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DOE OSTI · 2881799

Alumina–Titania Nanolaminate Condensers for Hot Programmable Catalysis

Abstract

Nanolaminates composed of thin alternating layers of Al2O 3 and TiO 2 (ATO) were engineered by using atomic layer deposition as the dielectric material for a Pt-on-carbon catalytic condenser. Investigation assessed synthesis parameters including the deposition temperature, Al 2 O 3 and TiO 2 layer thicknesses, total number of layers, and a capping Al 2 O 3 layer on the maximum charge accumulation in the Pt catalyst. The highest capacitance ATO configuration demonstrated a specific capacitance of ∼1200 nF/cm 2 with working voltages of ±5 V, enabling the storage of 4 × 10 13 electrons or holes per cm 2 at room temperature. The ATO devices exhibited enhanced capacitance at elevated temperatures of up to 400 °C, suggesting the suitability of these materials for high-temperature applications. Adsorption of carbon monoxide on the Pt/C-ATO device characterized by grazing incidence infrared spectroscopy showed changes in the surface binding energy of 13.1 ± 0.8 kJ/mol for an applied external voltage bias of ±1 V.

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Oh, Kyung-Ryul [Univ. of Minnesota, Minneapolis, MN (United States)] (ORCID:0000000349541310), Walton, Amber [Univ. of Minnesota, Minneapolis, MN (United States)] (ORCID:0000000306001613), Chalmers, Jason A. [Univ. of Minnesota, Minneapolis, MN (United States)], Hopkins, Justin A. [Univ. of Minnesota, Minneapolis, MN (United States)] (ORCID:0000000323253919), Canavan, Jesse R. [Univ. of Minnesota, Minneapolis, MN (United States)], Onn, Tzia Ming [Univ. of Cambridge (United Kingdom)] (ORCID:0000000275230746), Scott, Susannah L. [Univ. of Minnesota, Minneapolis, MN (United States); Univ. of California, Santa Barbara, CA (United States)] (ORCID:0000000311610499), Frisbie, C. Daniel [Univ. of Minnesota, Minneapolis, MN (United States)] (ORCID:0000000247352228), Dauenhauer, Paul J. [Univ. of Minnesota, Minneapolis, MN (United States)] (ORCID:0000000158101953). 2024-07-03. Alumina–Titania Nanolaminate Condensers for Hot Programmable Catalysis. https://doi.org/10.1021/acsmaterialslett.4c00652

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