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All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Materials Data on Cu(PO3)2 by Materials Project

Cu(PO3)2 crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. there are two inequivalent Cu2+ sites. In the first Cu2+ site, Cu2+ is bonded to six O2- atoms to form distorted CuO6 octahedra that share corners with six PO4 tetrahedra and edges with two equivalent CuO6 octahedra. There are a spread of Cu–O bond distances ranging from 1.93–2.69 Å. In the second Cu2+ site, Cu2+ is bonded to six O2- atoms to form CuO6 octahedra that share corners with six PO4 tetrahedra and edges with two equivalent CuO6 octahedra. There are a spread of Cu–O bond distances ranging from 1.96–2.52 Å. There are two inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with three CuO6 octahedra and corners with two equivalent PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 31–60°. There are a spread of P–O bond distances ranging from 1.49–1.61 Å. In the second P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with three CuO6 octahedra and corners with two equivalent PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 26–53°. There are a spread of P–O bond distances ranging from 1.49–1.62 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 150 degrees geometry to one Cu2+ and one P5+ atom. In the second O2- site, O2- is bonded in a 2-coordinate geometry to two Cu2+ and one P5+ atom. In the third O2- site, O2- is bonded in a 3-coordinate geometry to two Cu2+ and one P5+ atom. In the fourth O2- site, O2- is bonded in a bent 150 degrees geometry to two P5+ atoms. In the fifth O2- site, O2- is bonded in a bent 150 degrees geometry to one Cu2+ and one P5+ atom. In the sixth O2- site, O2- is bonded in a bent 150 degrees geometry to two P5+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Cu(HO)2 by Materials Project

Cu(OH)2 crystallizes in the orthorhombic Cmc2_1 space group. The structure is two-dimensional and consists of two Cu(OH)2 sheets oriented in the (0, 1, 0) direction. Cu2+ is bonded to five O2- atoms to form a mixture of edge and corner-sharing CuO5 square pyramids. There are a spread of Cu–O bond distances ranging from 1.97–2.30 Å. There are two inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the second H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted single-bond geometry to two equivalent Cu2+ and one H1+ atom. In the second O2- site, O2- is bonded in a distorted single-bond geometry to three equivalent Cu2+ and one H1+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Cu(CO)4 by Materials Project

Cu(CO)4 crystallizes in the monoclinic C2/c space group. The structure is one-dimensional and consists of two Cu(CO)4 ribbons oriented in the (0, 0, 1) direction. Cu2+ is bonded to six O2- atoms to form edge-sharing CuO6 octahedra. There are a spread of Cu–O bond distances ranging from 1.98–2.50 Å. There are two inequivalent C+1.50+ sites. In the first C+1.50+ site, C+1.50+ is bonded in a single-bond geometry to one O2- atom. The C–O bond length is 1.26 Å. In the second C+1.50+ site, C+1.50+ is bonded in a single-bond geometry to one O2- atom. The C–O bond length is 1.26 Å. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Cu2+ and one C+1.50+ atom. In the second O2- site, O2- is bonded in a bent 120 degrees geometry to one Cu2+ and one C+1.50+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Cu(IO3)2 by Materials Project

Cu(IO3)2 crystallizes in the monoclinic P2_1/m space group. The structure is two-dimensional and consists of one Cu(IO3)2 sheet oriented in the (0, 0, 1) direction. Cu2+ is bonded to six O2- atoms to form CuO6 octahedra that share corners with four equivalent IO5 square pyramids and edges with two equivalent CuO6 octahedra. There are a spread of Cu–O bond distances ranging from 1.97–2.41 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to one Cu2+ and one I5+ atom. The O–I bond length is 1.88 Å. In the second O2- site, O2- is bonded in a trigonal non-coplanar geometry to two equivalent Cu2+ and one I5+ atom. The O–I bond length is 1.93 Å. In the third O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Cu2+ and one I5+ atom. The O–I bond length is 1.80 Å. In the fourth O2- site, O2- is bonded in a distorted single-bond geometry to two I5+ atoms. There are one shorter (1.83 Å) and one longer (2.60 Å) O–I bond lengths. There are two inequivalent I5+ sites. In the first I5+ site, I5+ is bonded in a 5-coordinate geometry to three O2- atoms. In the second I5+ site, I5+ is bonded to five O2- atoms to form distorted IO5 square pyramids that share corners with four equivalent CuO6 octahedra. The corner-sharing octahedra tilt angles range from 45–49°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Cu(HO)2 by Materials Project

