Interfacial design principles in mixed-dimensional perovskite heterostructures: Bridging nanostructure chemistry and device functionality

Metal halide perovskite nanostructures, including quantum dots (QDs), nanowires (NWs), and nanoplates (NPs), offer a chemically tunable platform for next-generation optoelectronics, yet their performance is ultimately governed not by bulk composition but by surface and interfacial chemistry. In this comprehensive review, we establish ligand and interfacial chemistry as the central design paradigms for mixed-dimensional perovskite heterostructures. We systematically discuss how ligand coordination governs morphology, defect passivation, and electronic coupling across individual 0D, 1D, and 2D nanostructures, and how mixed-dimensional interfaces, including QD/NW, QD/NP, and NW/NP junctions, are chemically programmed through ligand-mediated band alignment, ionic regulation, and charge-transfer dynamics. These molecular-level design principles are then contextualized within three optoelectronic platforms, solar cells, LEDs, and photodetectors, where interfacial ligand engineering translates into enhanced efficiency, stability, and spectral tunability. Emerging directions including dynamic ligands, lead-free compositions, eco-friendly processing, and neuromorphic functionality are discussed alongside key challenges in interfacial reproducibility and scalable manufacturing. This review advances a unified chemical framework wherein ligand-regulated interfacial physics bridges molecular design and macroscopic device performance.