Vacancy ordering and lithium insertion in III2VI3 nanowires

Abstract

Superlattice structures resulting from vacancy ordering have been observed in many materials. Here we report vacancy ordering behavior in III2VI3 nanowires. The formation of layer-like structural vacancies has been achieved during the synthesis of In2Se3 nanowires through a vapor-transport route. Doping In2Se3 nanowires with small amounts of Ga during synthesis can completely change the structural vacancy ordering from a layer-like to a screw-like pattern for (Inx Ga1−x )2Se3 nanowires. Lithium atoms can fill in the layer-like structural vacancies of In2Se3 nanowires and generate new types of vacancy and lithium atom ordering superlattices. The screw-patterned vacancies of (Inx Ga1−x )2Se3 nanowires show reversible lithium insertion. Our results contribute to the understanding of structure property correlations of III2VI3 materials used in lithium ion storage, photovoltaics, and phase change memory.