Linz Mario, Bühner Florian, Paulus Daniel, Hennerici Lukas, Guo Yiran, Mereacre Valeriu, Mansfeld Ulrich, Seipenbusch Martin, Kita Jaroslaw, Moos Ralf
Department of Functional Materials, University of Bayreuth, Universitätsstraße 30, 95447, Bayreuth, Germany.
Bayerisches Zentrum für Batterietechnik, Weiherstraße 26, 95448, Bayreuth, Germany.
Adv Mater. 2024 Feb;36(7):e2308294. doi: 10.1002/adma.202308294. Epub 2023 Dec 7.
The powder aerosol deposition (PAD) method is a process to manufacture ceramic films completely at room temperature. Since the first reports by Akedo in the late 1990s, much research has been conducted to reveal the exact mechanism of the deposition process. However, it is still not fully understood. This work tackles this challenge using core-shell particles. Two coated oxides, Al O core with a SiO shell and LiNi Mn Co O core with a LiNbO shell, are investigated. Initially, the element ratios Al:Si and Ni:Nb of the powder are determined by energy-dispersive X-ray spectroscopy (EDX). In a second step, the change in the element ratios of Al:Si and Ni:Nb after deposition is investigated. The element ratios from powder to film strongly shift toward the shell elements, indicating that the particles fracture and only the outer parts of the particles are deposited. In the last step, this work investigates cross-sections of the deposited films with scanning transmission electron microscopy (STEM combined with EDX and an energy-selective back-scattered electron (EsB) detector to unveil the element distribution within the film itself. Therefore, the following overall picture emerges: particles impact on the substrate or on previously deposited particle, fracture, and only a small part of the impacting particles that originate from the outer part of the impacting particle gets deposited.
