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At least 955 records · Page 53
All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Materials Data on Er(SiPt)2 by Materials Project

ErPt2Si2 crystallizes in the tetragonal P4/nmm space group. The structure is three-dimensional. Er is bonded in a 12-coordinate geometry to eight Pt and eight Si atoms. There are four shorter (3.19 Å) and four longer (3.27 Å) Er–Pt bond lengths. There are four shorter (3.17 Å) and four longer (3.22 Å) Er–Si bond lengths. There are two inequivalent Pt sites. In the first Pt site, Pt is bonded to four equivalent Er and four equivalent Si atoms to form distorted PtEr4Si4 tetrahedra that share corners with twelve equivalent SiEr4Pt4 tetrahedra, edges with two equivalent SiEr4Pt4 tetrahedra, edges with four equivalent PtEr4Si4 tetrahedra, and faces with four equivalent PtEr4Si4 tetrahedra. All Pt–Si bond lengths are 2.48 Å. In the second Pt site, Pt is bonded in a 9-coordinate geometry to four equivalent Er and five Si atoms. There are one shorter (2.37 Å) and four longer (2.43 Å) Pt–Si bond lengths. There are two inequivalent Si sites. In the first Si site, Si is bonded to four equivalent Er and four equivalent Pt atoms to form distorted SiEr4Pt4 tetrahedra that share corners with twelve equivalent PtEr4Si4 tetrahedra, edges with two equivalent PtEr4Si4 tetrahedra, edges with four equivalent SiEr4Pt4 tetrahedra, and faces with four equivalent SiEr4Pt4 tetrahedra. In the second Si site, Si is bonded in a 9-coordinate geometry to four equivalent Er and five Pt atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on MgPt7 by Materials Project

MgPt7 crystallizes in the cubic Fm-3m space group. The structure is three-dimensional. Mg2+ is bonded to twelve equivalent Pt+0.29- atoms to form MgPt12 cuboctahedra that share corners with twelve equivalent MgPt12 cuboctahedra and faces with six equivalent PtPt12 cuboctahedra. All Mg–Pt bond lengths are 2.81 Å. There are two inequivalent Pt+0.29- sites. In the first Pt+0.29- site, Pt+0.29- is bonded to twelve equivalent Pt+0.29- atoms to form PtPt12 cuboctahedra that share corners with twelve equivalent PtPt12 cuboctahedra and faces with six equivalent MgPt12 cuboctahedra. All Pt–Pt bond lengths are 2.81 Å. In the second Pt+0.29- site, Pt+0.29- is bonded in a distorted linear geometry to two equivalent Mg2+ and two equivalent Pt+0.29- atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Nd(GePt)2 by Materials Project

Nd(PtGe)2 crystallizes in the monoclinic P2_1 space group. The structure is three-dimensional. Nd is bonded in a 12-coordinate geometry to eight Pt and eight Ge atoms. There are a spread of Nd–Pt bond distances ranging from 3.29–3.44 Å. There are a spread of Nd–Ge bond distances ranging from 3.26–3.41 Å. There are two inequivalent Pt sites. In the first Pt site, Pt is bonded in a 9-coordinate geometry to four equivalent Nd and five Ge atoms. There are one shorter (2.47 Å) and four longer (2.53 Å) Pt–Ge bond lengths. In the second Pt site, Pt is bonded in a 4-coordinate geometry to four equivalent Nd and four equivalent Ge atoms. There are one shorter (2.56 Å) and three longer (2.57 Å) Pt–Ge bond lengths. There are two inequivalent Ge sites. In the first Ge site, Ge is bonded in a 9-coordinate geometry to four equivalent Nd and five Pt atoms. In the second Ge site, Ge is bonded in a 4-coordinate geometry to four equivalent Nd and four equivalent Pt atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Dy(GePt)2 by Materials Project

