Defect‐Templated Phase Engineering in Atomically Thin Metals
Abstract
ABSTRACT Achieving deterministic control over crystal phase at the atomic limit remains a fundamental challenge for atomically thin metals, where subtle differences in atomic registry can produce large changes in electronic and optical functionality. Here, we establish interfacial defect templating as a general materials‐design strategy for phase engineering in confined two‐dimensional metals, using monolayer silver as a model system. By tailoring the defect chemistry of a graphene overlayer, we selectively stabilize two competing crystalline phases of two‐dimensional Ag at the graphene/SiC interface: a near‐commensurate phase promoted by vacancy and line defects in epitaxial graphene, and a denser phase favored beneath intrinsically sp 3 ‐rich zero‐layer graphene. Multimodal characterization reveals distinct lattice registries, electronic structures, and charge transfer to the graphene overlayer for each phase. First‐principles calculations show that phase selectivity arises from a competition between kinetically favored nucleation pathways and thermodynamically preferred packing configurations, explaining both controlled phase formation and long‐term evolution. The defect‐programmed Ag phases exhibit strongly contrasting linear and nonlinear optical responses, enabling phase‐tunable optical functionality at atomic thickness. More broadly, this work reframes defects as deliberate design elements for programming structure–property relationships in confined two‐dimensional metals.
Article Details
Authors (26)
Arpit Jain
Boyang Zheng
Sawani Datta
Max‐Planck‐Institut Für Festkörperforschung Stuttgart Germany
Kanchan Ulman
Department of Physics National University of Singapore Singapore Singapore
Jakob Henz
Institute of Physics and Center for Soft Nanoscience (SoN) University of Münster Münster Germany
Matthew Wei‐Jun Liu
Department of Materials Science and Engineering The Pennsylvania State University University Park Pennsylvania USA
Van Dong Pham
Paul‐Drude‐Institut Für Festkörperelektronik Leibniz‐Institut Im Forschungsverbund Berlin e. V. Berlin Germany
Wen He
New Cornerstone Science Laboratory, MOE Key Laboratory for Analytical Science of Food Safety and Biology, College of Chemistry
Chengye Dong
Li‐Syuan Lu
Department of Materials Science and Engineering The Pennsylvania State University University Park Pennsylvania USA
Alexander Vera
Department of Materials Science and Engineering The Pennsylvania State University University Park Pennsylvania USA
Nader Sawtarie
Department of Chemical and Petroleum Engineering University of Pittsburgh Pittsburgh Pennsylvania USA
Wesley Auker
Materials Research Institute The Pennsylvania State University University Park Pennsylvania USA
Ke Wang
Tianjin Medical University Cancer Institute and Hospital Tianjin China
Bob Hengstebeck
Materials Research Institute The Pennsylvania State University University Park Pennsylvania USA
Zachary W. Henshaw
Department of Physics and Engineering Physics Juniata College Huntingdon Pennsylvania USA
Shreya Mathela
Department of Chemistry The Pennsylvania State University University Park Pennsylvania USA
Maxwell Wetherington
Materials Research Institute The Pennsylvania State University University Park Pennsylvania USA
William H. Blades
Department of Physics and Engineering Physics Juniata College Huntingdon Pennsylvania USA
Kenneth Knappenberger
Department of Chemistry The Pennsylvania State University University Park Pennsylvania USA
Ursula Wurstbauer
Institute of Physics and Center for Soft Nanoscience (SoN) University of Münster Münster Germany
Su Ying Quek
Department of Materials Science and Engineering National University of Singapore Singapore Singapore
Ulrich Starke
Max‐Planck‐Institut Für Festkörperforschung Stuttgart Germany
Shengxi Huang
Vincent H. Crespi
Department of Physics The Pennsylvania State University University Park Pennsylvania USA
Joshua A. Robinson