Cu(OH)2 crystallizes in the monoclinic P2_1 space group. The structure is two-dimensional and consists of one Cu(OH)2 sheet oriented in the (0, 0, 1) direction. Cu2+ is bonded to five O2- atoms to form a mixture of edge and corner-sharing CuO5 square pyramids. There are a spread of Cu–O bond distances ranging from 1.98–2.35 Å. There are two inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the second H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted single-bond geometry to two equivalent Cu2+ and one H1+ atom. In the second O2- site, O2- is bonded in a distorted single-bond geometry to three equivalent Cu2+ and one H1+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Cu(HO)2 by Materials Project

Cu(OH)2 crystallizes in the monoclinic Cc space group. The structure is two-dimensional and consists of two Cu(OH)2 sheets oriented in the (0, 1, 0) direction. Cu2+ is bonded to five O2- atoms to form a mixture of edge and corner-sharing CuO5 square pyramids. There are a spread of Cu–O bond distances ranging from 1.95–2.26 Å. There are two inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the second H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted single-bond geometry to two equivalent Cu2+ and one H1+ atom. In the second O2- site, O2- is bonded in a distorted single-bond geometry to three equivalent Cu2+ and one H1+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Cu(NO3)2 by Materials Project

Cu(NO3)2 crystallizes in the orthorhombic Pbcn space group. The structure is three-dimensional. there are two inequivalent Cu2+ sites. In the first Cu2+ site, Cu2+ is bonded in a 4-coordinate geometry to seven O2- atoms. There are a spread of Cu–O bond distances ranging from 1.97–2.70 Å. In the second Cu2+ site, Cu2+ is bonded in a square co-planar geometry to four O2- atoms. There are two shorter (1.99 Å) and two longer (2.02 Å) Cu–O bond lengths. There are three inequivalent N5+ sites. In the first N5+ site, N5+ is bonded in a trigonal planar geometry to three O2- atoms. There are a spread of N–O bond distances ranging from 1.22–1.31 Å. In the second N5+ site, N5+ is bonded in a trigonal planar geometry to three O2- atoms. There are a spread of N–O bond distances ranging from 1.22–1.32 Å. In the third N5+ site, N5+ is bonded in a trigonal planar geometry to three O2- atoms. There are a spread of N–O bond distances ranging from 1.23–1.29 Å. There are nine inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one N5+ atom. In the second O2- site, O2- is bonded in a single-bond geometry to one N5+ atom. In the third O2- site, O2- is bonded in a water-like geometry to one Cu2+ and one N5+ atom. In the fourth O2- site, O2- is bonded in a water-like geometry to one Cu2+ and one N5+ atom. In the fifth O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Cu2+ and one N5+ atom. In the sixth O2- site, O2- is bonded in a distorted water-like geometry to two Cu2+ and one N5+ atom. In the seventh O2- site, O2- is bonded in a water-like geometry to one Cu2+ and one N5+ atom. In the eighth O2- site, O2- is bonded in a water-like geometry to one Cu2+ and one N5+ atom. In the ninth O2- site, O2- is bonded in a single-bond geometry to one Cu2+ and one N5+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Cu(Mo3S4)2 by Materials Project

