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At least 631 records · Page 35
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DOE OSTI2020

Materials Data on ZrRh by Materials Project

ZrRh crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. there are two inequivalent Zr sites. In the first Zr site, Zr is bonded in a body-centered cubic geometry to eight Rh atoms. There are a spread of Zr–Rh bond distances ranging from 2.71–2.89 Å. In the second Zr site, Zr is bonded in a 5-coordinate geometry to seven Rh atoms. There are a spread of Zr–Rh bond distances ranging from 2.70–3.22 Å. There are two inequivalent Rh sites. In the first Rh site, Rh is bonded in a 7-coordinate geometry to seven Zr atoms. In the second Rh site, Rh is bonded in a 8-coordinate geometry to eight Zr atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on NbRh by Materials Project

NbRh is Tetraauricupride-like structured and crystallizes in the monoclinic P2/m space group. The structure is three-dimensional. there are two inequivalent Nb sites. In the first Nb site, Nb is bonded in a 12-coordinate geometry to eight Rh atoms. There are a spread of Nb–Rh bond distances ranging from 2.76–2.88 Å. In the second Nb site, Nb is bonded to eight Rh atoms to form a mixture of distorted edge, corner, and face-sharing NbRh8 cuboctahedra. There are four shorter (2.80 Å) and four longer (2.84 Å) Nb–Rh bond lengths. There are two inequivalent Rh sites. In the first Rh site, Rh is bonded to eight Nb atoms to form a mixture of distorted edge, corner, and face-sharing RhNb8 cuboctahedra. In the second Rh site, Rh is bonded in a 12-coordinate geometry to eight Nb atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Te4Rh3 by Materials Project

Rh3Te4 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are two inequivalent Rh sites. In the first Rh site, Rh is bonded to six Te atoms to form a mixture of distorted edge, face, and corner-sharing RhTe6 octahedra. The corner-sharing octahedra tilt angles range from 49–55°. There are four shorter (2.71 Å) and two longer (2.77 Å) Rh–Te bond lengths. In the second Rh site, Rh is bonded to six Te atoms to form a mixture of distorted edge, face, and corner-sharing RhTe6 octahedra. The corner-sharing octahedra tilt angles range from 49–55°. There are a spread of Rh–Te bond distances ranging from 2.64–2.78 Å. There are two inequivalent Te sites. In the first Te site, Te is bonded in a 5-coordinate geometry to five Rh atoms. In the second Te site, Te is bonded to four Rh atoms to form a mixture of distorted edge and corner-sharing TeRh4 trigonal pyramids.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on HfZr(SbRh)2 by Materials Project

HfZr(RhSb)2 is half-Heusler-derived structured and crystallizes in the trigonal R3m space group. The structure is three-dimensional. Hf is bonded in a body-centered cubic geometry to four Rh and four Sb atoms. There are one shorter (2.74 Å) and three longer (2.82 Å) Hf–Rh bond lengths. There are one shorter (2.80 Å) and three longer (2.81 Å) Hf–Sb bond lengths. Zr is bonded in a body-centered cubic geometry to four Rh and four Sb atoms. There are one shorter (2.82 Å) and three longer (2.84 Å) Zr–Rh bond lengths. There are three shorter (2.83 Å) and one longer (2.85 Å) Zr–Sb bond lengths. There are two inequivalent Rh sites. In the first Rh site, Rh is bonded to one Hf and three equivalent Zr atoms to form distorted RhHfZr3 tetrahedra that share corners with four equivalent SbHfZr3 tetrahedra, corners with twelve RhHfZr3 tetrahedra, and edges with six SbHf3Zr tetrahedra. In the second Rh site, Rh is bonded to three equivalent Hf and one Zr atom to form distorted RhHf3Zr tetrahedra that share corners with four equivalent SbHf3Zr tetrahedra, corners with twelve RhHfZr3 tetrahedra, and edges with six SbHf3Zr tetrahedra. There are two inequivalent Sb sites. In the first Sb site, Sb is bonded to three equivalent Hf and one Zr atom to form distorted SbHf3Zr tetrahedra that share corners with four equivalent RhHf3Zr tetrahedra, corners with twelve SbHf3Zr tetrahedra, and edges with six RhHfZr3 tetrahedra. In the second Sb site, Sb is bonded to one Hf and three equivalent Zr atoms to form distorted SbHfZr3 tetrahedra that share corners with four equivalent RhHfZr3 tetrahedra, corners with twelve SbHf3Zr tetrahedra, and edges with six RhHfZr3 tetrahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Sr8Rh5 by Materials Project

