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At least 1,747 records · Page 97
All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Materials Data on CrIr3 by Materials Project

Ir3Cr is Uranium Silicide-like structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. Cr is bonded to twelve equivalent Ir atoms to form CrIr12 cuboctahedra that share corners with six equivalent CrIr12 cuboctahedra, corners with twelve equivalent IrCr4Ir8 cuboctahedra, edges with eighteen equivalent IrCr4Ir8 cuboctahedra, faces with eight equivalent CrIr12 cuboctahedra, and faces with twelve equivalent IrCr4Ir8 cuboctahedra. There are six shorter (2.66 Å) and six longer (2.72 Å) Cr–Ir bond lengths. Ir is bonded to four equivalent Cr and eight equivalent Ir atoms to form distorted IrCr4Ir8 cuboctahedra that share corners with four equivalent CrIr12 cuboctahedra, corners with fourteen equivalent IrCr4Ir8 cuboctahedra, edges with six equivalent CrIr12 cuboctahedra, edges with twelve equivalent IrCr4Ir8 cuboctahedra, faces with four equivalent CrIr12 cuboctahedra, and faces with sixteen equivalent IrCr4Ir8 cuboctahedra. There are six shorter (2.68 Å) and two longer (2.76 Å) Ir–Ir bond lengths.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on TbSi3Ir by Materials Project

TbIrSi3 crystallizes in the tetragonal I4mm space group. The structure is three-dimensional. Tb is bonded in a 8-coordinate geometry to five equivalent Ir and twelve Si atoms. There are four shorter (3.33 Å) and one longer (3.39 Å) Tb–Ir bond lengths. There are a spread of Tb–Si bond distances ranging from 3.08–3.35 Å. Ir is bonded in a 5-coordinate geometry to five equivalent Tb and five Si atoms. There are one shorter (2.33 Å) and four longer (2.37 Å) Ir–Si bond lengths. There are two inequivalent Si sites. In the first Si site, Si is bonded in a distorted single-bond geometry to four equivalent Tb, one Ir, and four equivalent Si atoms. All Si–Si bond lengths are 2.56 Å. In the second Si site, Si is bonded in a distorted bent 120 degrees geometry to four equivalent Tb, two equivalent Ir, and two equivalent Si atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on CeSi3Ir by Materials Project

CeIrSi3 crystallizes in the tetragonal I4mm space group. The structure is three-dimensional. Ce is bonded in a 8-coordinate geometry to five equivalent Ir and twelve Si atoms. There are one shorter (3.35 Å) and four longer (3.37 Å) Ce–Ir bond lengths. There are eight shorter (3.10 Å) and four longer (3.39 Å) Ce–Si bond lengths. Ir is bonded in a 5-coordinate geometry to five equivalent Ce and five Si atoms. There are one shorter (2.37 Å) and four longer (2.38 Å) Ir–Si bond lengths. There are two inequivalent Si sites. In the first Si site, Si is bonded in a distorted single-bond geometry to four equivalent Ce, one Ir, and four equivalent Si atoms. All Si–Si bond lengths are 2.57 Å. In the second Si site, Si is bonded in a distorted bent 120 degrees geometry to four equivalent Ce, two equivalent Ir, and two equivalent Si atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Mo4Ir by Materials Project