Cu(Mo3S4)2 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are twelve inequivalent Mo+2.50+ sites. In the first Mo+2.50+ site, Mo+2.50+ is bonded to five S2- atoms to form MoS5 square pyramids that share corners with four MoS5 square pyramids, corners with two CuS4 trigonal pyramids, and edges with five MoS5 square pyramids. There are a spread of Mo–S bond distances ranging from 2.42–2.46 Å. In the second Mo+2.50+ site, Mo+2.50+ is bonded to five S2- atoms to form MoS5 square pyramids that share corners with four MoS5 square pyramids, corners with two equivalent CuS4 trigonal pyramids, and edges with five MoS5 square pyramids. There are a spread of Mo–S bond distances ranging from 2.41–2.52 Å. In the third Mo+2.50+ site, Mo+2.50+ is bonded to five S2- atoms to form MoS5 square pyramids that share corners with four MoS5 square pyramids, corners with three equivalent CuS4 trigonal pyramids, and edges with five MoS5 square pyramids. There are a spread of Mo–S bond distances ranging from 2.42–2.49 Å. In the fourth Mo+2.50+ site, Mo+2.50+ is bonded to five S2- atoms to form MoS5 square pyramids that share corners with four MoS5 square pyramids, corners with three CuS4 trigonal pyramids, and edges with five MoS5 square pyramids. There are a spread of Mo–S bond distances ranging from 2.41–2.51 Å. In the fifth Mo+2.50+ site, Mo+2.50+ is bonded to five S2- atoms to form MoS5 square pyramids that share corners with four MoS5 square pyramids, a cornercorner with one CuS4 trigonal pyramid, edges with five MoS5 square pyramids, and an edgeedge with one CuS4 trigonal pyramid. There are a spread of Mo–S bond distances ranging from 2.41–2.48 Å. In the sixth Mo+2.50+ site, Mo+2.50+ is bonded to five S2- atoms to form MoS5 square pyramids that share corners with four MoS5 square pyramids, corners with two CuS4 trigonal pyramids, and edges with five MoS5 square pyramids. There are a spread of Mo–S bond distances ranging from 2.43–2.47 Å. In the seventh Mo+2.50+ site, Mo+2.50+ is bonded to five S2- atoms to form MoS5 square pyramids that share corners with four MoS5 square pyramids, a cornercorner with one CuS4 trigonal pyramid, edges with five MoS5 square pyramids, and an edgeedge with one CuS4 trigonal pyramid. There are a spread of Mo–S bond distances ranging from 2.41–2.49 Å. In the eighth Mo+2.50+ site, Mo+2.50+ is bonded to five S2- atoms to form MoS5 square pyramids that share corners with four MoS5 square pyramids, corners with two equivalent CuS4 trigonal pyramids, and edges with five MoS5 square pyramids. There are a spread of Mo–S bond distances ranging from 2.41–2.50 Å. In the ninth Mo+2.50+ site, Mo+2.50+ is bonded to five S2- atoms to form MoS5 square pyramids that share corners with four MoS5 square pyramids, a cornercorner with one CuS4 trigonal pyramid, and edges with five MoS5 square pyramids. There are a spread of Mo–S bond distances ranging from 2.41–2.47 Å. In the tenth Mo+2.50+ site, Mo+2.50+ is bonded to five S2- atoms to form MoS5 square pyramids that share corners with four MoS5 square pyramids, corners with two equivalent CuS4 trigonal pyramids, and edges with five MoS5 square pyramids. There are a spread of Mo–S bond distances ranging from 2.41–2.46 Å. In the eleventh Mo+2.50+ site, Mo+2.50+ is bonded to five S2- atoms to form MoS5 square pyramids that share corners with four MoS5 square pyramids, corners with three CuS4 trigonal pyramids, and edges with five MoS5 square pyramids. There are a spread of Mo–S bond distances ranging from 2.43–2.47 Å. In the twelfth Mo+2.50+ site, Mo+2.50+ is bonded to five S2- atoms to form MoS5 square pyramids that share corners with four MoS5 square pyramids, corners with two CuS4 trigonal pyramids, and edges with five MoS5 square pyramids. There are a spread of Mo–S bond distances ranging from 2.41–2.49 Å. There are two inequivalent Cu1+ sites. In the first Cu1+ site, Cu1+ is bonded to four S2- atoms to form distorted CuS4 trigonal pyramids that share corners with twelve MoS5 square pyramids and an edgeedge with one MoS5 square pyramid. There are a spread of Cu–S bond distances ranging from 2.28–2.56 Å. In the second Cu1+ site, Cu1+ is bonded to four S2- atoms to form distorted CuS4 trigonal pyramids that share corners with twelve MoS5 square pyramids and an edgeedge with one MoS5 square pyramid. There are a spread of Cu–S bond distances ranging from 2.28–2.55 Å. There are sixteen inequivalent S2- sites. In the first S2- site, S2- is bonded in a 4-coordinate geometry to four Mo+2.50+ atoms. In the second S2- site, S2- is bonded in a 5-coordinate geometry to four Mo+2.50+ and one Cu1+ atom. In the third S2- site, S2- is bonded in a 5-coordinate geometry to four Mo+2.50+ and one Cu1+ atom. In the fourth S2- site, S2- is bonded in a 1-coordinate geometry to three Mo+2.50+ and one Cu1+ atom. In the fifth S2- site, S2- is bonded in a 4-coordinate geometry to four Mo+2.50+ atoms. In the sixth S2- site, S2- is bonded in a 1-coordinate geometry to three Mo+2.50+ and one Cu1+ atom. In the seventh S2- site, S2- is bonded in a 4-coordinate geometry to four Mo+2.50+ atoms. In the eighth S2- site, S2- is bonded in a 4-coordinate geometry to four Mo+2.50+ atoms. In the ninth S2- site, S2- is bonded in a 5-coordinate geometry to four Mo+2.50+ and one Cu1+ atom. In the tenth S2- site, S2- is bonded in a 4-coordinate geometry to four Mo+2.50+ atoms. In the eleventh S2- site, S2- is bonded in a 1-coordinate geometry to three Mo+2.50+ and one Cu1+ atom. In the twelfth S2- site, S2- is bonded in a 5-coordinate geometry to four Mo+2.50+ and one Cu1+ atom. In the thirteenth S2- site, S2- is bonded in a 1-coordinate geometry to three Mo+2.50+ and one Cu1+ atom. In the fourteenth S2- site, S2- is bonded in a 4-coordinate geometry to four Mo+2.50+ atoms. In the fifteenth S2- site, S2- is bonded in a 4-coordinate geometry to four Mo+2.50+ atoms. In the sixteenth S2- site, S2- is bonded in a 4-coordinate geometry to four Mo+2.50+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Cu(PO3)3 by Materials Project