Sr8Rh5 crystallizes in the cubic Pm-3m space group. The structure is three-dimensional. Sr is bonded in a 5-coordinate geometry to five Rh atoms. There are a spread of Sr–Rh bond distances ranging from 3.15–3.18 Å. There are three inequivalent Rh sites. In the first Rh site, Rh is bonded in a body-centered cubic geometry to eight equivalent Sr atoms. In the second Rh site, Rh is bonded in a body-centered cubic geometry to eight equivalent Sr atoms. In the third Rh site, Rh is bonded in a body-centered cubic geometry to eight equivalent Sr atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Hf6Ga16Rh7 by Materials Project

Hf6Rh7Ga16 crystallizes in the cubic Fm-3m space group. The structure is three-dimensional. Hf is bonded in a 4-coordinate geometry to four equivalent Ga atoms. All Hf–Ga bond lengths are 2.77 Å. There are two inequivalent Rh sites. In the first Rh site, Rh is bonded to eight Ga atoms to form distorted edge-sharing RhGa8 cuboctahedra. There are four shorter (2.53 Å) and four longer (2.70 Å) Rh–Ga bond lengths. In the second Rh site, Rh is bonded in a body-centered cubic geometry to eight equivalent Ga atoms. All Rh–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 Hf and three equivalent Rh atoms. In the second Ga site, Ga is bonded in a 4-coordinate geometry to four Rh atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Yb5In4Cu20Rh by Materials Project

