In situ XANES and GID characterization of 2D GaN growth on liquid metal catalysts

Liquid metal catalysts (LMCats) are a promising platform for the synthesis and growth of large, defect-free and highly crystalline two-dimensional (2D) materials such as graphene and hexagonal boron nitride. More recently, a larger range of 2D materials have been produced this way, including GaN, which is of high interest for applications in nanoelectronics. With the proposed experiments, we aim at investigating the structure of 2D GaN crystals during their growth on liquid gallium alloys. The electronic structure and chemical environment of Ga species will be tracked in situ using XANES, while the in-plane lattice constant, crystallite size and strains of the 2D GaN crystals will be tracked using GID. These experiments will enable to unravel the growth mechanism of 2D GaN on the surface of liquid metals and probe in depth the chemical mechanisms at play.

液态金属催化剂（LMCats）是用于合成与生长大型无缺陷、高结晶度二维（2D）材料（如石墨烯与六方氮化硼）的极具潜力的技术平台。近期，通过该方法已制备出更多种类的二维材料，包括在纳米电子学应用中备受关注的氮化镓（GaN）。本研究拟开展相关实验，旨在探究液态镓合金表面生长的二维氮化镓晶体的微观结构。我们将采用X射线吸收近边结构谱（XANES）原位追踪镓物种的电子结构与化学环境，同时利用掠入射X射线衍射（GID）表征二维氮化镓晶体的面内晶格常数、晶粒尺寸与应变。本系列实验将阐明液态金属表面二维氮化镓的生长机制，并深入探究其背后的核心化学作用机理。