Cu(PO3)3 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are two inequivalent Cu3+ sites. In the first Cu3+ site, Cu3+ is bonded to five O2- atoms to form distorted CuO5 square pyramids that share corners with five PO4 tetrahedra. There are a spread of Cu–O bond distances ranging from 1.92–2.24 Å. In the second Cu3+ site, Cu3+ is bonded to five O2- atoms to form CuO5 trigonal bipyramids that share corners with five PO4 tetrahedra. There are a spread of Cu–O bond distances ranging from 1.89–2.22 Å. There are six inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two PO4 tetrahedra and corners with two equivalent CuO5 trigonal bipyramids. There are a spread of P–O bond distances ranging from 1.48–1.62 Å. In the second P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two equivalent CuO5 square pyramids and corners with two PO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.50–1.60 Å. In the third P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two equivalent CuO5 square pyramids and corners with two PO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.51–1.59 Å. In the fourth P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two PO4 tetrahedra and a cornercorner with one CuO5 trigonal bipyramid. There are a spread of P–O bond distances ranging from 1.47–1.63 Å. In the fifth P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two PO4 tetrahedra and a cornercorner with one CuO5 trigonal bipyramid. There are a spread of P–O bond distances ranging from 1.48–1.63 Å. In the sixth P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share a cornercorner with one CuO5 square pyramid, corners with two PO4 tetrahedra, and a cornercorner with one CuO5 trigonal bipyramid. There are a spread of P–O bond distances ranging from 1.48–1.62 Å. There are eighteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Cu3+ and one P5+ atom. In the second O2- site, O2- is bonded in a bent 150 degrees geometry to two P5+ atoms. In the third O2- site, O2- is bonded in a bent 120 degrees geometry to two P5+ atoms. In the fourth O2- site, O2- is bonded in a bent 120 degrees geometry to two P5+ atoms. In the fifth O2- site, O2- is bonded in a bent 150 degrees geometry to one Cu3+ and one P5+ atom. In the sixth O2- site, O2- is bonded in a bent 150 degrees geometry to two P5+ atoms. In the seventh O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Cu3+ and one P5+ atom. In the eighth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Cu3+ and one P5+ atom. In the ninth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two P5+ atoms. In the tenth O2- site, O2- is bonded in a bent 150 degrees geometry to two P5+ atoms. In the eleventh O2- site, O2- is bonded in a single-bond geometry to one P5+ atom. In the twelfth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Cu3+ and one P5+ atom. In the thirteenth O2- site, O2- is bonded in a bent 150 degrees geometry to one Cu3+ and one P5+ atom. In the fourteenth O2- site, O2- is bonded in a bent 120 degrees geometry to one Cu3+ and one P5+ atom. In the fifteenth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Cu3+ and one P5+ atom. In the sixteenth O2- site, O2- is bonded in a single-bond geometry to one P5+ atom. In the seventeenth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Cu3+ and one P5+ atom. In the eighteenth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Cu3+ and one P5+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Cu(CO2)4 by Materials Project

