Enhanced visible-light photocatalytic degradation activity of Ti3C2/PDIsm via π-π interaction and interfacial charge separation: Experimental and theoretical investigations

Herein, Ti3C2 MXene nanosheets and perylene diimide supramolecular (PDIsm) were successfully combined via a facile self-assembly method. The apparent rate constant of photodegradation for tetracycline hydrochloride (TCH) and Rhodamine B (RhB) of 1%-Ti3C2/PDIsm (0.079 min(-1) and 0.082 min(-1)) were 2.5 times and 7.2 times higher than that of pure PDIsm, respectively. The introduction of Ti3C2 MXene nanosheets is beneficial to the stacking degree of PDIsm and the adsorption capacity of PDIsm for organic pollutants. Moreover, the excellent electrical conductivity of Ti3C2 also promotes the charge separation, which contributes to more photoelectrons participated in the photodegradation reaction of pollutants and thereby the enhanced photocatalytic performance. Additionally, the density functional theory (DFT) calculation also provides strong evidence for the enhanced photocatalytic degradation activity of Ti3C2/PDIsm structure. Meanwhile, the mechanism exploration indicates that h(+), center dot O-2- and O-1(2) play leading roles in the photocatalytic process. This work provides a new insight into using 2D MXenes as co-catalysts to enhance the activity of self-assembled organic materials for environmental remediation.