Yb5RhCu20In4 crystallizes in the trigonal R3m space group. The structure is three-dimensional. there are five inequivalent Yb sites. In the first Yb site, Yb is bonded in a 1-coordinate geometry to one Rh, twelve Cu, and three equivalent In atoms. The Yb–Rh bond length is 2.93 Å. There are a spread of Yb–Cu bond distances ranging from 2.91–3.04 Å. All Yb–In bond lengths are 3.14 Å. In the second Yb site, Yb is bonded in a 12-coordinate geometry to twelve Cu and four In atoms. There are a spread of Yb–Cu bond distances ranging from 2.94–2.98 Å. There are one shorter (3.05 Å) and three longer (3.10 Å) Yb–In bond lengths. In the third Yb site, Yb is bonded in a 12-coordinate geometry to twelve Cu and four In atoms. There are a spread of Yb–Cu bond distances ranging from 2.93–2.97 Å. There are one shorter (3.07 Å) and three longer (3.10 Å) Yb–In bond lengths. In the fourth Yb site, Yb is bonded in a 9-coordinate geometry to three equivalent Rh, twelve Cu, and one In atom. All Yb–Rh bond lengths are 3.07 Å. There are a spread of Yb–Cu bond distances ranging from 2.83–3.00 Å. The Yb–In bond length is 3.15 Å. In the fifth Yb site, Yb is bonded in a 12-coordinate geometry to twelve Cu and four In atoms. There are a spread of Yb–Cu bond distances ranging from 2.96–2.98 Å. There are one shorter (3.06 Å) and three longer (3.11 Å) Yb–In bond lengths. Rh is bonded in a 1-coordinate geometry to four Yb and twelve Cu atoms. There are a spread of Rh–Cu bond distances ranging from 2.90–2.97 Å. There are ten inequivalent Cu sites. In the first Cu site, Cu is bonded to three equivalent Yb, six Cu, and three equivalent In atoms to form CuYb3In3Cu6 cuboctahedra that share corners with eighteen CuYb3In3Cu6 cuboctahedra, edges with six equivalent CuYb3In3Cu6 cuboctahedra, and faces with eighteen CuYb3In2Cu6Rh cuboctahedra. There are three shorter (2.50 Å) and three longer (2.53 Å) Cu–Cu bond lengths. All Cu–In bond lengths are 2.97 Å. In the second Cu site, Cu is bonded to three equivalent Yb, six Cu, and three equivalent In atoms to form a mixture of corner, edge, and face-sharing CuYb3In3Cu6 cuboctahedra. There are three shorter (2.50 Å) and three longer (2.51 Å) Cu–Cu bond lengths. All Cu–In bond lengths are 2.97 Å. In the third Cu site, Cu is bonded to three equivalent Yb, six Cu, and three equivalent In atoms to form a mixture of corner, edge, and face-sharing CuYb3In3Cu6 cuboctahedra. There are three shorter (2.50 Å) and three longer (2.52 Å) Cu–Cu bond lengths. All Cu–In bond lengths are 2.97 Å. In the fourth Cu site, Cu is bonded to three equivalent Yb, six Cu, and three equivalent In atoms to form a mixture of corner, edge, and face-sharing CuYb3In3Cu6 cuboctahedra. There are three shorter (2.50 Å) and three longer (2.53 Å) Cu–Cu bond lengths. All Cu–In bond lengths are 2.97 Å. In the fifth Cu site, Cu is bonded to three equivalent Yb, three equivalent Rh, and six Cu atoms to form CuYb3Cu6Rh3 cuboctahedra that share corners with eighteen CuYb3In3Cu6 cuboctahedra, edges with six equivalent CuYb3Cu6Rh3 cuboctahedra, and faces with eighteen CuYb3In2Cu6Rh cuboctahedra. There are three shorter (2.48 Å) and three longer (2.49 Å) Cu–Cu bond lengths. In the sixth Cu site, Cu is bonded to three Yb, one Rh, six Cu, and two equivalent In atoms to form CuYb3In2Cu6Rh cuboctahedra that share corners with eighteen CuYb3In3Cu6 cuboctahedra, edges with six CuYb3In2Cu6Rh cuboctahedra, and faces with eighteen CuYb3In3Cu6 cuboctahedra. There are two shorter (2.52 Å) and two longer (2.56 Å) Cu–Cu bond lengths. Both Cu–In bond lengths are 2.97 Å. In the seventh Cu site, Cu is bonded to three Yb, six Cu, and three In atoms to form CuYb3In3Cu6 cuboctahedra that share corners with eighteen CuYb3In3Cu6 cuboctahedra, edges with six CuYb3In2Cu6Rh cuboctahedra, and faces with eighteen CuYb3In3Cu6 cuboctahedra. All Cu–Cu bond lengths are 2.54 Å. There are one shorter (2.94 Å) and two longer (2.97 Å) Cu–In bond lengths. In the eighth Cu site, Cu is bonded to three Yb, six Cu, and three In atoms to form a mixture of corner, edge, and face-sharing CuYb3In3Cu6 cuboctahedra. There are two shorter (2.53 Å) and two longer (2.54 Å) Cu–Cu bond lengths. There are one shorter (2.93 Å) and two longer (2.96 Å) Cu–In bond lengths. In the ninth Cu site, Cu is bonded to three Yb, six Cu, and three In atoms to form a mixture of corner, edge, and face-sharing CuYb3In3Cu6 cuboctahedra. All Cu–Cu bond lengths are 2.54 Å. There are one shorter (2.94 Å) and two longer (2.96 Å) Cu–In bond lengths. In the tenth Cu site, Cu is bonded to three Yb, two equivalent Rh, six Cu, and one In atom to form CuYb3InCu6Rh2 cuboctahedra that share corners with eighteen CuYb3In3Cu6 cuboctahedra, edges with six CuYb3In2Cu6Rh cuboctahedra, and faces with eighteen CuYb3In3Cu6 cuboctahedra. There are two shorter (2.53 Å) and two longer (2.54 Å) Cu–Cu bond lengths. The Cu–In bond length is 2.95 Å. There are four inequivalent In sites. In the first In site, In is bonded in a 4-coordinate geometry to four Yb and twelve Cu atoms. In the second In site, In is bonded in a 4-coordinate geometry to four Yb and twelve Cu atoms. In the third In site, In is bonded in a 4-coordinate geometry to four Yb and twelve Cu atoms. In the fourth In site, In is bonded in a 4-coordinate geometry to four Yb and twelve Cu atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on NbRh by Materials Project

NbRh is Tetraauricupride-like structured and crystallizes in the orthorhombic Pmma space group. The structure is three-dimensional. there are two inequivalent Nb sites. In the first Nb site, Nb is bonded to eight Rh atoms to form a mixture of distorted face, edge, and corner-sharing NbRh8 cuboctahedra. There are six shorter (2.80 Å) and two longer (2.85 Å) Nb–Rh bond lengths. In the second Nb site, Nb is bonded to eight Rh atoms to form a mixture of distorted face, edge, and corner-sharing NbRh8 cuboctahedra. There are a spread of Nb–Rh bond distances ranging from 2.79–2.83 Å. There are two inequivalent Rh sites. In the first Rh site, Rh is bonded to eight Nb atoms to form a mixture of distorted face, edge, and corner-sharing RhNb8 cuboctahedra. In the second Rh site, Rh is bonded to eight Nb atoms to form a mixture of distorted face, edge, and corner-sharing RhNb8 cuboctahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on LaNi3Rh2 by Materials Project