Cu(C2O4)2 crystallizes in the monoclinic P2_1/c space group. The structure is two-dimensional and consists of one Cu(C2O4)2 sheet oriented in the (1, 0, 0) direction. Cu2+ is bonded in an octahedral geometry to six O2- atoms. There are a spread of Cu–O bond distances ranging from 2.07–2.54 Å. There are two inequivalent C+3.50+ sites. In the first C+3.50+ site, C+3.50+ is bonded in a bent 150 degrees geometry to two O2- atoms. Both C–O bond lengths are 1.22 Å. In the second C+3.50+ site, C+3.50+ is bonded in a linear geometry to two O2- atoms. Both C–O bond lengths are 1.18 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Cu2+ and one C+3.50+ atom. In the second O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Cu2+ and one C+3.50+ atom. In the third O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Cu2+ and one C+3.50+ atom. In the fourth O2- site, O2- is bonded in a single-bond geometry to one C+3.50+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Cu(CO4)2 by Materials Project

CuO2(CO2)2O2 is Cyanogen Chloride-like structured and crystallizes in the monoclinic P2_1/c space group. The structure is one-dimensional and consists of four carbon dioxide molecules; two hydrogen peroxide molecules; and two CuO2 ribbons oriented in the (1, 0, 0) direction. In each CuO2 ribbon, Cu is bonded in a linear geometry to two equivalent O atoms. Both Cu–O bond lengths are 1.82 Å. O is bonded in a distorted bent 120 degrees geometry to one Cu and one O atom. The O–O bond length is 1.39 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Cu(N2O3)2 by Materials Project

Cu(N2O3)2 is Protactinium structured and crystallizes in the orthorhombic Pbca space group. The structure is zero-dimensional and consists of four copper, diamminebis(nitrato-kappao)- molecules. Cu2+ is bonded in a distorted linear geometry to two equivalent N+2.50+ and two equivalent O2- atoms. Both Cu–N bond lengths are 1.93 Å. Both Cu–O bond lengths are 1.89 Å. There are two inequivalent N+2.50+ sites. In the first N+2.50+ site, N+2.50+ is bonded in a distorted single-bond geometry to one Cu2+ atom. In the second N+2.50+ site, N+2.50+ is bonded in a trigonal planar geometry to three O2- atoms. There are a spread of N–O bond distances ranging from 1.23–1.35 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one N+2.50+ atom. In the second O2- site, O2- is bonded in a bent 120 degrees geometry to one Cu2+ and one N+2.50+ atom. In the third O2- site, O2- is bonded in a single-bond geometry to one N+2.50+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Cu(CO4)2 by Materials Project