Mo4Ir is alpha La-derived structured and crystallizes in the trigonal R-3m space group. The structure is three-dimensional. there are five inequivalent Mo sites. In the first Mo site, Mo is bonded to nine Mo and three equivalent Ir atoms to form MoMo9Ir3 cuboctahedra that share corners with twelve MoMo9Ir3 cuboctahedra, edges with six equivalent IrMo6Ir6 cuboctahedra, edges with eighteen MoMo9Ir3 cuboctahedra, faces with six equivalent IrMo6Ir6 cuboctahedra, and faces with twelve MoMo9Ir3 cuboctahedra. There are six shorter (2.78 Å) and three longer (2.92 Å) Mo–Mo bond lengths. All Mo–Ir bond lengths are 2.78 Å. In the second Mo site, Mo is bonded to twelve Mo atoms to form MoMo12 cuboctahedra that share corners with three equivalent IrMo6Ir6 cuboctahedra, corners with nine MoMo9Ir3 cuboctahedra, edges with three equivalent IrMo6Ir6 cuboctahedra, edges with twenty-one MoMo9Ir3 cuboctahedra, and faces with eighteen MoMo9Ir3 cuboctahedra. There are six shorter (2.78 Å) and three longer (2.90 Å) Mo–Mo bond lengths. In the third Mo site, Mo is bonded to twelve Mo atoms to form MoMo12 cuboctahedra that share corners with three equivalent IrMo6Ir6 cuboctahedra, corners with nine MoMo9Ir3 cuboctahedra, edges with three equivalent IrMo6Ir6 cuboctahedra, edges with twenty-one MoMo9Ir3 cuboctahedra, and faces with eighteen MoMo9Ir3 cuboctahedra. There are six shorter (2.78 Å) and three longer (2.92 Å) Mo–Mo bond lengths. In the fourth Mo site, Mo is bonded to twelve Mo atoms to form MoMo12 cuboctahedra that share corners with three equivalent IrMo6Ir6 cuboctahedra, corners with nine MoMo9Ir3 cuboctahedra, edges with three equivalent IrMo6Ir6 cuboctahedra, edges with twenty-one MoMo9Ir3 cuboctahedra, and faces with eighteen MoMo9Ir3 cuboctahedra. There are a spread of Mo–Mo bond distances ranging from 2.78–2.92 Å. In the fifth Mo site, Mo is bonded to twelve Mo atoms to form MoMo12 cuboctahedra that share corners with three equivalent IrMo6Ir6 cuboctahedra, corners with nine MoMo9Ir3 cuboctahedra, edges with three equivalent IrMo6Ir6 cuboctahedra, edges with twenty-one MoMo9Ir3 cuboctahedra, and faces with eighteen MoMo9Ir3 cuboctahedra. There are six shorter (2.78 Å) and three longer (2.92 Å) Mo–Mo bond lengths. Ir is bonded to six equivalent Mo and six equivalent Ir atoms to form IrMo6Ir6 cuboctahedra that share corners with six equivalent MoMo12 cuboctahedra, corners with six equivalent IrMo6Ir6 cuboctahedra, edges with six equivalent IrMo6Ir6 cuboctahedra, edges with eighteen MoMo9Ir3 cuboctahedra, faces with six equivalent IrMo6Ir6 cuboctahedra, and faces with twelve equivalent MoMo9Ir3 cuboctahedra. All Ir–Ir bond lengths are 2.78 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on ErB4(IrRh)2 by Materials Project

ErB4(IrRh)2 crystallizes in the tetragonal P4_2mc space group. The structure is three-dimensional. Er is bonded in a 12-coordinate geometry to six equivalent Ir, six equivalent Rh, and twelve B atoms. There are two shorter (2.98 Å) and four longer (3.19 Å) Er–Ir bond lengths. There are two shorter (2.96 Å) and four longer (3.20 Å) Er–Rh bond lengths. There are a spread of Er–B bond distances ranging from 3.05–3.16 Å. Ir is bonded in a 5-coordinate geometry to three equivalent Er and five B atoms. There are four shorter (2.22 Å) and one longer (2.27 Å) Ir–B bond lengths. Rh is bonded in a 5-coordinate geometry to three equivalent Er and five B atoms. There are a spread of Rh–B bond distances ranging from 2.22–2.24 Å. There are two inequivalent B sites. In the first B site, B is bonded in a 6-coordinate geometry to three equivalent Er, three equivalent Ir, two equivalent Rh, and one B atom. The B–B bond length is 1.84 Å. In the second B site, B is bonded in a 6-coordinate geometry to three equivalent Er, two equivalent Ir, three equivalent Rh, and one B atom. The B–B bond length is 1.83 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on NdSi3Ir by Materials Project

NdIrSi3 crystallizes in the tetragonal I4mm space group. The structure is three-dimensional. Nd is bonded in a 12-coordinate geometry to five equivalent Ir and twelve Si atoms. There are four shorter (3.38 Å) and one longer (3.40 Å) Nd–Ir bond lengths. There are a spread of Nd–Si bond distances ranging from 3.13–3.37 Å. Ir is bonded in a 5-coordinate geometry to five equivalent Nd and five Si atoms. There are one shorter (2.38 Å) and four longer (2.39 Å) Ir–Si bond lengths. There are two inequivalent Si sites. In the first Si site, Si is bonded in a distorted single-bond geometry to four equivalent Nd, one Ir, and four equivalent Si atoms. All Si–Si bond lengths are 2.60 Å. In the second Si site, Si is bonded in a distorted bent 120 degrees geometry to four equivalent Nd, two equivalent Ir, and two equivalent Si atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ir3Os by Materials Project