Dy(PtGe)2 crystallizes in the monoclinic P2_1 space group. The structure is three-dimensional. Dy is bonded in a 12-coordinate geometry to eight Pt and eight Ge atoms. There are a spread of Dy–Pt bond distances ranging from 3.21–3.35 Å. There are a spread of Dy–Ge bond distances ranging from 3.13–3.48 Å. There are two inequivalent Pt sites. In the first Pt site, Pt is bonded in a 9-coordinate geometry to four equivalent Dy and five Ge atoms. There are a spread of Pt–Ge bond distances ranging from 2.43–2.54 Å. In the second Pt site, Pt is bonded to four equivalent Dy and four equivalent Ge atoms to form distorted PtDy4Ge4 tetrahedra that share corners with twelve equivalent GeDy4Pt4 tetrahedra, edges with two equivalent GeDy4Pt4 tetrahedra, edges with four equivalent PtDy4Ge4 tetrahedra, and faces with four equivalent PtDy4Ge4 tetrahedra. There are a spread of Pt–Ge bond distances ranging from 2.55–2.57 Å. There are two inequivalent Ge sites. In the first Ge site, Ge is bonded in a 9-coordinate geometry to four equivalent Dy and five Pt atoms. In the second Ge site, Ge is bonded to four equivalent Dy and four equivalent Pt atoms to form distorted GeDy4Pt4 tetrahedra that share corners with twelve equivalent PtDy4Ge4 tetrahedra, edges with two equivalent PtDy4Ge4 tetrahedra, edges with four equivalent GeDy4Pt4 tetrahedra, and faces with four equivalent GeDy4Pt4 tetrahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Zr6Ga16Pt7 by Materials Project

Zr6Pt7Ga16 crystallizes in the cubic Fm-3m space group. The structure is three-dimensional. Zr is bonded in a 4-coordinate geometry to four equivalent Pt and eight Ga atoms. All Zr–Pt bond lengths are 3.22 Å. There are four shorter (2.87 Å) and four longer (3.20 Å) Zr–Ga bond lengths. There are two inequivalent Pt sites. In the first Pt site, Pt is bonded to four equivalent Zr and eight Ga atoms to form a mixture of distorted face and corner-sharing PtZr4Ga8 cuboctahedra. There are four shorter (2.56 Å) and four longer (2.75 Å) Pt–Ga bond lengths. In the second Pt site, Pt is bonded in a body-centered cubic geometry to eight equivalent Ga atoms. All Pt–Ga bond lengths are 2.61 Å. There are two inequivalent Ga sites. In the first Ga site, Ga is bonded in a 6-coordinate geometry to three equivalent Zr and three equivalent Pt atoms. In the second Ga site, Ga is bonded in a 4-coordinate geometry to three equivalent Zr and four Pt atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ca2AlP3Pt7 by Materials Project

