Unperturbed π-Methyl Electrostatic Interactions Enable Efficient Toluene Adsorption on Graphdiyne Under High Humidity

The efficiency of volatile organic compounds (VOCs) abatement in humid industrial streams is critically hindered by competitive moisture adsorption and the structural vulnerability of conventional adsorbents. Here, we show that a highly hydrophobic graphdiyne (GDY) framework provides a robust platform for sustained VOC capture under highly humid conditions. Dynamic breakthrough measurements demonstrate that GDY maintains > 98% of its toluene uptake (102.5 mg/g) at 50% relative humidity (RH) with excellent cyclic stability, whereas conventional carbonaceous adsorbents usually undergo severe capacity loss. Combined experimental characterization and molecular simulations reveal that the sp-C linkages induce electron density redistribution, fostering π-methyl electrostatic interactions that stabilize toluene adsorption. Meanwhile, the highly delocalized π-electron structure of sp-hybridized carbon suppresses dipole interactions with water molecules and hinders hydrogen bond formation at the adsorbent surface, thereby suppressing competitive adsorption of water. Our study sheds light on the origin of GDY's moisture tolerance and offers practical guidance for the rational design of hydrophobic adsorbents for industrial gas purification.