significantly reduces both the required acid solution and the resulting acid waste. The techno-economic analysis indicates that implementing emission mitigation technologies provides substantial environmental benefits for the CESAR1 process, with only a marginal increase (<1 €/tCO 2 ) in both the carbon capture cost (CCC) and CO 2 avoidance cost (CAC). The additional capital cost associated with extra column packing is offset by operational cost savings from reduced solvent losses. For stringent emission permits targeting NH 3 , a configuration combining a dry bed upstream of the water wash followed by an acid wash achieves the best balance between emission control and cost efficiency. This configuration results in a Levelized Cost of Electricity (LCOE) of 143 €/MWh, a CCC of 45.4 €/tCO 2 , and a CAC of 88.4 €/tCO 2 .

AMP↗

DOE OSTI2024

Overionized plasma in the supernova remnant Sagittarius A East anchored by XRISM observations

Sagittarius A East is a supernova remnant with a unique surrounding environment, as it is located in the immediate vicinity of the supermassive black hole at the Galactic center, Sagittarius A$^{*}$. The X-ray emission of the remnant is suspected to show features of overionized plasma, which would require peculiar evolutionary paths. We report on the first observation of Sagittarius A East with the X-Ray Imaging and Spectroscopy Mission (XRISM). Equipped with a combination of a high-resolution microcalorimeter spectrometer and a large field-of-view CCD imager, we for the first time resolved the Fe xxv K-shell lines into fine structure lines and measured the forbidden-to-resonance intensity ratio to be $1.39 \pm 0.12$, which strongly suggests the presence of overionized plasma. We obtained a reliable constraint on the ionization temperature just before the transition into the overionization state, of $\gt\! 4\:$keV. The recombination timescale was constrained to be $\lt\! 8 \times 10^{11} \:$cm$^{-3}\:$s. The small velocity dispersion of $109 \pm 6\:$km$\:$s$^{-1}$ indicates a low Fe ion temperature $\lt\! 8\:$keV and a small expansion velocity $\lt\! 200\:$km$\:$s$^{-1}$. The high initial ionization temperature and small recombination timescale suggest that either rapid cooling of the plasma via adiabatic expansion from dense circumstellar material or intense photoionization by Sagittarius A$^{*}$ in the past may have triggered the overionization.

galaxy center↗

DOE OSTI2020

Materials Data on AgH3CN3O4 by Materials Project

AgCN3H3O4 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are two inequivalent Ag2+ sites. In the first Ag2+ site, Ag2+ is bonded in a 7-coordinate geometry to two N+0.33- and five O2- atoms. There are one shorter (2.77 Å) and one longer (2.82 Å) Ag–N bond lengths. There are a spread of Ag–O bond distances ranging from 2.36–2.89 Å. In the second Ag2+ site, Ag2+ is bonded in a 4-coordinate geometry to one N+0.33- and three O2- atoms. The Ag–N bond length is 2.06 Å. There are one shorter (2.21 Å) and two longer (2.50 Å) Ag–O bond lengths. There are two inequivalent C4+ sites. In the first C4+ site, C4+ is bonded in a trigonal planar geometry to two N+0.33- and one O2- atom. There is one shorter (1.36 Å) and one longer (1.37 Å) C–N bond length. The C–O bond length is 1.26 Å. In the second C4+ site, C4+ is bonded in a trigonal planar geometry to two N+0.33- and one O2- atom. There is one shorter (1.34 Å) and one longer (1.37 Å) C–N bond length. The C–O bond length is 1.27 Å. There are six inequivalent N+0.33- sites. In the first N+0.33- site, N+0.33- is bonded in a 3-coordinate geometry to one Ag2+, one C4+, and two H1+ atoms. There is one shorter (1.02 Å) and one longer (1.03 Å) N–H bond length. In the second N+0.33- site, N+0.33- is bonded in a distorted trigonal planar geometry to one Ag2+, one C4+, and two H1+ atoms. Both N–H bond lengths are 1.02 Å. In the third N+0.33- site, N+0.33- is bonded in a distorted bent 120 degrees geometry to one Ag2+ and one C4+ atom. In the fourth N+0.33- site, N+0.33- is bonded in a trigonal planar geometry to one C4+ and two H1+ atoms. There is one shorter (1.02 Å) and one longer (1.03 Å) N–H bond length. In the fifth N+0.33- site, N+0.33- is bonded in a trigonal planar geometry to three O2- atoms. There is one shorter (1.25 Å) and two longer (1.28 Å) N–O bond length. In the sixth N+0.33- site, N+0.33- is bonded in a trigonal planar geometry to three O2- atoms. There are a spread of N–O bond distances ranging from 1.26–1.28 Å. There are six inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one N+0.33- atom. In the second H1+ site, H1+ is bonded in a single-bond geometry to one N+0.33- atom. In the third H1+ site, H1+ is bonded in a single-bond geometry to one N+0.33- atom. In the fourth H1+ site, H1+ is bonded in a single-bond geometry to one N+0.33- atom. In the fifth H1+ site, H1+ is bonded in a single-bond geometry to one N+0.33- atom. In the sixth H1+ site, H1+ is bonded in a single-bond geometry to one N+0.33- atom. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one Ag2+ and one N+0.33- atom. In the second O2- site, O2- is bonded in a distorted water-like geometry to one Ag2+ and one N+0.33- atom. In the third O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Ag2+ and one N+0.33- atom. In the fourth O2- site, O2- is bonded in a distorted water-like geometry to one Ag2+ and one N+0.33- atom. In the fifth O2- site, O2- is bonded in a distorted single-bond geometry to one Ag2+ and one N+0.33- atom. In the sixth O2- site, O2- is bonded in a distorted single-bond geometry to one Ag2+ and one N+0.33- atom. In the seventh O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Ag2+ and one C4+ atom. In the eighth O2- site, O2- is bonded in a distorted single-bond geometry to one Ag2+ and one C4+ atom.

36 MATERIALS SCIENCE↗

DOE OSTI2021

Allosteric binding properties of a 1,3-alternate thiacalix[4]arene-based receptor having phenylthiourea and 2-pyridylmethyl moieties on opposite faces

The synthesis of three new heteroditopic receptors (5a–c) which are based on thiacalix[4]arenes in the 1,3-alternate conformation is reported herein. These new receptors each have two thiourea moieties linking phenyl groups, two of which are substituted with electron-withdrawing groups at their para-positions, and at the opposite side of the thiacalix[4]arene cavity, with two 2-pyridylmethyl groups. One example (5a) was also characterized by X-ray crystallography. A limited 1 H-NMR and UV-vis anion complexation study was conducted. DFT computational determinations indicated that 5c, which has strongly electron-withdrawing NO 2 groups, had the most effective recognition ability towards the selected anions. The binding of Ag + at the 2-pyridyl moieties, and the binding of the anions at the two thiourea NH groups of the p-substituted phenylthioureido moieties, respectively, was also investigated. The appearance of a positive allosteric effect with receptor 5b was also found using 1 H-NMR titration experiments.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