Ferroelectric polarization synergism boosting CdS/PbTiO3 S-scheme heterostructures for efficiently bifunctional environmental applications

It is of great significance and challenges to construct physical field-enhanced photocatalysts for energy and environmental applications. Herein, an artificial-photosynthesized CdS/PbTiO3 S-scheme heterostructures with the enhancement of polarization electric field have been developed to promote the bifunctionally catalytic efficiencies for Cr(VI) photoreduction degradation of heavy metal pollution and Tetracycline (TC) photooxidation degradation of antibiotic. In our work, CdS nanoparticles are selectively grown on the positive polarization planes of PbTiO3 microplates to form the same direction for both the ferroelectric polarization field of PbTiO3 and the built-in electric field of S-scheme heterojunction. In this case, the stable heterostructures of PTO(00−1)/CdS(010) are obtained, and the greatly improved photocatalytic performances of redox degradation are achieved. The charge transfer mechanism and the synergetic effect between the spontaneous ferroelectric polarization and S-scheme heterojunction have been revealed by DFT calculations and experimental verifications. This interesting finding provides new insight into the design of efficient artificial-photosynthesized photocatalytic systems and we hope our work could serve as a valuable reference for our colleagues.