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At least 973 records · Page 54
All sourcesNASA NTRSDOE OSTI
DOE OSTI2024

Embedding Reverse Electron Transfer Between Stably Bare Cu Nanoparticles and Cation‐Vacancy CuWO 4

Cu nanoparticles (NPs) have attracted widespread attention in electronics, energy, and catalysis. However, conventionally synthesized Cu NPs face some challenges such as surface passivation and agglomeration in applications, which impairs their functionalities in the physicochemical properties. Here, the issues above by engineering an embedded interface of stably bare Cu NPs on the cation-vacancy CuWO 4 support is addressed, which induces the strong metal-support interactions and reverse electron transfer. Various atomic-scale analyses directly demonstrate the unique electronic structure of the embedded Cu NPs with negative charge and anion oxygen protective layer, which mitigates the typical degradation pathways such as oxidation in ambient air, high-temperature agglomeration, and CO poisoning adsorption. Kinetics and in situ spectroscopic studies unveil that the embedded electron-enriched Cu NPs follow the typical Eley-Rideal mechanism in CO oxidation, contrasting the Langmuir-Hinshelwood mechanism on the traditional Cu NPs. This mechanistic shift is driven by the Coulombic repulsion in anion oxygen layer, enabling its direct reaction with gaseous CO to form the easily desorbed monodentate carbonate.

Cu nanoparticles↗
DOE OSTI2020

Direct observation of 3D atomic packing in monatomic amorphous materials

Liquids and solids are two fundamental states of matter. Although the structure of crystalline solids has long been solved by crystallography, our understanding of the 3D atomic structure of liquids and amorphous materials remained speculative. In 1952, Frank hypothesized that icosahedral order is the prevalent atomic motif in monatomic liquids. Over the past six decades, there have been a great deal of experimental, computational and theoretical studies to understand the structure of liquids and amorphous materials. A polytetrahedral packing model was proposed to explain the 3D atomic structure of monatomic liquids and amorphous materials, in which icosahedral order is a key feature. The icosahedral order has also been found to play an important role in the structure of metallic glasses and quasicrystals. Here we advance atomic electron tomography to determine for the first time the 3D atomic positions in monatomic amorphous materials, including a Ta thin film and two Pd nanoparticles. Despite the different chemical composition and synthesis methods, we observe that pentagonal bipyramids are the most abundant atomic motifs in these amorphous materials. Contrary to the traditional understanding, the pentagonal bipyramids do not assemble full icosahedra, but are closely connected with each other to form networks that extend to medium-range scale. Our molecular dynamic simulations, coupled with experimental results, further reveal that the 3D atomic structure of monatomic liquids is similar to the experimental amorphous material. Moreover, we find that the pentagonal bipyramid networks, prevalent in monatomic liquids, rapidly grow in size and form a fraction of full icosahedra during the quench from a liquid to a metallic glass state, providing a possible new picture of structural evolution through the glass transition.

Yuan, Yakun↗
DOE OSTI2025

Long-Range Metal–Sorbent Interactions Determine CO 2 Capture and Conversion in Dual-Function Materials

Carbon capture and utilization involve multiple energy- and cost-intensive steps. Dual-function materials (DFMs) can reduce these demands by coupling CO 2 adsorption and conversion into a single material with two functionalities: a sorbent phase and a metal for catalytic CO 2 conversion. The role of metal catalysts in the conversion process seems salient from previous work, but the underlying mechanisms remain elusive and deserve deeper investigation to achieve maximum utilization of the two phases. Here, for this work, preformed colloidal Ru nanoparticles were deposited onto a “NaOx”/Al 2 O 3 sorbent to prepare prototypical DFMs with controlled phases for CO 2 capture and hydrogenation to CH 4 . Ru addition was found to double the high-temperature CO 2 adsorption capacity by activating the “NaOx”/Al 2 O 3 sorbent phase during a reductive pretreatment step. Most importantly, low Ru loadings were sufficient to ensure maximum CO 2 adsorption and conversion. This was attributed to the key role of the metal–sorbent interactions, wherein Ru was required to hydrogenate strongly bound CO 2 on the “NaO x ”/Al 2 O 3 sorbent to CH 4 via the H 2 activated on Ru. This interaction facilitated rate-determining carbonate migration and subsequent hydrogenation at the metal–sorbent interface. Overall, Ru controlled the CO 2 hydrogenation reaction rate, while the “NaO x ”/Al 2 O 3 sorbent dictated the CO 2 uptake capacity. By controlling metal–sorbent interactions at the molecular level, we demonstrate the critical role of the two phases and their synergy, facilitating the design of DFMs with maximum CO 2 capture and conversion efficiency.

