Investigation on the steered adsorption of aspirin through a constructed electronic transport tunnel by incorporating Ti into graphene with DFT approach

Abstract

Focused on the decontamination of pharmaceutical pollutants via an adsorption approach, the adsorptive mode and capacity of adsorbents have been explored with a strategy by incorporating Ti into graphene (TG) frame using the density functional theory (DFT). Aspirin is used as a model molecule and pristine graphene (PG) as comparative substrate in this study. It is notified for PG, aspirin is adsorbed with a C-ring parallel orientation. It presents a weak physical adsorption through π-π interaction with an energy value of −0.846 eV. Whereas, a stronger chemical adsorption of aspirin on surface of TG with even lager adsorption energy of −2.772 eV is confirmed. The analysis based on Hirshfeld population and electronic distribution show the electrons of aspirin transfer to TG with an electron transport channel of O-Ti-C, which contribute to steer the enhanced adsorption. Furthermore, band structure and density of state display more densely and successive semimetal feature with a very slight band gap for TG, confirming the enhanced harvesting ability for wide wavelength regions of solar light. Consequently, the present investigation demonstrates by incorporating metal into PG frame, a strong adsorption material toward pharmaceutical contaminant could be achieved.