Atomic Scale Tracking of Single Layer Oxide Formation: Self‐Peeling and Phase Transition in Solution. Issue 7 (27th May 2021) - Zhang, Junyu
Abstract: Liquid phase electron microscopy (TEM) is used to track the formation of In2 O3 ultrathin nanosheet in solution at atomic scale. This observation reveals that the formation of few atomic layer nanosheet goes through a complicated phase transition process from InCl3 . 3H2 O to In(OH)3 and then to In2 O3 . Interestingly, the intermediate InCl3 . 3H2 O nanosheet can grow via either layer by layer or the strain‐driven enation growth from precursor solution. Moreover, in situ TEM results and density functional theory (DFT) calculations demonstrate that the oleylamine is responsible for the self‐peeling process. These findings can provide atomic‐level insight for the understanding of how 2D nanomaterial grows and transforms in solution. Abstract : In this work, by using liquid cell electron microscopy, the growth trajectories of indium oxide (In2 O3 ) nanosheets are tracked at atomic scale. First, the intermediate InCl3 . 3H2 O crystal bottom‐up growth from precursor solution via the layer‐by‐layer growth or the strain‐driven enation growth method is observed. Subsequently, the crystal undergoes a self‐driven "top‐down" dissociation process including self‐peeling and phase transition, which produces porous In2 O3 nanosheets accompanying the release of HCl and H2 O molecules.