Photocatalytic nitrogen fixation by g-C3N4/MoS2/PbTiO3 with synergistic electric field

Abstract

Photocatalytic nitrogen fixation under mild conditions is considered to be one of the interesting and challenging approaches to relieve energy scarcity. In this work, g-C3N4/MoS2/PbTiO3 composites are successfully designed and synthesized for photocatalytic nitrogen fixation. The interfacial electric field of S-scheme heterojunction, the polarization electric field inside PbTiO3, and the bound electric field induced by the polarized electric field synergistically construct the synergistic electric field in g-C3N4/MoS2/PbTiO3 under ultrasonic vibration. Under the effect of synergistic electric field, honeycomb structure, and nitrogen defects, the yield of photocatalytic nitrogen fixation by g-C3N4/MoS2/PbTiO3 reaches 6288 μmol·L−1·g−1·h−1, which is 6.58, 3.61, and 2.37 times that of PbTiO3, MoS2, and g-C3N4, respectively. The synergistic electric field offers a sufficient driving force for photogenerated carrier separation and migration. And the honeycomb structure and nitrogen defects provide sufficient reaction sites for photocatalytic nitrogen fixation. This work offers some insights for developing efficient ferroelectric-based photocatalysts.