Ca2Pt7AlP3 crystallizes in the tetragonal I-4m2 space group. The structure is three-dimensional. Ca2+ is bonded in a 4-coordinate geometry to nine Pt2- atoms. There are a spread of Ca–Pt bond distances ranging from 3.06–3.50 Å. There are four inequivalent Pt2- sites. In the first Pt2- site, Pt2- is bonded in a 12-coordinate geometry to two equivalent Ca2+, six Pt2-, two equivalent Al3+, and two equivalent P+2.33+ atoms. There are two shorter (2.79 Å) and four longer (2.86 Å) Pt–Pt bond lengths. Both Pt–Al bond lengths are 2.79 Å. Both Pt–P bond lengths are 2.45 Å. In the second Pt2- site, Pt2- is bonded in a 12-coordinate geometry to two equivalent Ca2+, six Pt2-, two equivalent Al3+, and two equivalent P+2.33+ atoms. Both Pt–Pt bond lengths are 2.84 Å. Both Pt–Al bond lengths are 2.84 Å. Both Pt–P bond lengths are 2.42 Å. In the third Pt2- site, Pt2- is bonded in a 7-coordinate geometry to five equivalent Ca2+ and three P+2.33+ atoms. There are one shorter (2.30 Å) and two longer (2.35 Å) Pt–P bond lengths. In the fourth Pt2- site, Pt2- is bonded to eight Pt2- and four equivalent Al3+ atoms to form distorted PtAl4Pt8 cuboctahedra that share corners with four equivalent PtAl4Pt8 cuboctahedra, faces with four equivalent PtAl4Pt8 cuboctahedra, and faces with four equivalent AlPt12 cuboctahedra. All Pt–Al bond lengths are 2.86 Å. Al3+ is bonded to twelve Pt2- atoms to form AlPt12 cuboctahedra that share corners with four equivalent AlPt12 cuboctahedra, faces with four equivalent PtAl4Pt8 cuboctahedra, and faces with four equivalent AlPt12 cuboctahedra. There are two inequivalent P+2.33+ sites. In the first P+2.33+ site, P+2.33+ is bonded in a 5-coordinate geometry to five Pt2- atoms. In the second P+2.33+ site, P+2.33+ is bonded to four equivalent Pt2- atoms to form corner-sharing PPt4 tetrahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on AlSiPt6 by Materials Project

Pt6SiAl crystallizes in the orthorhombic Cmmm space group. The structure is three-dimensional and consists of two aluminum molecules and one Pt6Si framework. In the Pt6Si framework, there are three inequivalent Pt+0.17+ sites. In the first Pt+0.17+ site, Pt+0.17+ is bonded in a linear geometry to two equivalent Si4- atoms. Both Pt–Si bond lengths are 2.77 Å. In the second Pt+0.17+ site, Pt+0.17+ is bonded in an L-shaped geometry to two equivalent Si4- atoms. Both Pt–Si bond lengths are 2.86 Å. In the third Pt+0.17+ site, Pt+0.17+ is bonded in an L-shaped geometry to two equivalent Si4- atoms. Both Pt–Si bond lengths are 2.68 Å. Si4- is bonded to twelve Pt+0.17+ atoms to form a mixture of face and corner-sharing SiPt12 cuboctahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Th(GePt)2 by Materials Project

Th(PtGe)2 crystallizes in the tetragonal P4/nmm space group. The structure is three-dimensional. Th is bonded in a 12-coordinate geometry to eight Pt and eight Ge atoms. There are four shorter (3.32 Å) and four longer (3.36 Å) Th–Pt bond lengths. There are four shorter (3.29 Å) and four longer (3.39 Å) Th–Ge bond lengths. There are two inequivalent Pt sites. In the first Pt site, Pt is bonded in a 4-coordinate geometry to four equivalent Th and four equivalent Ge atoms. All Pt–Ge bond lengths are 2.58 Å. In the second Pt site, Pt is bonded in a 9-coordinate geometry to four equivalent Th and five Ge atoms. There are one shorter (2.46 Å) and four longer (2.53 Å) Pt–Ge bond lengths. There are two inequivalent Ge sites. In the first Ge site, Ge is bonded in a 4-coordinate geometry to four equivalent Th and four equivalent Pt atoms. In the second Ge site, Ge is bonded in a 9-coordinate geometry to four equivalent Th and five Pt atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on MgPt2 by Materials Project

