0D/2D Co3O4/TiO2 Z-Scheme heterojunction for boosted photocatalytic degradation and mechanism investigation

• Published in: Applied catalysis. B, Environmental Environmental, 2020-12, Vol.278, p.119298, Article 119298
• Main Authors: Wang, Yuting, Zhu, Chengzhang, Zuo, Gancheng, Guo, Yang, Xiao, Wei, Dai, Yuxuan, Kong, Jijie, Xu, Xiaoming, Zhou, Yuxuan, Xie, Aming, Sun, Cheng, Xian, Qiming
• Format: Article
• Language: English
• Subjects: Antibiotics; Carrier recombination; Charge transfer; Co3O4nanodots; Cobalt oxides; Current carriers; Electric fields; Energy bands; Enrofloxacin; Environmental degradation; Heterojunctions; Holes (electron deficiencies); Photocatalysis; Photocatalysts; Photocatalytic degradation; Photodegradation; Recombination; TiO2nanosheets; Titanium dioxide; Z-scheme heterojunction
• ISSN: 0926-3373; 1873-3883
• DOI: 10.1016/j.apcatb.2020.119298

[Display omitted] •A 0D/2D Co3O4/TiO2 Z-scheme heterojunction was synthesized and proved.•The optimal nanohybrid could photodegrade 95.6 % enrofloxacin within 100 min.•The built-in electric field and the matched energy band cause Z-scheme system.•Z-scheme system could hinder electron-hole recombination and boost charge transfer.•Degradation pathway was deduced from Gaussian calculation and GC–MS analysis. The development of stable, efficient photocatalyst for environmental antibiotics degradation is great significant and remains a major challenge. Herein, zero dimensional Co3O4 nanodots are grown in situ onto two dimensional TiO2 nanosheets, successfully producing a Z-scheme heterojunction Co3O4/TiO2 photocatalyst for the photocatalytic degradation of enrofloxacin. The synthesized nanohybrid exhibits superior photodegradation performance (0.0269 min−1 for enrofloxacin) and excellent stability (four cycles). The matched energy bands allow the formation of the Z-scheme heterojunction, and the built-in electric field provides the reaction driving force. The formed Z-scheme heterojunction can simultaneously inhibit photoinduced electron-hole recombination, boost photoinduced charge carrier transfer, and produce more active electrons and holes, therefore generating more active species for eventual photocatalytic degradation. In addition, a the possible enrofloxacin degradation pathway was proposed based on simulated calculations and GCMS analysis. This work can inspire further design and construction of Z-scheme heterojunction photocatalysts.