OsIr3 is Uranium Silicide structured and crystallizes in the cubic Pm-3m space group. The structure is three-dimensional. Os is bonded to twelve equivalent Ir atoms to form OsIr12 cuboctahedra that share corners with twelve equivalent OsIr12 cuboctahedra, edges with twenty-four equivalent IrIr8Os4 cuboctahedra, faces with six equivalent OsIr12 cuboctahedra, and faces with twelve equivalent IrIr8Os4 cuboctahedra. All Os–Ir bond lengths are 2.74 Å. Ir is bonded to four equivalent Os and eight equivalent Ir atoms to form IrIr8Os4 cuboctahedra that share corners with twelve equivalent IrIr8Os4 cuboctahedra, edges with eight equivalent OsIr12 cuboctahedra, edges with sixteen equivalent IrIr8Os4 cuboctahedra, faces with four equivalent OsIr12 cuboctahedra, and faces with fourteen equivalent IrIr8Os4 cuboctahedra. All Ir–Ir bond lengths are 2.74 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on La2Ge4IrPd3 by Materials Project

La2IrPd3Ge4 crystallizes in the tetragonal P4mm space group. The structure is three-dimensional. there are two inequivalent La sites. In the first La site, La is bonded in a 12-coordinate geometry to eight Pd and eight Ge atoms. There are four shorter (3.37 Å) and four longer (3.39 Å) La–Pd bond lengths. There are four shorter (3.31 Å) and four longer (3.40 Å) La–Ge bond lengths. In the second La site, La is bonded in a 12-coordinate geometry to four equivalent Ir, four equivalent Pd, and eight Ge atoms. All La–Ir bond lengths are 3.38 Å. All La–Pd bond lengths are 3.37 Å. There are four shorter (3.30 Å) and four longer (3.37 Å) La–Ge bond lengths. Ir is bonded in a 5-coordinate geometry to four equivalent La and five Ge atoms. There are one shorter (2.44 Å) and four longer (2.53 Å) Ir–Ge bond lengths. There are two inequivalent Pd sites. In the first Pd site, Pd is bonded in a 9-coordinate geometry to four equivalent La and five Ge atoms. There are one shorter (2.47 Å) and four longer (2.56 Å) Pd–Ge bond lengths. In the second Pd site, Pd is bonded in a 4-coordinate geometry to four La and four Ge atoms. There are two shorter (2.56 Å) and two longer (2.59 Å) Pd–Ge bond lengths. There are three inequivalent Ge sites. In the first Ge site, Ge is bonded in a 9-coordinate geometry to four equivalent La, one Ir, and four equivalent Pd atoms. In the second Ge site, Ge is bonded in a 9-coordinate geometry to four equivalent La and five Pd atoms. In the third Ge site, Ge is bonded in a 8-coordinate geometry to four La, two equivalent Ir, and two equivalent Pd atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on FeIr3 by Materials Project

FeIr3 is beta Cu3Ti-like structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. Fe is bonded to twelve equivalent Ir atoms to form FeIr12 cuboctahedra that share corners with six equivalent FeIr12 cuboctahedra, corners with twelve equivalent IrFe4Ir8 cuboctahedra, edges with eighteen equivalent IrFe4Ir8 cuboctahedra, faces with eight equivalent FeIr12 cuboctahedra, and faces with twelve equivalent IrFe4Ir8 cuboctahedra. There are six shorter (2.64 Å) and six longer (2.70 Å) Fe–Ir bond lengths. Ir is bonded to four equivalent Fe and eight equivalent Ir atoms to form distorted IrFe4Ir8 cuboctahedra that share corners with four equivalent FeIr12 cuboctahedra, corners with fourteen equivalent IrFe4Ir8 cuboctahedra, edges with six equivalent FeIr12 cuboctahedra, edges with twelve equivalent IrFe4Ir8 cuboctahedra, faces with four equivalent FeIr12 cuboctahedra, and faces with sixteen equivalent IrFe4Ir8 cuboctahedra. There are a spread of Ir–Ir bond distances ranging from 2.65–2.76 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on AgIr by Materials Project