MgPt2 crystallizes in the hexagonal P-62m space group. The structure is three-dimensional. Mg is bonded to nine Pt atoms to form distorted MgPt9 cuboctahedra that share corners with fifteen equivalent MgPt9 cuboctahedra, corners with twenty-four PtMg6Pt6 cuboctahedra, edges with three equivalent PtMg6Pt6 cuboctahedra, and faces with five equivalent MgPt9 cuboctahedra. There are six shorter (2.80 Å) and three longer (2.84 Å) Mg–Pt bond lengths. There are two inequivalent Pt sites. In the first Pt site, Pt is bonded to six equivalent Mg and six equivalent Pt atoms to form distorted PtMg6Pt6 cuboctahedra that share corners with twelve equivalent MgPt9 cuboctahedra, corners with twelve equivalent PtMg4Pt2 cuboctahedra, edges with six equivalent MgPt9 cuboctahedra, edges with eighteen PtMg6Pt6 cuboctahedra, and faces with two equivalent PtMg6Pt6 cuboctahedra. All Pt–Pt bond lengths are 2.80 Å. In the second Pt site, Pt is bonded to four equivalent Mg and two equivalent Pt atoms to form distorted PtMg4Pt2 cuboctahedra that share corners with twelve equivalent MgPt9 cuboctahedra, corners with sixteen PtMg6Pt6 cuboctahedra, edges with ten PtMg6Pt6 cuboctahedra, and faces with two equivalent PtMg4Pt2 cuboctahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on VPt8 by Materials Project

Pt8V crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. V5+ is bonded to twelve Pt+0.62- atoms to form VPt12 cuboctahedra that share corners with eight equivalent PtV2Pt10 cuboctahedra, faces with two equivalent VPt12 cuboctahedra, and faces with twelve equivalent PtV2Pt10 cuboctahedra. There are eight shorter (2.74 Å) and four longer (2.75 Å) V–Pt bond lengths. There are two inequivalent Pt+0.62- sites. In the first Pt+0.62- site, Pt+0.62- is bonded to two equivalent V5+ and ten Pt+0.62- atoms to form distorted PtV2Pt10 cuboctahedra that share corners with two equivalent VPt12 cuboctahedra, corners with four equivalent PtV2Pt10 cuboctahedra, edges with twelve equivalent PtV2Pt10 cuboctahedra, faces with three equivalent VPt12 cuboctahedra, and faces with seven equivalent PtV2Pt10 cuboctahedra. There are a spread of Pt–Pt bond distances ranging from 2.70–2.89 Å. In the second Pt+0.62- site, Pt+0.62- is bonded in a distorted single-bond geometry to one V5+ and six equivalent Pt+0.62- atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Eu2(AsPt)3 by Materials Project

Eu2(PtAs)3 crystallizes in the tetragonal P4/mmm space group. The structure is one-dimensional and consists of one Eu2(PtAs)3 ribbon oriented in the (0, 0, 1) direction. Eu+2.50+ is bonded in a linear geometry to one Pt+1.33+ and one As3- atom. The Eu–Pt bond length is 2.62 Å. The Eu–As bond length is 2.91 Å. There are two inequivalent Pt+1.33+ sites. In the first Pt+1.33+ site, Pt+1.33+ is bonded in a linear geometry to one Eu+2.50+ and one As3- atom. The Pt–As bond length is 2.32 Å. In the second Pt+1.33+ site, Pt+1.33+ is bonded in a linear geometry to two equivalent As3- atoms. Both Pt–As bond lengths are 2.25 Å. There are two inequivalent As3- sites. In the first As3- site, As3- is bonded in a linear geometry to two equivalent Pt+1.33+ atoms. In the second As3- site, As3- is bonded in a linear geometry to one Eu+2.50+ and one Pt+1.33+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Pr(GePt)2 by Materials Project

Pr(PtGe)2 crystallizes in the monoclinic P2_1 space group. The structure is three-dimensional. Pr is bonded in a 12-coordinate geometry to eight Pt and eight Ge atoms. There are a spread of Pr–Pt bond distances ranging from 3.30–3.44 Å. There are a spread of Pr–Ge bond distances ranging from 3.27–3.42 Å. There are two inequivalent Pt sites. In the first Pt site, Pt is bonded in a 9-coordinate geometry to four equivalent Pr and five Ge atoms. There are one shorter (2.48 Å) and four longer (2.53 Å) Pt–Ge bond lengths. In the second Pt site, Pt is bonded in a 4-coordinate geometry to four equivalent Pr and four equivalent Ge atoms. There are a spread of Pt–Ge bond distances ranging from 2.56–2.58 Å. There are two inequivalent Ge sites. In the first Ge site, Ge is bonded in a 9-coordinate geometry to four equivalent Pr and five Pt atoms. In the second Ge site, Ge is bonded in a 4-coordinate geometry to four equivalent Pr and four equivalent Pt atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2025

