Pyromellitic Diimide-Based Donor–Acceptor MOF with Panchromatic Absorption for High-Efficiency Photothermal Conversion
Silang Chen, Hao Zeng, Ci Kong, Feixiang Cheng, Jian‐Jun Liu
Abstract
The incorporation of donor–acceptor components into metal–organic frameworks (MOFs) is an effective approach for developing efficient near-infrared (NIR) photothermal conversion materials; yet, their precise structural design and synthetic methodologies still present significant challenges. In this work, we present a distinctive MOF material Zn 2 (bpPDI)(TTFTB)·solvent ( MOF 1 ) constructed by the coordinated assembly of donor–acceptor components, featuring a tetrathiafulvalene tetrabenzoate (TTFTB) electron donor and a bis-pyridyl-substituted pyromellitic diimide (bpPDI) electron acceptor. The material demonstrates significant intrinsic intermolecular electron-transfer capability and possesses a long-lived TTFTB •+ radical cation and a bpPDI •– radical anion. These characteristics enable panchromatic absorption spanning the visible to the second near-infrared (NIR-II) region, thus allowing efficient NIR photothermal conversion. Under NIR light irradiation, MOF 1 achieves efficient photothermal conversion (Δ T max = 137 °C under 0.5 W cm –2 laser exposure), including rare NIR-II photothermal conversion capabilities, while exhibiting excellent thermal stability and cycling durability.