CuO2(CO2)2O2 is Cyanogen Chloride-like structured and crystallizes in the monoclinic P2_1/c space group. The structure is one-dimensional and consists of four carbon dioxide molecules; two hydrogen peroxide molecules; and two CuO2 ribbons oriented in the (1, 0, 0) direction. In each CuO2 ribbon, Cu is bonded in a linear geometry to two equivalent O atoms. Both Cu–O bond lengths are 1.81 Å. O is bonded in a distorted bent 120 degrees geometry to one Cu and one O atom. The O–O bond length is 1.39 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2022

Grain Boundary‐Derived Cu + /Cu 0 Interfaces in CuO Nanosheets for Low Overpotential Carbon Dioxide Electroreduction to Ethylene

Abstract Electrochemical CO 2 reduction reaction can be used to produce value‐added hydrocarbon fuels and chemicals by coupling with clean electrical energy. However, highly active, selective, and energy‐efficient CO 2 conversion to multicarbon hydrocarbons, such as C 2 H 4 , remains challenging because of the lack of efficient catalysts. Herein, an ultrasonication‐assisted electrodeposition strategy to synthesize CuO nanosheets for low‐overpotential CO 2 electroreduction to C 2 H 4 is reported. A high C 2 H 4 Faradaic efficiency of 62.5% is achieved over the CuO nanosheets at a small potential of −0.52 V versus a reversible hydrogen electrode, corresponding to a record high half‐cell cathodic energy efficiency of 41%. The selectivity toward C 2 H 4 is maintained for over 60 h of continuous operation. The CuO nanosheets are prone to in situ restructuring during CO 2 reduction, forming abundant grain boundaries (GBs). Stable Cu + /Cu 0 interfaces are derived from the low‐coordinated Cu atoms in the reconstructed GB regions and act as highly active sites for CO 2 reduction at low overpotentials. In situ Raman spectroscopic analysis and density functional theory computation reveal that the Cu + /Cu 0 interfaces offer high *CO surface coverage and lower the activation energy barrier for *CO dimerization, which, in synergy, facilitates CO 2 reduction to C 2 H 4 at low overpotentials.

36 MATERIALS SCIENCE↗
DOE OSTI2024

Theoretical Investigation of the Adsorbate and Potential–Induced Stability of Cu Facets During Electrochemical CO 2 and CO Reduction

The activity and product selectivity of electrocatalysts for reactions like the carbon dioxide reduction reaction (CO 2 RR) are intimately dependent on the catalyst's structure and composition. While engineering catalytic surfaces can improve performance, discovering the key sets of rational design principles remains challenging due to limitations in modeling catalyst stability under operating conditions. Herein, we perform first-principles density functional calculations adopting implicit solvation methods with potential control to study the influence of adsorbates and applied potential on the stability of different facets of model Cu electrocatalysts. Using coverage dependencies extracted from microkinetic models, we describe an approach for calculating potential and adsorbate-dependent contributions to surface energies under reaction conditions, where Wulff constructions are used to understand the morphological evolution of Cu electrocatalysts under CO 2 RR conditions. Here we identify that CO*, a key reaction intermediate, exhibits higher kinetically and thermodynamically accessible coverages on (100) relative to (111) facets, which can translate into an increased relative stabilization of the (100) facet during CO 2 RR. Our results support the known tendency for increased (111) faceting of Cu nanoparticles under more reducing conditions and that the relative increase in (100) faceting observed under CO 2 RR conditions is likely attributed to differences in CO* coverage between these facets.

30 DIRECT ENERGY CONVERSION↗
DOE OSTI2022

Cavitation-resistant intergranular precipitates enhance creep performance of θ'-strengthened Al-Cu based alloys