Phase-Dependent Structure Sensitivity of Pt/TiO 2 for CO Oxidation Reactions

Here, in this study, we investigated the effect of the support (rutile vs anatase titania) and of the Pt size of Pt nanoparticles and supports (rutile vs anatase) in the CO oxidation reaction. The steady-state specific activity of Pt/Rutile gradually increases with Pt dispersion, while that of Pt/Anatase is invariant with respect to Pt dispersion and is lower than the activity of Pt/Rutile. Our kinetic studies demonstrated that the reaction order for CO based on steady state is positive for sub-nm Pt clusters stabilized on rutile titania and it gradually changes to zero for large Pt clusters (>1 nm), as known in agreement with other studies for for supported Pt catalysts. In contrast, Pt/Anatase catalysts always show zero order dependence irrespective of Pt the size of Pt nanoparticles. Scanning transmission electron microscopy (STEM), X-ray photoelectron spectroscopy (XPS) and CO chemisorption results confirm that the notable sintering of sub-nm Pt clusters supported on anatase occurs with time-on-stream, which we correlate with might be related with the change of the CO reaction order from positive (order initially) tobut zero order for larger particles after sintered states. On the contrary, Pt/Rutile does not show serious sintering during the reaction, and it shows positive reaction order even during the steady state. Thus Pt/Rutile shows positive order at steady state and higher specific activity. Our study reveals the origin of profound catalytic differences between Pt nanoparticles supported on anatase and rutile titania and highlights better stability and activity of Pt/Rutile catalysts. than Pt/Anatase due to its better stability.

Kim, Haneul [Ulsan National Institute of Science a↗
DOE OSTI2020

Materials Data on LaSnPt by Materials Project

LaPtSn crystallizes in the hexagonal P-62m space group. The structure is three-dimensional. La is bonded in a 11-coordinate geometry to five Pt and six equivalent Sn atoms. There are four shorter (3.14 Å) and one longer (3.20 Å) La–Pt bond lengths. There are two shorter (3.35 Å) and four longer (3.49 Å) La–Sn bond lengths. There are two inequivalent Pt sites. In the first Pt site, Pt is bonded in a 9-coordinate geometry to six equivalent La and three equivalent Sn atoms. All Pt–Sn bond lengths are 2.96 Å. In the second Pt site, Pt is bonded in a 9-coordinate geometry to three equivalent La and six equivalent Sn atoms. All Pt–Sn bond lengths are 2.85 Å. Sn is bonded in a 10-coordinate geometry to six equivalent La and four Pt atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Sc5Si7Pt9 by Materials Project

