Carbon
materials are regarded as a promising adsorbent for the
adsorption of volatile organic compounds (VOCs). However, their adsorption
behaviors are usually compromised at ambient conditions, attributed
to the competitive VOCs adsorption with water vapor. In this study,
we demonstrated that the selectivity for toluene than water of carbon
can be effectively enhanced by introducing more sp2-carbon
with two-dimensional nanosheets stacked. The multilayer carbon nanosheets
enriched with sp2-carbon (CNS-MCA) exhibit a 151°
H2O-contact angle, indicating hydrophobicity. Dynamic adsorption
behaviors revealed that CNS-MCA retain 71% of their toluene adsorption
capacity (91 mg/g) even at 60% relative humidity. Density functional
theory (DFT) calculations, static adsorption studies, in situ Raman
spectroscopy, and time-resolved in situ nuclear magnetic resonance
(NMR) spectroscopy collectively indicate that toluene exhibits enhanced
adsorption and selectivity due to π–π* interactions
between its aromatic rings and the sp2-carbon. Conversely,
water adsorption is attenuated, attributed to the reduced availability
of surface-exposed hydrogen bonds associated with sp2-carbon
and the inherent hydrophobic nature of multilayer graphene. This study
extends a novel solution for the enhancement of VOCs adsorption under
humid conditions.