Dynamically-generated TiO2 active site on MXene Ti3C2: Boosting reactive desulfurization

Ti3C2 MXene with dynamically-generated TiO2 active site for boosting catalytic oxidative desulfurization has been researched. The two-dimensional Ti3C2 MXene, with abundant interface engineering and loosely layered structure, was synthesized through selectively etching of aluminum (Al) layer in Ti3AlC2 MAX. The desulfurization activity of Ti3C2 MXene is higher than that of bulk Ti3AlC2 MAX. Compared with Ti3AlC2 MAX, the expanded slit layer provides more pores and cavities to accelerate the mass transfer of the reaction. Also, the excellent dispersion and interfacial affinity are conducive to the further access of MXene with the substrate in diesel. More than 87% of sulfides in real diesel can be removed with Ti3C2 MXene as the catalyst. Specifically, the dynamically-generated active sites originate from the continuous activation of molecular oxygen and Ti3C2 MXene, which favors the enhance of catalytic activity. Meanwhile, by detecting and analyzing the oxidizing products of various aromatic sulfides, the results show that the MXene interlayers serve as a reaction micro-cavity and are beneficial to the adsorption and removal of the sulfone. This work not only illustrates that MXene can be used in thermally excited catalytic systems, but also provides an example around the construction of dynamically generated active sites to extend the life of the catalyst.