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DOE OSTI · 1883974

Thin-Film Paradigm to Probe Interfacial Diffusion during Solid-State Metathesis Reactions

McAuliffe, Rebecca D.·Huang, Guanglong·Montiel, David·Mehta, Apurva·Davis, Ryan C.·Petrova, Victoria·Browning, Katie L.·Neilson, James R.·Liu, Ping·Thornton, Katsuyo·Veith, Gabriel M.
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Abstract

We highlight a paradigm for studying complex reaction mechanisms that guide the synthesis of materials. Thin films of FeCl 2 and Na 2 S 2 were deposited to study the metathesis reaction to form FeS 2 and NaCl. In situ X-ray reflectivity was used to monitor the interface between materials, which revealed a slow, impeded reaction at high temperatures as compared to previous studies using powder samples. AC impedance and X-ray photoelectron spectroscopy provided insight into distribution of elements and conductivity of the phases present during the reaction, and phase-field modeling was used to elucidate the diffusion of ions throughout the thin-film bilayers. Here, the use of thin-film bilayers provides a simplified system to study solid-state metathesis reactions and highlights the complexity of diffusion at solid-state interfaces.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRYDiffusionIonsLayersMetathesisVesicles

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McAuliffe, Rebecca D., Huang, Guanglong, Montiel, David, Mehta, Apurva, Davis, Ryan C., Petrova, Victoria, Browning, Katie L., Neilson, James R., Liu, Ping, Thornton, Katsuyo, Veith, Gabriel M.. 2022-07-01. Thin-Film Paradigm to Probe Interfacial Diffusion during Solid-State Metathesis Reactions. https://doi.org/10.1021/acs.chemmater.2c00303

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