carbon capture↗
DOE OSTI2021

Large-Scale Synthesis of Semiconducting Cu(In,Ga)Se2 Nanoparticles for Screen Printing Application

During the last few decades, the interest over chalcopyrite and related photovoltaics has been growing due the outstanding structural and electrical properties of the thin-film Cu(In,Ga)Se2 photoabsorber. More recently, thin film deposition through solution processing has gained increasing attention from the industry, due to the potential low-cost and high-throughput production. To this end, the elimination of the selenization procedure in the synthesis of Cu(In,Ga)Se2 nanoparticles with following dispersion into ink formulations for printing/coating deposition processes are of high relevance. However, most of the reported syntheses procedures give access to tetragonal chalcopyrite Cu(In,Ga)Se2 nanoparticles, whereas methods to obtain other structures are scarce. Herein, we report a large-scale synthesis of high-quality Cu(In,Ga)Se2 nanoparticles with wurtzite hexagonal structure, with sizes of 10–70 nm, wide absorption in visible to near-infrared regions, and [Cu]/[In + Ga] ≈ 0.8 and [Ga]/[Ga + In] ≈ 0.3 metal ratios. The inclusion of the synthesized NPs into a water-based ink formulation for screen printing deposition results in thin films with homogenous thickness of ≈4.5 µm, paving the way towards environmentally friendly roll-to-roll production of photovoltaic systems.

36 MATERIALS SCIENCE↗
DOE OSTI2025

Facet-Dependent Hydrogen Evolution Reaction on M 2 P (M = Ni, Co, Fe) Single Crystals

Transition-metal phosphides (MPs) are promising earth-abundant catalysts for hydrogen evolution reactions (HERs) due to their remarkable activity and stability. To further improve their properties, facet control is a key strategy. The growth of shape-selected nanoparticles may substantially enhance electrocatalytic activity, but this approach requires fundamental studies of facet-specific catalytic properties. There are only a few reports on the facet effects of MPs, which leads to a limited understanding of the activity of each facet and hampers catalyst design. Here, in this study, we grew large hexagonal-prism-shaped single crystals of three representative M 2 P (M = Ni, Co, and Fe) catalysts using metal flux routes. Two facets of M 2 P single crystals were tested to study facet-dependent HER activities, and it was consistently demonstrated that for all M 2 P crystals, a tip facet [(0001) for Ni 2 P/Fe 2 P and (010) for Co 2 P] had a higher activity than the side facet [(101̅0) for Ni 2 P/Fe 2 P and (100) for Co 2 P]. HER activity between the same facet elucidated the activity ordered between different transition metals as Fe 2 P > Co 2 P > Ni 2 P under low-potential regions. At high applied potentials, this trend is reversed due to the differences in Tafel slopes, with Ni 2 P becoming the most active catalyst, such that the activity of the (0001) facet of Ni 2 P approaches that of Pt. The calculated surface density of states (DOS) of each facet and its local curvature were found to be a useful descriptor for the activity trends among different transition metals of the same facets.

Co2P↗
DOE OSTI2020

Intermetallic Nanocatalysts from Heterobimetallic Group 10–14 Pyridine-2-thiolate Precursors

