Hydrothermal synthesis of novel 1-aminoperylene diimide/TiO₂/MoS₂ composite with enhanced photocatalytic activity.

ABSTRACT: 1-aminoperylene diimide/TiO₂/MoS₂ composite (NH₂-PDI/TiO₂/MoS₂) with ordered structure was prepared by hydrothermal synthesis method. The composite was characterized by XRD, SEM, FTIR, XPS, BET, DRS, PL, EIS, Raman, photocurrent, and Mott-Schottky plots spectroscopy. The potential positions of the conduction and valence bands, and the band gap energy of the semiconductors were estimated. The composite exhibited higher photocatalytic activity compared with the mono-component systems. The apparent rate constants (k) were determined as 0.00616, 0.00352, 0.00738, 0.00517, 0.00752, and 0.00806 min^-1 for TiO₂, NH₂-PDI, NH₂-PDI/TiO₂, MoS₂, MoS₂/TiO₂, and NH₂-PDI/TiO₂/MoS₂, respectively. The detection of radical scavengers confirmed that superoxide radicals, photogenerated holes, and photogenerated electrons were the main active substances for MB degradation. Between type II- heterojunction mechanism and Z-scheme mechanism, the latter could explain the enhanced photocatalytic activity of the composite better. The Z-scheme mechanism accumulates more electrons at CB level of NH₂-PDI and hence generates more super oxide radicals.

SUBMITTER: Ma Y 

PROVIDER: S-EPMC7738548 | biostudies-literature | 2020 Dec

REPOSITORIES: biostudies-literature