The emergence of amorphous materials approaching the single-layer limit.

Amorphous materials with thickness thinned down to the single-layer limit have attracted increasing interest due to their well-defined disorder and emerging unique properties, such as disorder-dominated electronic states, high-density unsaturated coordination, enhanced quantum confinement, These features could enable innovative applications in electronics, photoelectronics, catalysis, and beyond. In this perspective, we provide an overview of recent advances in two-dimensional (2D) amorphous materials approaching the single-layer limit. We first introduce newly-developed key structural descriptors for these systems, including local bonding, topological disorder, and chemical composition. Next, we highlight fabrication breakthroughs across diverse material classes, such as amorphous carbon, oxides/hydroxides, metals, transition metal dichalcogenides (TMDCs), and metal/covalent-organic frameworks (MOFs/COFs). The resulting properties, spanning electrical/electrocatalytic properties, mechanical toughness, photoelectric response, and topological electronic states, are subsequently discussed. Finally, we outline current challenges and future opportunities in this rapidly evolving field.