Intermetallic compounds are atomically ordered inorganic materials containing two or more transition metals and main-group elements in unique crystal structures. Intermetallics based on group 10 and group 14 metals have shown enhanced activity, selectivity, and durability in comparison to simple metals and alloys in many catalytic reactions. While high-temperature solid-state methods to prepare intermetallic compounds exist, softer synthetic methods can provide key advantages, such as enabling the preparation of metastable phases or of smaller particles with increased surface areas for catalysis. In this work, we study a generalized family of heterobimetallic precursors to binary intermetallics, each containing a group 10 metal and a group 14 tetrel bonded together and supported by pincer-like pyridine-2-thiolate ligands. Upon thermal decomposition, these heterobimetallic complexes form 10–14 binary intermetallic nanocrystals. Experiments and density functional theory (DFT) computations help in better understanding the reactivity of these precursors toward the synthesis of specific intermetallic binary phases. Using Pd 2 Sn as an example, we demonstrate that nanoparticles made in this way can act as uniquely selective catalysts for the reduction of nitroarenes to azoxyarenes, which highlights the utility of the intermetallics made by our method. Employing heterobimetallic pincer complexes as precursors toward binary nanocrystals and other metal-rich intermetallics provides opportunities to explore the fundamental chemistry and applications of these materials.

10-14 intermetallics↗
DOE OSTI2023

Theoretical assessments of Pd–PdO phase transformation and its impacts on H 2 O 2 synthesis and decomposition pathways

The direct synthesis of H 2 O 2 from O 2 and H 2 provides a green pathway to produce H 2 O 2 , a popular industrial oxidant. Here, in this study, we theoretically investigate the effects of Pd oxidation states, coordination environments, and particle sizes on primary H 2 O 2 selectivities, assessed by calculating the ratio of rate constants for the formation of H 2 O 2 (via OOH* reduction; k O–H ) and the decomposition of OOH* (via O–O cleavage; k O–O ). For Pd metals, the k O–H /k O–O ratio decreased from 10 -4 for Pd(111) to 10 -10 for the Pd 13 cluster at 300 K, indicating poorer H 2 O 2 selectivity as Pd particle size decreases and low primary selectivities for H 2 O 2 overall. As the oxygen chemical potential increases and metals form surface and bulk oxides, the perturbation of Pd–Pd ensemble sites by lattice O atoms results in selectivities that become dramatically higher than unity. For instance, at 300 K, the k O–H /k O–O ratio increases significantly from 10 -4 to 10 9 to 10 16 as Pd(111) oxidizes to Pd 5 O 4 /Pd(111) and to PdO(100), respectively. In contrast, such selectivity enhancements are not observed for surface and bulk oxides that persistently contain rows of more metallic, undercoordinated Pd–Pd ensemble sites, such as PdO(101)/Pd(100) and PdO(101). These Pd–Pd ensembles are also absent when smaller Pd nanoparticles fully oxidize, indicating that smaller PdO clusters can be more selective for H 2 O 2 synthesis. These trends for primary H 2 O 2 selectivities were found to inversely correlate with trends for H 2 O 2 decomposition rates via O–O bond cleavage, demonstrating that catalysts with high primary H 2 O 2 selectivity can also hinder H 2 O 2 decomposition. Ab initio thermodynamic calculations are used to estimate the thermodynamically favored phase among Pd, PdO/Pd and PdO in O 2 , H 2 O 2 /H 2 O, and O 2 /H 2 environments. These results are combined to show that smaller Pd nanoparticles are more prone to be oxidized at lower oxygen chemical potentials, upon which they become more selective than larger Pd particles for H 2 O 2 synthesis.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2022

CO oxidation on MgAl 2 O 4 supported Ir n : activation of lattice oxygen in the subnanometer regime and emergence of nuclearity-activity volcano

CO oxidation on Pt group metals is affected by the metal size and reducibility of the oxide support. In this study, we report that Ir supported on MgAl 2 O 4 , traditionally considered non-reducible, exhibits properties similar to reducible oxides when the Ir size is in the subnanometer regime. To show this effect, we synthesized subnanometer Ir clusters and compared their properties to single atoms and nanoparticles (1–1.5 nm). The CO oxidation activity is highest on Ir 0.6–0.8nm while showing distinctly different reaction orders in CO and O 2 (0, +0.4), than single atoms (1, 0) and nanoparticles (–1, +1). Microcalorimetry, in situ X-ray absorption, and infrared spectroscopies show that the CO-saturated Ir 0.6–0.8nm clusters could adsorb and activate O 2 despite binding CO more strongly than nanoparticles. Density functional theory calculations on CO saturated Ir 4 clusters suggest that the increased activity is due to the ability to activate O 2 on oxygen vacancies at the Ir–MgAl 2 O 4 interface. The findings show the important effect of the metal nuclearity on the support and catalyst properties and can guide future design of CO oxidation catalysts.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2022

