Fundamentals of charge transport in two-dimensional framework materials

Two-dimensional framework materials (2DFMs) have emerged as a transformative class of synthetic organic 2D crystal materials, in which molecular building blocks and/or metal nodes are linked through covalent or coordination bonds to form layered networks stabilized by π–π interactions. Their modular design allows atomic-level control over electronic configurations, enabling novel quantum phenomena and tunable functionalities. Over the past decade, strategic exploitation of intralayer π-extended conjugation and interlayer electronic coupling has revolutionized charge transport engineering in 2DFMs, driving advancements in (opto-)electronics, energy storage and quantum materials. In this Review, we provide a coherent overview of structural design strategies, charge transport mechanisms and cutting-edge characterization methodologies for electrically conductive 2DFMs. We emphasize recent progress elucidating key factors governing charge transport properties and intricate structure–property relationships. Finally, we discuss promising directions for advancing this rapidly evolving field that bridges atomic precision with solid-state physics, offering unprecedented opportunities to design electronic materials from the bottom up.