A novel MXene-bridged Z-scheme ZnO@Nb2CTx MXene@carbon nitride nanosheets photocatalyst for efficient enrofloxacin degradation

Abstract

A Z-scheme photocatalyst, ZnO@Nb2CTx MXene@carbon nitride nanosheets (ZNC), is synthesized by the hydrothermal and electrostatic self-assembly strategy. The degradation test shows that ZNC photocatalyst has an enhanced photocatalytic efficiency of Enrofloxacin (ENR) degradation under visible light irradiation. The ENR removing rate has reached 98.2 % after 40 min light irradiation and has a degradation rate of 0.0961 min−1, which is 4.78 times higher than pure ZnO and 3.987 times higher than CNNS. Besides, a possible ENR degradation pathway was studied via LC-MS method. Furthermore, in-situ high resolution XPS spectroscopy and DFT calculation confirmed the direction of electron flow in the ZNC photocatalyst, highlighting that its improved degradation efficiency primarily stems from the introduction of the MXene electron transport layer, which promotes efficient charge transfer and separation of electron-hole pair. This study provides a guidance to design highly efficient Z-scheme photocatalyst for ENR degradation.