Tensile and compressive creep properties of a quaternary Al-Cu-Mn-Zr (ACMZ) alloy and its commercial counterpart (Al-Cu-Mn-Zr with Ni, Co and Sb additions, RR350) are investigated at 300°C. At low stresses up to 30 MPa where diffusional creep dominates, creep resistance is the same in tension and compression and RR350 deforms more slowly than ACMZ, consistent with RR350 alloy's larger linear fraction of intergranular precipitates (Al7Cu2(NiFe) and Al9FeNi for RR350 vs. θ-Al2Cu for ACMZ) and a reduced fraction of precipitate-free zones near grain boundaries. At stresses between 30 and 80 MPa, dislocation creep with a stress exponent n ~ 3 becomes rate-limiting in compression, which is expected to be controlled by θ' precipitates within the grain bulk. By contrast, in tension, enhanced creep rate and higher apparent stress exponents are measured, consistent with cavitation at intergranular precipitates becoming increasingly dominant as the stress increases. In the dislocation creep regime, RR350 alloy is again more creep resistant than ACMZ alloy, which is related to three mechanisms (i) a reduced fraction of softer precipitate-free zones, (ii) more effective load transfer to intergranular precipitates, and (iii) reduced cavitation. A model for cavitation is applied to calculate tensile creep rates from compressive creep rates and the model successfully predicts the improved tensile creep resistance of the RR350 alloy. Overall, the present investigation underscores the importance of intergranular grain boundary precipitates, in addition to strengthening θ' precipitates, in enhancing the creep resistance of Al-Cu alloys.

36 MATERIALS SCIENCE↗
DOE OSTI2023

Progression of creep deformation from grain boundaries to grain interior in Al-Cu-Mn-Zr alloys

Creep mechanisms are studied in θ'-Al 2 Cu-strengthened Al-Cu-Mn-Zr alloys at 300 and 350°C for (i) ACMZ, a base alloy without further alloying elements and (ii) RR350, a commercial alloy with additions of Ni and Co forming distinct grain-boundary precipitates. At high stresses, creep is dominated by dislocations bypassing θ' precipitates within grains via the Orowan mechanism, as evidenced by (i) very high stress exponent (n~20-25) and (ii) α-Al and θ' lattice strains (measured via in-situ neutron diffraction) evolving during creep in a manner consistent with load transfer from the plastically-deforming α-Al matrix to elastically-deforming θ' precipitates. At intermediate stresses, both alloys exhibit a n~3 regime, where α-Al and θ' lattice strains scale near-linearly with applied stress while remaining largely unaffected by strain accumulation, indicating that Orowan looping or dislocation pile-up around θ' is now inactive within the grains. Rather, dislocation motion occurs solely in θ'-precipitate-free zones (θ'-PFZ) where high dislocation densities are observed via TEM after creep deformation. Plastic flow at θ'-PFZ and/or localized pipe diffusion are expected to enable grain-boundary sliding (GBS), which is proposed as the rate-limiting mechanism in the n~3 regime. Ni/Co-rich precipitates at RR350 grain-boundaries, with negligible θ'-PFZ around them, share load (as determined via neutron diffraction) with the α-Al matrix more effectively than θ-Al 2 Cu precipitates at ACMZ grain-boundaries, with wide surrounding θ'-PFZ. So, high creep resistance in the n~3 GBS regime of RR350 is enabled by coarsening-resistant grain-boundary precipitates, forming without concomitant development of weak θ'-PFZ, which effectively share load with the grains.

36 MATERIALS SCIENCE↗
DOE OSTI2022

On the various Cu-redox pathways and O 2 -mediated Bronsted-to-Lewis adsorbed-NH 3 redistribution under SCR half-cycle conditions

The Standard SCR reaction on Cu-SSZ-13 is a complex redox process facilitated by a reduction half cycle (RHC) and an oxidation half cycle (OHC). It is generally accepted that RHC requires the simultaneous presence of NO and NH 3 , while OHC requires both NO and O 2 ; however understanding of how these individual reactants impact the Cu redox cycle is limited. In this work, we provide experimental investigation of NO-only, NH 3 -only and NO+NH 3 RHC, and their relative rates. Simple kinetic models were developed to understand the dependance of NO-only and NH 3 -only RHC on Cu speciation. Various OHC routes including NO+O 2 and O 2 -only OHC, and a previously unreported H 2 O-mediated OHC pathway were also investigated. Detailed NH 3 temperature-programmed desorption studies showed that RHC selectively consumes NH 3 adsorbed on Lewis-acid sites, and that part of the remaining Bronsted-bound NH 3 moves to the Lewis-acid sites during subsequent OHC, thereby resulting in a repartitioning of adsorbed NH 3 .

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