IrAg is Magnesium-derived structured and crystallizes in the hexagonal P-6m2 space group. The structure is three-dimensional. Ir is bonded to six equivalent Ir and six equivalent Ag atoms to form IrAg6Ir6 cuboctahedra that share corners with eighteen equivalent IrAg6Ir6 cuboctahedra, edges with six equivalent IrAg6Ir6 cuboctahedra, edges with twelve equivalent AgAg6Ir6 cuboctahedra, faces with eight equivalent IrAg6Ir6 cuboctahedra, and faces with twelve equivalent AgAg6Ir6 cuboctahedra. All Ir–Ir bond lengths are 2.76 Å. All Ir–Ag bond lengths are 2.92 Å. Ag is bonded to six equivalent Ir and six equivalent Ag atoms to form AgAg6Ir6 cuboctahedra that share corners with eighteen equivalent AgAg6Ir6 cuboctahedra, edges with six equivalent AgAg6Ir6 cuboctahedra, edges with twelve equivalent IrAg6Ir6 cuboctahedra, faces with eight equivalent AgAg6Ir6 cuboctahedra, and faces with twelve equivalent IrAg6Ir6 cuboctahedra. All Ag–Ag bond lengths are 2.76 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on CoIr by Materials Project

IrCo crystallizes in the hexagonal P-6m2 space group. The structure is three-dimensional. Ir is bonded to six equivalent Ir and six equivalent Co atoms to form distorted IrCo6Ir6 cuboctahedra that share corners with eighteen equivalent IrCo6Ir6 cuboctahedra, edges with six equivalent IrCo6Ir6 cuboctahedra, edges with twelve equivalent CoCo6Ir6 cuboctahedra, faces with eight equivalent IrCo6Ir6 cuboctahedra, and faces with twelve equivalent CoCo6Ir6 cuboctahedra. All Ir–Ir bond lengths are 2.67 Å. All Ir–Co bond lengths are 2.57 Å. Co is bonded to six equivalent Ir and six equivalent Co atoms to form distorted CoCo6Ir6 cuboctahedra that share corners with eighteen equivalent CoCo6Ir6 cuboctahedra, edges with six equivalent CoCo6Ir6 cuboctahedra, edges with twelve equivalent IrCo6Ir6 cuboctahedra, faces with eight equivalent CoCo6Ir6 cuboctahedra, and faces with twelve equivalent IrCo6Ir6 cuboctahedra. All Co–Co bond lengths are 2.67 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on IrW by Materials Project

WIr crystallizes in the hexagonal P-6m2 space group. The structure is three-dimensional. W is bonded to six equivalent W and six equivalent Ir atoms to form WIr6W6 cuboctahedra that share corners with eighteen equivalent WIr6W6 cuboctahedra, edges with six equivalent WIr6W6 cuboctahedra, edges with twelve equivalent IrIr6W6 cuboctahedra, faces with eight equivalent WIr6W6 cuboctahedra, and faces with twelve equivalent IrIr6W6 cuboctahedra. All W–W bond lengths are 2.81 Å. All W–Ir bond lengths are 2.77 Å. Ir is bonded to six equivalent W and six equivalent Ir atoms to form IrIr6W6 cuboctahedra that share corners with eighteen equivalent IrIr6W6 cuboctahedra, edges with six equivalent IrIr6W6 cuboctahedra, edges with twelve equivalent WIr6W6 cuboctahedra, faces with eight equivalent IrIr6W6 cuboctahedra, and faces with twelve equivalent WIr6W6 cuboctahedra. All Ir–Ir bond lengths are 2.81 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on HoSi3Ir by Materials Project

