Controlled Self-Assembly of Clamparene-Based Cocrystals for Tunable Supramolecular Architectures and Their Application in Photothermal Conversion

Controllable self-assembly provides an effective strategy for constructing ordered molecular architectures with tunable structures and functions. However, realizing precise control over the topological evolution of supramolecular systems in the solid state remains a considerable challenge. Here, we report a clamparene-based (CLP) donor–acceptor cocrystallization system with tetracyanobenzene (TCNB) that enables molecular-level regulation of supramolecular topology and photothermal behavior. The π-electron-rich CLP and electron-deficient TCNB form charge-transfer (CT) complexes through exo-wall π···π interactions. By tuning the donor-to-acceptor ratio, two distinct crystalline supramolecular polymers were obtained: a linear topology (TCNB@CLPα-1) and a zigzag topology (TCNB@CLPα-2). Single-crystal X-ray diffraction, spectroscopic analyses, and DFT calculations reveal that the CT interactions between CLP and TCNB narrow the HOMO–LUMO gap and facilitate nonradiative relaxation processes. Benefiting from these interactions, the crystalline supramolecular polymers exhibit efficient photothermal conversion under simulated sunlight, with TCNB@CLPα-1 showing superior performance due to a greater number of repeating CT units. This work demonstrates that structural modulation at the molecular scale provides a viable route to achieving controllable topologies and tunable macroscopic functions in crystalline supramolecular materials.