Porous Colloidal Nanoparticles as Injectable Multimodal Contrast Agents for Enhanced Geophysical Sensing

Injecting fluids into underground geologic structures is crucial for the development of long-term strategies for managing captured carbon and facilitating sustainable energy extraction operations. Here, we have previously reported that the injection of metal–organic frameworks (MOFs) into the subsurface can enhance seismic monitoring tools to track fluids and map complex structures, reduce risk, and verify containment in carbon storage reservoirs because of their absorption capacity of low-frequency seismic waves. Here, we demonstrate that water-based Cr/Zn/Zr MOF colloidal suspensions (nanofluids) are multimodal geophysical contrast agents that enhance near-wellbore logging tools. Based on experimental fluid-only measurements, MIL-101(Cr), ZIF-8, and UiO-66 nanofluids have distinct complex conductivity and/or low-field nuclear magnetic resonance (NMR) signatures that are relevant to field-deployed technologies, implying the potential to enhance near-wellbore monitoring of CO 2 injection and associated processes with downhole logging tools. Small- and wide-angle X-ray scattering characterization of ~0.5 wt % MIL-101(Cr) suspensions confirmed phase stability and provided insight into the fractal nature of colloidal nanoparticles. Finally, low-field (2 MHz) NMR measurements of MIL-101(Cr) nanofluid injection into a prototypical Berea sandstone demonstrate how paramagnetic high-surface area MOFs may dominate the relaxation times of hydrogen-bearing fluids in porous geologic matrices, enhancing the mapping of near-surface and near-wellbore transport pathways and advancing sustainable subsurface energy technologies.

NMR↗
DOE OSTI2020

Boosting the activity of transition metal carbides towards methane activation by nanostructuring

The interaction of methane with pristine surfaces of bulk MoC and Mo 2 C is known to be weak. In contrast, a series of X-ray photoelectron spectroscopy (XPS) experiments, combined with thermal desorption mass spectroscopy (TDS), for MoC y (y = 0.5–1.3) nanoparticles supported on Au(111)—which is completely inert towards CH 4 —show that these systems adsorb and dissociate CH 4 at room temperature and low CH 4 partial pressure. This industrially-relevant finding has been further investigated with accurate density functional theory (DFT) based calculations on a variety of MoC y supported model systems. The DFT calculations reveal that the MoC y /Au(111) systems can feature low C–H bond scission energy barriers, smaller than the CH 4 adsorption energy. Our theoretical results for bulk surfaces of Mo 2 C and MoC show that a simple Brønsted–Evans–Polanyi (BEP) relationship holds for C–H bond scission on these systems. However, this is not the case for methane activation on the MoC y nanoparticles as a consequence of their unique electronic and chemical properties. Finally, the discovery that supported molybdenum carbide nanoparticles are able to activate methane at room temperature paves the road towards the design of a new family of active carbide catalysts for methane activation and valorisation, with important implications in climate change mitigation and carbon cycle closure.

36 MATERIALS SCIENCE↗
DOE OSTI2020

The Role of Protons and Hydrides in the Catalytic Hydrogenolysis of Guaiacol at the Ruthenium Nanoparticle-water Interface

The mechanistic roles of free hydronium ions, surface hydrides, and interfacial protons during guaiacol hydrodeoxygenation (HDO) on ruthenium nanoparticles are established. As guaiacol adsorbs on Ru, it loses its strong aromaticity and undergoes a rapid H-shift from its hydroxyl to meta carbons (in relation to its hydroxyl group), leading enol and keto surface isomers to exist in chemical equilibrium. HDO occurs via a hydridic H-adatom (H*) attack to the enol, followed by a kinetically relevant C-O bond rupture step, during which water shuttles the hydroxyl proton, enabling its intramolecular attack to the methoxy, evolving a high charged [Ru(s)-(C6H5O-)…(H+)…OCH3]† transition state. The competing HYD begins with a rapid H* attack to the keto, before a second, kinetically relevant H* attack, without proton involvement. Water, despite shifting the thermodynamics towards the more polar surface keto, promotes HDO to a much greater extent than HYD, because of its dual catalytic roles—it mobilizes hydroxyl proton (Brønsted acid) to cleave the strong C-O bond, synchronizing with the Ru metal surface (base) function that stabilizes the resulting [Ru(s)-(C6H5O-)…(H+)…OCH3]† transition state, and the water layers solvate this charged transition state, further reducing its free energy. Free hydronium ions do catalyze a separate homogeneous enol-keto isomerization, but this reaction is kinetically unrelated to HDO catalysis. This mechanistic picture explains the strong effects of polar protic solvent in hydrodeoxygenation, highlighting (i) the requirements of surface hydrides and interfacial protons acting in tandem to complete a HDO turnover and (ii) the cooperative role of protic solvent and metal surface in breaking the aromaticity and stabilizing charged reactive precursors and transition states.