HoIrSi3 crystallizes in the tetragonal I4mm space group. The structure is three-dimensional. Ho is bonded in a 8-coordinate geometry to four equivalent Ir and twelve Si atoms. All Ho–Ir bond lengths are 3.32 Å. There are a spread of Ho–Si bond distances ranging from 3.07–3.36 Å. Ir is bonded in a 5-coordinate geometry to four equivalent Ho and five Si atoms. There are one shorter (2.33 Å) and four longer (2.37 Å) Ir–Si bond lengths. There are two inequivalent Si sites. In the first Si site, Si is bonded in a distorted single-bond geometry to four equivalent Ho, one Ir, and four equivalent Si atoms. All Si–Si bond lengths are 2.56 Å. In the second Si site, Si is bonded in a distorted bent 120 degrees geometry to four equivalent Ho, two equivalent Ir, and two equivalent Si atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Co3Ir by Materials Project

IrCo3 is beta-derived structured and crystallizes in the hexagonal P-6m2 space group. The structure is three-dimensional. Ir is bonded to six equivalent Ir and six equivalent Co atoms to form IrCo6Ir6 cuboctahedra that share corners with six equivalent IrCo6Ir6 cuboctahedra, corners with twelve equivalent CoCo12 cuboctahedra, edges with six equivalent IrCo6Ir6 cuboctahedra, edges with twelve equivalent CoCo9Ir3 cuboctahedra, faces with six equivalent IrCo6Ir6 cuboctahedra, and faces with fourteen CoCo12 cuboctahedra. All Ir–Ir bond lengths are 2.62 Å. All Ir–Co bond lengths are 2.61 Å. There are two inequivalent Co sites. In the first Co site, Co is bonded to twelve Co atoms to form CoCo12 cuboctahedra that share corners with six equivalent CoCo12 cuboctahedra, corners with twelve equivalent IrCo6Ir6 cuboctahedra, edges with eighteen CoCo12 cuboctahedra, faces with two equivalent IrCo6Ir6 cuboctahedra, and faces with eighteen CoCo12 cuboctahedra. There are six shorter (2.47 Å) and six longer (2.62 Å) Co–Co bond lengths. In the second Co site, Co is bonded to three equivalent Ir and nine Co atoms to form distorted CoCo9Ir3 cuboctahedra that share corners with eighteen equivalent CoCo9Ir3 cuboctahedra, edges with six equivalent IrCo6Ir6 cuboctahedra, edges with twelve CoCo12 cuboctahedra, faces with six equivalent IrCo6Ir6 cuboctahedra, and faces with fourteen CoCo12 cuboctahedra. All Co–Co bond lengths are 2.62 Å.

36 MATERIALS SCIENCE↗
NASA NTRS2015

Insulation Resistance Degradation in Ni-BaTiO3 Multilayer Ceramic Capacitors

Insulation resistance (IR) degradation in Ni-BaTiO3 multilayer ceramic capacitors has been characterized by the measurement of both time to failure and direct-current (DC) leakage current as a function of stress time under highly accelerated life test conditions. The measured leakage current-time dependence data fit well to an exponential form, and a characteristic growth time SD can be determined. A greater value of tau(sub SD) represents a slower IR degradation process. Oxygen vacancy migration and localization at the grain boundary region results in the reduction of the Schottky barrier height and has been found to be the main reason for IR degradation in Ni-BaTiO3 capacitors. The reduction of barrier height as a function of time follows an exponential relation of phi (𝑡)=phi (0)e(exp -2Κt), where the degradation rate constant 𝐾=𝐾o𝑒(𝐸𝑘/𝑘𝑇) is inversely proportional to the mean time to failure (MTTF) and can be determined using an Arrhenius plot. For oxygen vacancy electromigration, a lower barrier height phi(0) will favor a slow IR degradation process, but a lower phi(0) will also promote electronic carrier conduction across the barrier and decrease the insulation resistance. As a result, a moderate barrier height phi(0) (and therefore a moderate IR value) with a longer MTTF (smaller degradation rate constant 𝐾) will result in a minimized IR degradation process and the most improved reliability in Ni-BaTiO3 multilayer ceramic capacitors.

dielectric degradation↗
DOE OSTI2025

Enhancing Acidic Oxygen Evolution Activity by Controlling Oxidation State of Iridium