LaRh2Ni3 crystallizes in the orthorhombic Cmmm space group. The structure is three-dimensional. La is bonded in a 6-coordinate geometry to eight equivalent Rh and ten Ni atoms. All La–Rh bond lengths are 3.27 Å. There are a spread of La–Ni bond distances ranging from 3.00–3.35 Å. Rh is bonded to four equivalent La, two equivalent Rh, and six Ni atoms to form distorted RhLa4Ni6Rh2 cuboctahedra that share corners with four equivalent NiLa4Ni4Rh4 cuboctahedra, corners with twelve equivalent RhLa4Ni6Rh2 cuboctahedra, edges with four equivalent NiLa4Ni4Rh4 cuboctahedra, edges with six equivalent RhLa4Ni6Rh2 cuboctahedra, faces with four equivalent NiLa4Ni4Rh4 cuboctahedra, and faces with six equivalent RhLa4Ni6Rh2 cuboctahedra. Both Rh–Rh bond lengths are 2.66 Å. All Rh–Ni bond lengths are 2.56 Å. There are two inequivalent Ni sites. In the first Ni site, Ni is bonded in a 12-coordinate geometry to three equivalent La, four equivalent Rh, and two equivalent Ni atoms. Both Ni–Ni bond lengths are 2.45 Å. In the second Ni site, Ni is bonded to four equivalent La, four equivalent Rh, and four equivalent Ni atoms to form distorted NiLa4Ni4Rh4 cuboctahedra that share corners with eight equivalent RhLa4Ni6Rh2 cuboctahedra, corners with eight equivalent NiLa4Ni4Rh4 cuboctahedra, edges with two equivalent NiLa4Ni4Rh4 cuboctahedra, edges with eight equivalent RhLa4Ni6Rh2 cuboctahedra, faces with two equivalent NiLa4Ni4Rh4 cuboctahedra, and faces with eight equivalent RhLa4Ni6Rh2 cuboctahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on NiBi6Rh by Materials Project

RhNiBi6 crystallizes in the orthorhombic Pmc2_1 space group. The structure is one-dimensional and consists of two RhNiBi6 ribbons oriented in the (1, 0, 0) direction. Rh is bonded in a 9-coordinate geometry to two equivalent Ni and seven Bi atoms. Both Rh–Ni bond lengths are 2.76 Å. There are a spread of Rh–Bi bond distances ranging from 2.79–2.83 Å. Ni is bonded in a 9-coordinate geometry to two equivalent Rh and seven Bi atoms. There are a spread of Ni–Bi bond distances ranging from 2.71–2.93 Å. There are six inequivalent Bi sites. In the first Bi site, Bi is bonded in a 3-coordinate geometry to two equivalent Rh and one Ni atom. In the second Bi site, Bi is bonded in a 3-coordinate geometry to one Rh and two equivalent Ni atoms. In the third Bi site, Bi is bonded in a 2-coordinate geometry to two equivalent Rh and one Ni atom. In the fourth Bi site, Bi is bonded in a 3-coordinate geometry to one Rh and two equivalent Ni atoms. In the fifth Bi site, Bi is bonded in a distorted single-bond geometry to one Ni atom. In the sixth Bi site, Bi is bonded in a single-bond geometry to one Rh atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on CeMgRh by Materials Project

MgCeRh crystallizes in the hexagonal P-62m space group. The structure is three-dimensional. Mg is bonded in a 4-coordinate geometry to four Rh atoms. There are two shorter (2.71 Å) and two longer (2.88 Å) Mg–Rh bond lengths. Ce is bonded in a 5-coordinate geometry to five Rh atoms. There are four shorter (3.02 Å) and one longer (3.09 Å) Ce–Rh bond lengths. There are two inequivalent Rh sites. In the first Rh site, Rh is bonded in a 9-coordinate geometry to six equivalent Mg and three equivalent Ce atoms. In the second Rh site, Rh is bonded in a 9-coordinate geometry to three equivalent Mg and six equivalent Ce atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ce4SiRh12 by Materials Project