Shangguan, Junnan↗
DOE OSTI2024

Irreversible Catalyst Deactivation Mechanisms of PdO/γ-Al 2 O 3 Catalysts for Lean Methane Oxidation

PdO/γ-Al 2 O 3 catalysts suffer from gradual and irreversible catalyst deactivation under lean CH 4 oxidation conditions, especially in a wet feed. Here, time-resolved CO chemisorption DRIFTS measurements are conducted systematically on a series of PdO/γ-Al 2 O 3 catalysts to probe the surface reactivity of PdO nanoparticles after various in situ pretreatments. At 80 °C, CO barely adsorbs on fully oxidized PdO surfaces but interacts with coordinatively unsaturated Pd sites, causing gradual reduction of the PdO surfaces. This results in the formation of characteristic IR bands on various metallic Pd 0 sites. By monitoring and comparing the formation kinetics of these IR bands on samples before and after CH 4 oxidation, we theorize that the irreversible catalyst deactivation during CH 4 oxidation is caused by PdO surface reconstruction, in which coordinatively unsaturated Pd sites gradually become fully coordinated by oxygen. Effectively, the surface reconstruction leads to the formation of a passivation layer on the PdO nanoparticles, which hinders their ability in activating CH 4 , and hence the subsequent oxidation reaction. Temperature-programmed reduction with CO as the reductant (CO-TPR) reveals that the passivation layer formed during CH 4 oxidation is significant enough to increase the reduction temperature of PdO nanoparticles of the 3.0% PdO/γ-Al 2 O 3 samples, although such an effect is less obvious for the 0.4% PdO/γ-Al 2 O 3 samples. On the other hand, it is also discovered that the passivation layer is not completely inert. Under certain reaction conditions, with some being relatively mild, such as low-temperature CO oxidation in a net lean atmosphere and in the presence of H 2 O, the passivation layer can undergo structure change which results in regeneration or even activation of CH 4 oxidation activity of an already deactivated catalyst. Additionally, it is discovered that the fully coordinated Pd–O surface is a metastable phase under CH 4 oxidation conditions. In the presence of H 2 O and at ambient temperatures, surfaces with coordinatively unsaturated Pd sites are thermodynamically more favorable.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2022

Reactivity of Pd–MO 2 encapsulated catalytic systems for CO oxidation

In this work, we present an investigation aimed at characterizing and understanding the synergistic interactions in encapsulated catalytic structures between the metal core (i.e., Pd) and oxide shell (i.e., TiO 2 , ZrO 2 , and CeO 2 ). Encapsulated catalysts were synthesized using a two-step procedure involving the initial colloidal synthesis of Pd nanoparticles (NPs) capped by various ligands and subsequent sol–gel encapsulation of the NPs with porous MO 2 (M = Ti, Zr, Ce) shells. The encapsulated catalytic systems displayed higher activity than the Pd/MO 2 supported structures due to unique physicochemical properties at the Pd–MO 2 interface. Pd@ZrO 2 exhibited the highest catalytic activity for CO oxidation. Results also suggested that the active sites in Pd encapsulated by an amorphous ZrO 2 shell structure were significantly more active than the crystalline oxide encapsulated structures at low temperatures. Furthermore, CO DRIFTS studies showed that Pd redispersion occurred under CO oxidation reaction conditions and as a function of the oxide shell composition, being observed in Pd@TiO 2 systems only, with potential formation of smaller NPs and oxide-supported Pd clusters after reaction. This investigation demonstrated that metal oxide composition and (in some cases) crystallinity play major roles in catalyst activity for encapsulated catalytic systems.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2021

