Sterically Programmed Dynamic-Covalent Self-Assembly Enables High-Throughput Engineering of Supramolecular Nanotubes.

Supramolecular self-assembly provides an attractive route to organic semiconducting nanotubes, yet concurrent control over tube diameter, helicity and wall number remains elusive. Here we report a dynamic-covalent strategy that converts a single perylene diimide aldehyde precursor (PDIOA) into a family of nanotubes through one-pot imine formation with small amines. Combining microscopy, diffraction and DFT analysis, we show that steric congestion at the ortho position programs a helical packing mode that nucleates and propagates tubular architectures. Crucially, the nanotube inner diameter can be predictably "dialled" by the steric demand of the amine: increasing steric bulk progressively contracts the tube cavity. Enantiomeric amines further translate molecular chirality into opposite supramolecular helicities, affording mirror-image helical nanotubes. Moreover, tuning monomer concentration and solvent composition enables uniform double- and triple-walled nanotubes, demonstrating controllable wall-layer engineering within the same chemical platform. The resulting nanotubes exhibit dimension-dependent photoconductive responses, linking programmable nanoscale structure to optoelectronic function. This work establishes a modular, high-throughput and recyclable route to chiral, multiwalled perylene diimide nanotubes with independently addressable diameter, helicity and wall number.