Ce4Rh12Si crystallizes in the cubic Im-3m space group. The structure is three-dimensional. Ce is bonded to twelve Rh atoms to form CeRh12 cuboctahedra that share corners with twelve equivalent CeRh12 cuboctahedra, faces with six equivalent CeRh12 cuboctahedra, and faces with two equivalent SiRh6 octahedra. There are six shorter (2.94 Å) and six longer (2.95 Å) Ce–Rh bond lengths. There are two inequivalent Rh sites. In the first Rh site, Rh is bonded in a distorted square co-planar geometry to four equivalent Ce atoms. In the second Rh site, Rh is bonded in a 5-coordinate geometry to four equivalent Ce and one Si atom. The Rh–Si bond length is 2.32 Å. Si is bonded to six equivalent Rh atoms to form SiRh6 octahedra that share faces with eight equivalent CeRh12 cuboctahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on HfGeRh by Materials Project

HfRhGe crystallizes in the hexagonal P-62m space group. The structure is three-dimensional. Hf is bonded in a 11-coordinate geometry to six equivalent Rh and five Ge atoms. There are two shorter (2.94 Å) and four longer (3.13 Å) Hf–Rh bond lengths. There are four shorter (2.79 Å) and one longer (2.80 Å) Hf–Ge bond lengths. Rh is bonded in a 12-coordinate geometry to six equivalent Hf, two equivalent Rh, and four Ge atoms. Both Rh–Rh bond lengths are 2.86 Å. There are two shorter (2.54 Å) and two longer (2.56 Å) Rh–Ge bond lengths. There are two inequivalent Ge sites. In the first Ge site, Ge is bonded in a 9-coordinate geometry to six equivalent Hf and three equivalent Rh atoms. In the second Ge site, Ge is bonded in a 9-coordinate geometry to three equivalent Hf and six equivalent Rh atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on NbRh2 by Materials Project

NbRh2 crystallizes in the monoclinic P2/m space group. The structure is three-dimensional. Nb is bonded in a 12-coordinate geometry to nine Rh atoms. There are a spread of Nb–Rh bond distances ranging from 2.74–2.80 Å. There are three inequivalent Rh sites. In the first Rh site, Rh is bonded to six equivalent Nb atoms to form a mixture of distorted corner, edge, and face-sharing RhNb6 cuboctahedra. In the second Rh site, Rh is bonded to four equivalent Nb atoms to form a mixture of distorted corner and edge-sharing RhNb4 cuboctahedra. In the third Rh site, Rh is bonded in a distorted linear geometry to two equivalent Nb atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ti2FeB2Ru4Rh by Materials Project

Ti2Ru4FeRhB2 crystallizes in the monoclinic P2/m space group. The structure is three-dimensional. there are two inequivalent Ti sites. In the first Ti site, Ti is bonded in a 12-coordinate geometry to eight Ru, two equivalent Rh, and three B atoms. There are a spread of Ti–Ru bond distances ranging from 2.73–2.90 Å. Both Ti–Rh bond lengths are 2.95 Å. There are a spread of Ti–B bond distances ranging from 2.56–2.88 Å. In the second Ti site, Ti is bonded in a 7-coordinate geometry to eight Ru, two equivalent Rh, and three B atoms. There are a spread of Ti–Ru bond distances ranging from 2.70–2.92 Å. Both Ti–Rh bond lengths are 2.81 Å. There are one shorter (2.64 Å) and two longer (2.78 Å) Ti–B bond lengths. There are five inequivalent Ru sites. In the first Ru site, Ru is bonded in a 8-coordinate geometry to four Ti, two equivalent Fe, and two equivalent B atoms. Both Ru–Fe bond lengths are 2.53 Å. Both Ru–B bond lengths are 2.15 Å. In the second Ru site, Ru is bonded in a 8-coordinate geometry to four Ti, two equivalent Fe, and two equivalent B atoms. Both Ru–Fe bond lengths are 2.53 Å. Both Ru–B bond lengths are 2.17 Å. In the third Ru site, Ru is bonded in a 8-coordinate geometry to four Ti, two equivalent Fe, and two equivalent B atoms. Both Ru–Fe bond lengths are 2.55 Å. Both Ru–B bond lengths are 2.14 Å. In the fourth Ru site, Ru is bonded in a 8-coordinate geometry to four equivalent Ti and four equivalent B atoms. All Ru–B bond lengths are 2.19 Å. In the fifth Ru site, Ru is bonded in a distorted body-centered cubic geometry to four equivalent Ti and four equivalent B atoms. All Ru–B bond lengths are 2.19 Å. There are two inequivalent Fe sites. In the first Fe site, Fe is bonded in a body-centered cubic geometry to four equivalent Ru and four equivalent Rh atoms. All Fe–Rh bond lengths are 2.53 Å. In the second Fe site, Fe is bonded in a body-centered cubic geometry to eight Ru atoms. Rh is bonded in a 4-coordinate geometry to four Ti, two equivalent Fe, and two equivalent B atoms. Both Rh–B bond lengths are 2.16 Å. There are two inequivalent B sites. In the first B site, B is bonded in a 9-coordinate geometry to three Ti and six Ru atoms. In the second B site, B is bonded in a 6-coordinate geometry to three Ti, four Ru, and two equivalent Rh atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on ScGeRh by Materials Project

