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Creators/Authors contains: "Zachman, Michael J."

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  1. As a recent advancement in reaction engineering, magnetic induction heating (MIH) is utilized to initiate the intended reactions by enabling the self-heating of the ferromagnetic catalyst particles. While MIH can be energy-efficient and industrially scalable, its full potential has been underappreciated in catalysis because of the perception that MIH is merely an alternative heating approach. Unexpectedly, we show that the MIH-triggered reaction could go beyond standard thermal catalysis. Specifically, by probing the representative Pt/Fe3O4 catalysts with CO oxidation in both thermal and MIH modes with consistent temperature profiles and catalyst structures, we found that the MIH mode boosts the reactivity more than 25 times by modifying Pt−FeOx interfacial synergies and promoting facile oxidation of the adsorbed carbonyl species by atomic oxygen. As we preliminarily observed, this beneficial MIH catalysis can be translational to other thermal reactions, potentially paving the way to launch MIH catalysis as a distinct reaction category. 
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  2. Abstract Developing novel lead‐free ferroelectric materials is crucial for next‐generation microelectronic technologies that are energy efficient and environment friendly. However, materials discovery and property optimization are typically time‐consuming due to the limited throughput of traditional synthesis methods. In this work, we use a high‐throughput combinatorial synthesis approach to fabricate lead‐free ferroelectric superlattices and solid solutions of (Ba0.7Ca0.3)TiO3(BCT) and Ba(Zr0.2Ti0.8)O3(BZT) phases with continuous variation of composition and layer thickness. High‐resolution x‐ray diffraction (XRD) and analytical scanning transmission electron microscopy (STEM) demonstrate high film quality and well‐controlled compositional gradients. Ferroelectric and dielectric property measurements identify the “optimal property point” achieved at the composition of 48BZT–52BCT. Displacement vector maps reveal that ferroelectric domain sizes are tunable by varying {BCT–BZT}Nsuperlattice geometry. This high‐throughput synthesis approach can be applied to many other material systems to expedite new materials discovery and properties optimization, allowing for the exploration of a large area of phase space within a single growth. image 
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  3. Abstract Copper-based catalyst is uniquely positioned to catalyze the hydrocarbon formations through electrochemical CO2reduction. The catalyst design freedom is limited for alloying copper with H-affinitive elements represented by platinum group metals because the latter would easily drive the hydrogen evolution reaction to override CO2reduction. We report an adept design of anchoring atomically dispersed platinum group metal species on both polycrystalline and shape-controlled Cu catalysts, which now promote targeted CO2reduction reaction while frustrating the undesired hydrogen evolution reaction. Notably, alloys with similar metal formulations but comprising small platinum or palladium clusters would fail this objective. With an appreciable amount of CO-Pd1moieties on copper surfaces, facile CO*hydrogenation to CHO*or CO-CHO*coupling is now viable as one of the main pathways on Cu(111) or Cu(100) to selectively produce CH4or C2H4through Pd-Cu dual-site pathways. The work broadens copper alloying choices for CO2reduction in aqueous phases. 
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