Sutter Eli, Sutter Peter
Department of Mechanical and Materials Engineering, University of Nebraska-Lincoln, Lincoln, NE, 68588, USA.
Nebraska Center for Materials and Nanoscience, University of Nebraska-Lincoln, Lincoln, NE, 68588, USA.
Small. 2023 Oct;19(41):e2302592. doi: 10.1002/smll.202302592. Epub 2023 Jun 13.
The integration of dissimilar materials into heterostructures is a mainstay of modern materials science and technology. An alternative strategy of joining components with different electronic structure involves mixed-dimensional heterostructures, that is, architectures consisting of elements with different dimensionality, for example, 1D nanowires and 2D plates. Combining the two approaches can result in hybrid architectures in which both the dimensionality and composition vary between the components, potentially offering even larger contrast between their electronic structures. To date, realizing such heteromaterials mixed-dimensional heterostructures has required sequential multi-step growth processes. Here, it is shown that differences in precursor incorporation rates between vapor-liquid-solid growth of 1D nanowires and direct vapor-solid growth of 2D plates attached to the wires can be harnessed to synthesize heteromaterials mixed-dimensional heterostructures in a single-step growth process. Exposure to mixed GeS and GeSe vapors produces GeS Se van der Waals nanowires whose S:Se ratio is considerably larger than that of attached layered plates. Cathodoluminescence spectroscopy on single heterostructures confirms that the bandgap contrast between the components is determined by both composition and carrier confinement. These results demonstrate an avenue toward complex heteroarchitectures using single-step synthesis processes.
将不同材料整合到异质结构中是现代材料科学与技术的支柱。一种连接具有不同电子结构组件的替代策略涉及混合维度异质结构，即由具有不同维度的元素组成的结构，例如一维纳米线和二维平板。将这两种方法结合起来可以形成混合结构，其中组件之间的维度和组成都会发生变化，这可能会在它们的电子结构之间提供更大的对比度。到目前为止，实现这种异质材料混合维度异质结构需要顺序多步生长过程。在此，研究表明，可以利用一维纳米线的气-液-固生长与附着在纳米线上的二维平板的直接气-固生长之间前驱体掺入速率的差异，在单步生长过程中合成异质材料混合维度异质结构。暴露于混合的GeS和GeSe蒸气中会产生GeS Se范德华纳米线，其S:Se比远大于附着的层状平板。对单个异质结构进行阴极发光光谱分析证实，组件之间的带隙对比度由组成和载流子限制共同决定。这些结果展示了一条使用单步合成工艺实现复杂异质结构的途径。
