Formation of Mo_2C/hollow tubular g-C_3N_4 hybrids with favorable charge transfer channels for excellent visible-light-photocatalytic performance

摘要

The pharmaceutical products have becoming ubiquitous in aquatic environment. Photocatalytic degradation is considered as a promising strategy to address this environmental threat. Here we showed new Mo2C/hollow tubular g-C3N4 hybrids (Mo2C/TCN) consisting of well-designed direct Z-scheme heterojunction with favorable charge transfer channels for efficient contaminants degradation. Compare to the traditional Mo2C/g-C3N4 type-I heterojunction reported in the previous literature, the powerful direct Z-scheme heterojunction retains the original redox ability of the component without changing its oxidation and reduction potential. By virtue of the hollow tubular architecture, more incident electrons are expected to be rapid trapped by Mo2C nanoparticles, which contributes to the effective separation of photoinduced hole-electron pairs. As a result, the optimized Z scheme system exhibits impressive visible-light photocatalytic performance. Especially, the 2 wt% Mo2C/TCN photocatalysts exhibits superior photocatalytic performance for tetracycline degradation with a reaction rate of 0.0391 min(-1), which is 3-times and 9-times higher than those of TCN and pristine g-C3N4, respectively. The outstanding performance strongly depends on the synergistic effects among the favorable electrical conductivity of Mo2C and the multitude of charge transfer channels provided by the Z-scheme heterojunction. This work provides a new idea of designing direct Z-scheme material and it sheds novel insight to establish photocatalytic model for environmental amendment.