Sc5Pt9Si7 crystallizes in the hexagonal P-6 space group. The structure is three-dimensional. there are three inequivalent Sc+2.80+ sites. In the first Sc+2.80+ site, Sc+2.80+ is bonded in a 9-coordinate geometry to nine Pt2- atoms. There are six shorter (3.23 Å) and three longer (3.33 Å) Sc–Pt bond lengths. In the second Sc+2.80+ site, Sc+2.80+ is bonded in a 6-coordinate geometry to nine Pt2- atoms. There are six shorter (3.12 Å) and three longer (3.43 Å) Sc–Pt bond lengths. In the third Sc+2.80+ site, Sc+2.80+ is bonded in a 7-coordinate geometry to seven Pt2- atoms. There are a spread of Sc–Pt bond distances ranging from 2.92–3.04 Å. There are three inequivalent Pt2- sites. In the first Pt2- site, Pt2- is bonded in a 4-coordinate geometry to four Sc+2.80+, two equivalent Pt2-, and four Si+0.57+ atoms. Both Pt–Pt bond lengths are 2.87 Å. There are a spread of Pt–Si bond distances ranging from 2.36–2.48 Å. In the second Pt2- site, Pt2- is bonded in a 2-coordinate geometry to four Sc+2.80+, one Pt2-, and four Si+0.57+ atoms. The Pt–Pt bond length is 2.84 Å. There are a spread of Pt–Si bond distances ranging from 2.36–2.80 Å. In the third Pt2- site, Pt2- is bonded in a 12-coordinate geometry to five Sc+2.80+, three Pt2-, and four Si+0.57+ atoms. There are three shorter (2.48 Å) and one longer (2.53 Å) Pt–Si bond lengths. There are three inequivalent Si+0.57+ sites. In the first Si+0.57+ site, Si+0.57+ is bonded in a 6-coordinate geometry to six Pt2- atoms. In the second Si+0.57+ site, Si+0.57+ is bonded in a 5-coordinate geometry to five Pt2- atoms. In the third Si+0.57+ site, Si+0.57+ is bonded in a trigonal planar geometry to three equivalent Pt2- atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on ScSnPt by Materials Project

ScPtSn crystallizes in the hexagonal P-62c space group. The structure is three-dimensional. Sc is bonded in a 11-coordinate geometry to five Pt and six equivalent Sn atoms. There are a spread of Sc–Pt bond distances ranging from 2.87–3.05 Å. There are a spread of Sc–Sn bond distances ranging from 3.10–3.27 Å. There are two inequivalent Pt sites. In the first Pt site, Pt is bonded in a 9-coordinate geometry to three equivalent Sc and six equivalent Sn atoms. All Pt–Sn bond lengths are 2.75 Å. In the second Pt site, Pt is bonded in a 9-coordinate geometry to six equivalent Sc and three equivalent Sn atoms. All Pt–Sn bond lengths are 2.75 Å. Sn is bonded in a 10-coordinate geometry to six equivalent Sc and four Pt atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on YInPt by Materials Project

YPtIn crystallizes in the hexagonal P-62m space group. The structure is three-dimensional. Y is bonded in a 11-coordinate geometry to five Pt and six equivalent In atoms. There are four shorter (3.04 Å) and one longer (3.15 Å) Y–Pt bond lengths. There are two shorter (3.22 Å) and four longer (3.37 Å) Y–In bond lengths. There are two inequivalent Pt sites. In the first Pt site, Pt is bonded in a 9-coordinate geometry to three equivalent Y and six equivalent In atoms. All Pt–In bond lengths are 2.79 Å. In the second Pt site, Pt is bonded in a 9-coordinate geometry to six equivalent Y and three equivalent In atoms. All Pt–In bond lengths are 2.90 Å. In is bonded in a 10-coordinate geometry to six equivalent Y and four Pt atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on PrSnPt by Materials Project

PrPtSn crystallizes in the hexagonal P-62m space group. The structure is three-dimensional. Pr is bonded in a 11-coordinate geometry to five Pt and six equivalent Sn atoms. There are four shorter (3.12 Å) and one longer (3.15 Å) Pr–Pt bond lengths. There are two shorter (3.32 Å) and four longer (3.46 Å) Pr–Sn bond lengths. There are two inequivalent Pt sites. In the first Pt site, Pt is bonded in a 9-coordinate geometry to six equivalent Pr and three equivalent Sn atoms. All Pt–Sn bond lengths are 2.92 Å. In the second Pt site, Pt is bonded in a 9-coordinate geometry to three equivalent Pr and six equivalent Sn atoms. All Pt–Sn bond lengths are 2.85 Å. Sn is bonded in a 10-coordinate geometry to six equivalent Pr and four Pt atoms.

36 MATERIALS SCIENCE↗