Reverse-Engineering Strain in Nanocrystallites by Tracking Trimerons

Although strain underpins the behavior of many transition-oxide-based magnetic nanomaterials, it is elusive to quantify. Since the formation of orbital molecules is sensitive to strain, a metal–insulator transition should be a window into nanocrystallite strain. Using three sizes of differently strained Fe 3 O 4 polycrystalline nanorods, the impact of strain on the Verwey transition and the associated formation and dissolution processes of quasiparticle trimerons is tracked. In 40 and 50 nm long nanorods, increasing isotropic strain results in Verwey transitions going from T V ≈ 60 K to 20 K. By contrast, 700 nm long nanorods with uniaxial strain along the (110) direction have T V ≈ 150 K—the highest value reported thus far. A metal–insulator transition, like T V in Fe 3 O 4 , can be used to determine the effective strain within nanocrystallites, thus providing new insights into nanoparticle properties and nanomagnetism.

36 MATERIALS SCIENCE↗
DOE OSTI2023

Additive manufacturing enabled synergetic strengthening of bimodal reinforcing particles for aluminum matrix composites

An additive manufactured TiB 2 /Al-Cu-Mg-Ni composite with a minor amount of Sc was fabricated by laser powder bed fusion (LPBF). The composite shows a yield strength of ~370 MPa, almost doubling the strength of its wrought matrix counterpart, and an elongation of ~7 %. The superior mechanical properties are attributed to a unique micro-nano hierarchical microstructure, consisting of nanoscale and microscale TiB 2 particles dispersed in a matrix of fine aluminum grains (3 µm) together with intragranular intermetallic nanoparticles and nano-cellular networks (cell size 30 nm). The formation of the TiB 2 nanoparticles is the consequence of partial dissolution of the TiB 2 particulates and the enrichment of Sc in the newly formed nanoparticles. Remarkable strengthening effects are achieved by the bimodal TiB 2 particles, intermetallic nanoparticles and intragranular nano-cellular networks. Finally, this study provides new insights into the role of additive manufacturing in tailoring the microstructure of particulate reinforced metal matrix composites (MMCs) with advanced properties.

36 MATERIALS SCIENCE↗
DOE OSTI2021

Plasma catalytic ammonia synthesis on Ni nanoparticles: The size effect

Herein we demonstrate the synthesis of ammonia via atmospheric DBD plasma discharge over nickel nanoparticles supported on silica. We evaluated the performance of nickel nanoparticles with average sizes of 5.6nm and 13.5 nm. The smallest nanoparticle size sample resulted in an ammonia synthesis rate at least 2 times higher than that of the larger nanoparticle size sample and nickel bulk at equimolar composition. This allowed us to observe experimentally, for the first time, the size effect in the area of plasma catalysis. Moreover, the presented results allowed us to investigate a hydrogen sink metal such as nickel under atmospheric plasma conditions and determine the gas composition that resulted beneficial for this surface chemistry.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2025

Low-Temperature Catalyst Redispersion: A Route to Enhanced Stability of Supported Metal Catalysts?

Sintering poses a significant challenge to achieving the long-term stability of supported metal catalysts under reaction conditions. Here, in this study, we report a low-temperature catalyst redispersion mechanism, in which platinum single atoms, which aggregate into nanoparticles under Reverse Water Gas Shift (RWGS) conditions at elevated temperatures, fragment into atomically dispersed species upon cooling. Using multimodal operando characterization combined with first-principles theoretical modeling, we track the structural evolution of Pt single atoms supported on ceria nanodomes, deposited either on ceria or ceria–titania mixed oxides. We find that fragmentation is more pronounced when cooling occurs under RWGS conditions compared to CO alone, owing to a synergistic interplay of the effects of H 2 , CO 2 , and CO. The support architecture has a strong influence on the extent of redispersion: while CO alone induces fragmentation on ceria, interfacial confinement and vacancy pinning at the ceria–titania interface suppress restructuring. In contrast, RWGS conditions overcome these barriers, enabling redispersion across both supports. These findings point toward a pathway for catalyst stabilization via reaction-induced redispersion under mild conditions.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