Front Cover: Mechanochemistry toward Organic “Salt” via Integer‐Charge‐Transfer Cocrystal Strategy for Rapid, Efficient, and Scalable Near‐Infrared Photothermal Conversion (ChemSusChem 14/2023)

Abstract

The Front Cover shows integer‐charge‐transfer cocrystals are self‐assembled via multiple intermolecular hydrogen bonds with one electron transferred from donor to acceptor unit for high‐efficiency (∼87 %) NIR photothermal conversion. “D‐A pairs” as the basic “micro‐stacking units” in cocrystals guarantee strong donor‐acceptor interactions and excellent photothermal performance. Amorphous cocrystals synthesized by one‐step mechanochemical method exhibit good photo/thermal stability, which is highly desirable in practical large‐scale solar‐harvesting/conversion applications without the puzzle of maintaining an ideal stacking structure. More information can be found in the Research Article by S.‐L. Chen et al.

Dual-rotor strategy for organic cocrystals with enhanced near-infrared photothermal conversion

“…3a-c and S16-S18 †). [23][24][25][26] As shown in Fig. S16a and b to S18a and b, † the DFQ/DTQ/MTQ cocrystals display the excited-state absorption (ESA) bands peaked at around 330 nm under 400 nm-laser excitation.…”

“…And the second lifetime s 2 is assigned to the vibrational relaxation (VR) process from the excited states ( 1 CT 1 ) to the ground states ( 1 CT 0 ). 1,10,13,[23][24][25][26] From the perspective of D/A molecular structure, the detailed IC transition and VR can be produced easily by the free rotation of the single-bond rotor (-CH 3 ) from the donors, 11,12 and the double-bond rotor being in the form of []C(C^N) 2 ] in the ground states but being in the form of [-C(C^N) 2 ] in the excited states from the conjugated quinoid acceptors. 13 These nonradiative decay processes together help the cocrystals efficiently convert the absorbed light into heat energy.…”