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DOE OSTI · 1963051

Shape-Controlled NaTaO 3 by Flux-Mediated Synthesis

Hong, Kootak·Tan, Shaun·McDermott, Matthew J.·Huang, Tianyi·Babbe, Finn·Kodalle, Tim·Gallant, Max·Seo, Sehun·Toma, Francesca M.·Persson, Kristin A.·Yang, Yang·Sutter‐Fella, Carolin M.
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Abstract

NaTaO 3 is a stable and wide bandgap n-type semiconductor material with many different applications. Here, a flux-mediated synthesis method is presented for NaTaO 3 resulting in highly distinctive, substrate covering shapes via precursor chemistry variation at comparatively low temperatures. It is found that the microstructure of the resulting NaTaO 3 films can be varied from nanocubes to smooth thin films. These shapes and surface chemistries can be correlated by employing density functional theory calculations and surface sensitive X-ray photoemission spectroscopy. This study provides guidance on how to synthesize the material and tailor its shape and surface termination for different applications. Finally, as a proof of concept of one possible application, NaTaO 3 is applied to perovskite solar cells as the electron transport layer, resulting in conversion efficiencies of >19%. Further, this study provides a new strategy for designing ternary oxide thin films for renewable energy applications.

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38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEAR CHEMISTRYcharge transport layerscrystallization pathwaysflux-mediated synthesesperovskite solar cellssurface chemistry

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Hong, Kootak, Tan, Shaun, McDermott, Matthew J., Huang, Tianyi, Babbe, Finn, Kodalle, Tim, Gallant, Max, Seo, Sehun, Toma, Francesca M., Persson, Kristin A., Yang, Yang, Sutter‐Fella, Carolin M.. 2022-09-02. Shape-Controlled NaTaO 3 by Flux-Mediated Synthesis. https://doi.org/10.1002/adfm.202206641

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