Bioinspired Face-to-Face Supramolecular Co-Assembled Arrays Enabled by Cation-π Interaction With Programmed Electron...

Photocatalytic hydrogen peroxide (H₂O₂) production has emerged as a sustainable alternative to the energy-intensive anthraquinone process, yet its efficiency remains fundamentally limited by inefficient charge transport and electron-hole recombination. Here, we report a bioinspired strategy for constructing face-to-face supramolecular co-assembled arrays (FF-SCAAs), in which periodic co-facial organization serves as a structural platform for programming electron transport pathways toward enhanced photocatalytic H₂O₂ production. Inspired by the signal-transport arrays of natural compound eyes, cationic trioxatriangulenium (TOTA⁺) and electron-rich benzophenanthrene derivatives are integrated into highly ordered FF-SCAAs through directional cation-π interaction. The resulting FF-SCAAs feature enhanced dipole moments and favorable orbital alignment, enabling extended charge transport channels while intrinsically suppressing electron-hole recombination. On this basis, FF-SCAAs achieve a H₂O₂ photosynthesis rate up to 6.46 mmol g^-1 h^-1 with a solar-to-chemical conversion efficiency of 0.84%. Ultrafast spectroscopic and mechanistic studies demonstrate that the periodic co-facial arrays promote directional excited-state electron migration and selective two-electron oxygen reduction pathways for H₂O₂ generation. Furthermore, the in situ generated H₂O₂ is fed into a cascade wastewater treatment system and consumed in a downstream Fenton process for efficient degradation of phenolic pollutants.