Iridium oxides with high oxidation states have been reported to be effective in enhancing the acidic oxygen evolution reaction (OER) performance. Herein, we develop ultrasmall IrO x nanoparticles (NPs) over titanium nitride (TiN), which undergoes surface oxidation under oxidative conditions to form oxygen-modified TiN (oxi-TiN), enabling the formation of highly oxidized Ir δ+ (δ > 4). This IrO x /oxi-TiN catalyst delivers higher Ir mass activity than commercial IrO 2 , while comparable stability is maintained. The superior OER activity of IrO x /oxi-TiN is further demonstrated in a proton exchange membrane water electrolyzer (PEMWE), requiring only 1.88 V to reach 3 A cm −2 , achieving the U.S. Department of Energy 2025 target (1.90 V at 3 A cm −2 ). In situ X-ray absorption spectroscopy (XAS) confirms that the superior OER activity of IrO x /oxi-TiN originates from highly oxidized Ir δ+ under OER conditions. Further, density functional theory (DFT) calculations reveal a general correlation between the oxidation state of Ir and OER overpotential. Specifically, the introduction of interfacial oxygen at the Ir/TiN interface increases the oxidation state of deposited Ir δ+ from δ < 4 to δ > 4, decreasing the OER overpotential. This study highlights the critical role of high oxidation states of Ir δ+ in enhancing OER activity, providing guidance for the development of advanced acidic OER catalysts.

In situ measurements↗
DOE OSTI2025

Enhancing Acidic Oxygen Evolution Activity by Controlling Oxidation State of Iridium

Iridium oxides with high oxidation states have been reported to be effective in enhancing the acidic oxygen evolution reaction (OER) performance. In this work, we develop ultrasmall IrO x nanoparticles (NPs) over titanium nitride (TiN), which undergoes surface oxidation under oxidative conditions to form oxygen‐modified TiN (oxi‐TiN), enabling the formation of highly oxidized Ir δ+ (δ > 4). This IrO x /oxi‐TiN catalyst delivers higher Ir mass activity than commercial IrO 2 , while comparable stability is maintained. The superior OER activity of IrO x /oxi‐TiN is further demonstrated in a proton exchange membrane water electrolyzer (PEMWE), requiring only 1.88 V to reach 3 A cm −2 , achieving the U.S. Department of Energy 2025 target (1.90 V at 3 A cm −2 ). In situ X‐ray absorption spectroscopy (XAS) confirms that the superior OER activity of IrO x /oxi‐TiN originates from highly oxidized Ir δ+ under OER conditions. Density functional theory (DFT) calculations reveal a general correlation between the oxidation state of Ir and OER overpotential. Specifically, the introduction of interfacial oxygen at the Ir/TiN interface increases the oxidation state of deposited Ir δ+ from δ < 4 to δ > 4, decreasing the OER overpotential. This study highlights the critical role of high oxidation states of Ir δ+ in enhancing OER activity, providing guidance for the development of advanced acidic OER catalysts.

58 GEOSCIENCES↗
DOE OSTI2021

Noncovalent Immobilization of Pentamethylcyclopentadienyl Iridium Complexes on Ordered Mesoporous Carbon for Electrocatalytic Water Oxidation

The attachment of molecular catalysts to conductive supports for the preparation of solid-state anodes is important for the development of devices for electrocatalytic water oxidation. The preparation and characterization of three molecular cyclopentadienyl iridium(III) complexes, Cp*Ir(1-pyrenyl(2-pyridyl)ethanolate-κO,κN)Cl (1) (Cp* = pentamethylcyclopentadienyl), Cp*Ir(diphenyl(2-pyridyl)methanolate-κO,κN)Cl (2), and [Cp*Ir(4-(1-pyrenyl)-2,2'-bipyridine)Cl]Cl (3), as precursors for electrochemical water oxidation catalysts, are reported. These complexes contain aromatic groups that can be attached via noncovalent π-stacking to ordered mesoporous carbon (OMC). The resulting iridium-based OMC materials (Ir-1, Ir-2, and Ir-3) were tested for electrocatalytic water oxidation leading to turnover frequencies (TOFs) of 0.9–1.6 s -1 at an overpotential of 300 mV under acidic conditions. The stability of the materials is demonstrated by electrochemical cycling and X-ray absorption spectroscopy analysis before and after catalysis. Theoretical studies on the interactions between the molecular complexes and the OMC support provide insight onto the noncovalent binding and are in agreement with the experimental loadings.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