Directed Assembly of Large-Area Periodic Arrays of Epitaxially Aligned Single-Crystal Gold and Silver Nanoplates

Noble metal nanoplates represent a remarkable class of nanostructures that provide a highly compatible geometry for integration with wafer-based processing since the combination unites two systems that have an inherently two-dimensional character. The seed-mediated growth of noble metal nanoplates requires the use of seeds lined with parallel stacking faults so as to provide a two-dimensional break in symmetry in an otherwise isotropic metal. Although such seeds are routinely synthesized using colloidal pathways, equivalent pathways did not exist for substrate-based seeds arranged in periodic arrays. The inability to fabricate these seeds fundamentally limited the breadth of nanostructure architectures accessible to the substrate platform. In this presentation, we demonstrate a benchtop nanofabrication route for assembling substrate-based gold seeds lined with stacking faults and used them to synthesize large-area periodic arrays of epitaxially aligned single-crystal gold and silver nanoplates with hexagonal or triangular geometry. The overall process, which is carried out using benchtop techniques, combines nanoimprint lithography, vapor-phase directed assembly of crystalline seeds, and liquid-phase seed-mediated synthesis. Taken together, the work advances the practices and knowhow needed to fully exploit one of the most important nanostructure architectures and, from a broader perspective, contributes to an ongoing effort that sees single-crystal nanomaterials integrated into device platforms.<br/> <br/>R. D. Neal, Z. R. Lawson, W. J. Tuff, K. Xu, V. Kumar, M. T. Korsa, M. Zhukovskyi, M. R. Rosenberger, J. Adam, J. P. Camden, R. A. Hughes, S. Neretina, Large-Area Periodic Arrays of Atomically Flat Single-Crystal Gold Nanotriangles formed Directly on Substrate Surfaces. <i>Small </i><b>2022</b>, <i>18</i>, 2205780.<br/><br/>T. B. Demille, R. D. Neal, A. S. Preston, Z. Liang, A. G. Oliver, R. A. Hughes, S. Neretina, Epitaxially Aligned Single-Crystal Gold Nanoplates formed in Large-Area Arrays at High Yield. <i>Nano Research</i> <b>2022</b>, <i>15</i>, 296−303.<br/><br/>S. D. Golze, R. A. Hughes, S. Rouvimov, R. D. Neal, T. B. Demille, S. Neretina, Plasmon-Mediated Synthesis of Periodic Arrays of Gold Nanoplates using Substrate-Immobilized Seeds Lined with Planar Defects. <i>Nano Letters</i> <b>2019</b>, <i>19</i>, 5653−5660.