ScRhGe crystallizes in the hexagonal P-62m space group. The structure is three-dimensional. Sc is bonded in a 11-coordinate geometry to six equivalent Rh and five Ge atoms. There are two shorter (2.97 Å) and four longer (3.11 Å) Sc–Rh bond lengths. There are four shorter (2.79 Å) and one longer (2.81 Å) Sc–Ge bond lengths. Rh is bonded in a 12-coordinate geometry to six equivalent Sc, two equivalent Rh, and four Ge atoms. Both Rh–Rh bond lengths are 2.86 Å. There are two shorter (2.53 Å) and two longer (2.59 Å) Rh–Ge bond lengths. There are two inequivalent Ge sites. In the first Ge site, Ge is bonded in a 9-coordinate geometry to six equivalent Sc and three equivalent Rh atoms. In the second Ge site, Ge is bonded in a 9-coordinate geometry to three equivalent Sc and six equivalent Rh atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Economizing on Precious Metals in Three‐Way Catalysts: Thermally Stable and Highly Active Single‐Atom Rhodium on Ceria for NO Abatement under Dry and Industrially Relevant Conditions**

Abstract We show for the first time that atomically dispersed Rh cations on ceria, prepared by a high‐temperature atom‐trapping synthesis, are the active species for the (CO+NO) reaction. This provides a direct link with the organometallic homogeneous Rh I complexes capable of catalyzing the dry (CO+NO) reaction. The thermally stable Rh cations in 0.1 wt % Rh 1 /CeO 2 achieve full NO conversion with a turn‐over‐frequency (TOF) of around 330 h −1 per Rh atom at 120 °C. Under dry conditions, the main product above 100 °C is N 2 with N 2 O being the minor product. The presence of water promotes low‐temperature activity of 0.1 wt % Rh 1 /CeO 2 . In the wet stream, ammonia and nitrogen are the main products above 120 °C. The uniformity of Rh ions on the support, allows us to detect the intermediates of (CO+NO) reaction via IR measurements on Rh cations on zeolite and ceria. We also show that NH 3 formation correlates with the water gas shift (WGS) activity of the material and detect the formation of Rh hydride species spectroscopically.

Khivantsev, Konstantin↗
DOE OSTI2021

Long-Term Effects of Humidity on Stainless Steel Pitting in Sea Salt Exposures

Ground 304 stainless steel (SS) samples were exposed to sea salt particles at 35 °C and two relative humidity (RH) levels for durations ranging from 1 week to 2 years. For all exposure times, pit number density and total pit volume at 40% RH were observed to be considerably greater than those at 76% RH. Statistical analysis of distributions of pit populations for both RH conditions showed that pit number density and total pit volume increased rapidly at first but slowed as exposure time increased. Cross-hatched features were observed in the 40% RH pits while ellipsoidal, faceted pits were observed at 76% RH. Optical profilometry indicated that most pits were not hemispherical. X-ray tomography provided evidence of undercutting and fissures. Piecewise curve fitting modeled the 40% RH data closely, predicting that corrosion damage would eventually plateau. However, a similar treatment of the 76% RH data suggested that corrosion damage would continuously increase, which implied that the piecewise power-law fit was limited in its ability to model atmospheric corrosion generally. Based on these observations, the operative mechanisms determining long-term corrosion behavior were hypothesized to be different depending on the RH of exposure.

36 MATERIALS SCIENCE↗