title: Atomic-layer-deposition oxide nanoglue for sodium ion batteries.
abstract: Atomic-layer-deposition (ALD) coatings have been increasingly used to improve battery performance. However, the electrochemical and mechanistic roles remain largely unclear, especially for ALD coatings on electrodes that undergo significant volume changes (up to 100%) during charging/discharging. Here we investigate an anode consisting of tin nanoparticles (SnNPs) with an ALD-Al2O3 coating. For the first time, in situ transmission electron microscopy unveiled the dynamic mechanical protection of the ALD-Al2O3 coating by coherently deforming with the SnNPs under the huge volume changes during charging/discharging. Battery tests in coin-cells further showed the ALD-Al2O3 coating remarkably boosts the cycling performance of the Sn anodes, comparing with those made of bare SnNPs. Chemomechanical simulations clearly revealed that a bare SnNP debonds and falls off the underlying substrate upon charging, and by contrast the ALD-Al2O3 coating, like ion-conductive nanoglue, robustly anchors the SnNP anode to the substrate during charging/discharging, a key to improving battery cycle performance.
authors.affiliation: Department of Materials Science and Engineering, University of Maryland , College Park, Maryland 20742, United States.
authors.forename: Xiaogang
authors.initials: X
authors.lastname: Han
authors.forename: Yang
authors.initials: Y
authors.lastname: Liu
authors.forename: Zheng
authors.initials: Z
authors.lastname: Jia
authors.forename: Yu-Chen
authors.initials: YC
authors.lastname: Chen
authors.forename: Jiayu
authors.initials: J
authors.lastname: Wan
authors.forename: Nicholas
authors.initials: N
authors.lastname: Weadock
authors.forename: Karen J
authors.initials: KJ
authors.lastname: Gaskell
authors.forename: Teng
authors.initials: T
authors.lastname: Li
authors.forename: Liangbing
authors.initials: L
authors.lastname: Hu