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DOE OSTI · 2573120

Mesoporous Amorphous High-Entropy Oxide Films: Unlocking Enhanced Redox Activity

Wang, Qingju [Univ. of Tennessee, Knoxville, TN (United States)]·Li, Meijia [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)] (ORCID:0000000261137428)·Siniard, Kevin M. [Univ. of Tennessee, Knoxville, TN (United States)] (ORCID:0000000302419705)·Driscoll, Darren M. [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)] (ORCID:0000000188598016)·Ivanov, Alexander S. [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)] (ORCID:0000000281936673)·Liu, Jue [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)] (ORCID:000000024453910X)·Yang, Shize [Yale Univ., New Haven, CT (United States)]·Zhang, Junyan [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)]·Polo-Garzon, Felipe [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)] (ORCID:0000000265076183)·Houston, Austin [Univ. of Tennessee, Knoxville, TN (United States)] (ORCID:0009000587774686)·Duscher, Gerd [Univ. of Tennessee, Knoxville, TN (United States)]·Yang, Zhenzhen [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)] (ORCID:0000000202334747)·Dai, Sheng [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States); Univ. of Tennessee, Knoxville, TN (United States)] (ORCID:0000000280463931)
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Abstract

High-entropy oxides (HEOs) represent a frontier in catalyst design via entropy-stabilized solid solution formation. However, their catalytic efficiency is limited by their bulk and dense nature. This work presents a strategic approach to tackle this challenge by fabricating mesoporous amorphous HEO films (MA-HEOF) possessing maximized active site utilization efficiency. The success hinges on the as-developed geometric engineering strategy via controlled deposition–precipitation to confine the amorphous HEO thin film on the surface of mesoporous channels. The unique structure of MA-HEOF was elucidated via microscopy-, X-ray-, and neutron-based techniques, which were manifested by enriched surface-activated lattice oxygen and enhanced redox activity, as confirmed by isotope studies. Besides, the MA-HEOF could stabilize and modulate the properties of integrated noble metal sites, enhancing their redox activity in diverse reactions. In conclusion, the approaches and insights presented herein provide guidance on maximizing the utilization efficiency of high-entropy materials in catalysis and beyond.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRYCatalystsMetalsOxidationPlatinumSilicaheterogeneous catalysishigh-entropy oxidehydrogenationmesoporous materialsurface confinement

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Wang, Qingju [Univ. of Tennessee, Knoxville, TN (United States)], Li, Meijia [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)] (ORCID:0000000261137428), Siniard, Kevin M. [Univ. of Tennessee, Knoxville, TN (United States)] (ORCID:0000000302419705), Driscoll, Darren M. [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)] (ORCID:0000000188598016), Ivanov, Alexander S. [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)] (ORCID:0000000281936673), Liu, Jue [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)] (ORCID:000000024453910X), Yang, Shize [Yale Univ., New Haven, CT (United States)], Zhang, Junyan [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)], Polo-Garzon, Felipe [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)] (ORCID:0000000265076183), Houston, Austin [Univ. of Tennessee, Knoxville, TN (United States)] (ORCID:0009000587774686), Duscher, Gerd [Univ. of Tennessee, Knoxville, TN (United States)], Yang, Zhenzhen [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)] (ORCID:0000000202334747), Dai, Sheng [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States); Univ. of Tennessee, Knoxville, TN (United States)] (ORCID:0000000280463931). 2025-06-24. Mesoporous Amorphous High-Entropy Oxide Films: Unlocking Enhanced Redox Activity. https://doi.org/10.1021/acscatal.5c01591

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