Cocrystal Engineering of Molecular Nanocarbon

The practical application of molecular nanocarbons in photocatalysis is often constrained by their short exciton diffusion lengths and limited light-harvesting capabilities. Cocrystal engineering represents a promising avenue to modulate the photophysical properties of organic semiconductors through precise donor-acceptor (D-A) integration. In this study, we demonstrate that cocrystallization of a series of modularly synthesized, ladder-type molecular nanocarbons (nDP) with 1,2,4,5-tetracyanobenzene (TCNB) or octafluoronaphthalene (OFN) affords a new class of charge-transfer cocrystals (CTCs) with tailored optoelectronic properties. Notably, the DP-TCNB exhibits exceptional photocatalytic performance for hydrogen peroxide production, achieving a remarkable evolution rate of 40500 μmol g⁻¹ h⁻¹ and an apparent quantum yield of 9.62% at 420 nm in a water/benzyl alcohol biphasic system. Detailed structural, spectroscopic, and electrochemical analyses reveal that the enhanced performance originates from strong intermolecular charge-transfer interactions, which lead to a reduced bandgap, prolonged charge carrier lifetime, and efficient suppression of electron-hole recombination. This work not only presents a high-performance molecular photocatalyst but also establishes cocrystal engineering as a robust and generalizable strategy for advancing molecular nanocarbon-based sustainable energy conversion.