Microwave Solvothermal Synthesis of Three-Dimensional Bi2MoO6 Microspheres with Enhanced Photocatalytic Activity

Constructing a Titanium Silicon Molecular Sieve-Based Z-Scheme Heterojunction with Enhanced Photocatalytic Activity

Titanium silicon molecular sieve (TS-1) is an oxidation catalyst that possesses a long lifetime of charge transfer excited state, high Ti utilization efficiency, large specific surface area, and good adsorption property; therefore, TS-1 acts as a Ti-based photocatalyst candidate. In this work, TS-1 coupled Bi2MoO6 (TS-1/BMO) photocatalysts were fabricated via a facile hydrothermal route. Interestingly, the optimized TS-1/BMO-1.0 catalyst exhibited a decent photodegradation property toward tetracycline hydrochloride (85.49% in 120 min) under the irradiation of full spectrum light, which were 4.38 and 1.76 times compared to TS-1 and BMO, respectively. The enhanced photodegradation property of the TS-1/BMO-1.0 catalyst could be attributed to the reinforced light-harvesting capacity of the photocatalyst, high charge mobility, and suitable band structure for tetracycline hydrochloride degradation. In addition, the mechanism of photocatalytic degradation of tetracycline hydrochloride by the TS-1/BMO-1.0 catalyst was reasonably proposed based on the band structure, trapping, and ESR tests. This research provided feasible ideas for the design and construction of high-efficiency photocatalysts for contaminant degradation.

Accelerated radical generation from visible light driven peroxymonosulfate activation by Bi2MoO6/doped gCN S-scheme heterojunction towards Amoxicillin mineralization: Elucidation of the degradation mechanism

A novel S-scheme photocatalyst Bi₂MoO₆ @doped gCN (BMO@CN) was prepared through a facile microwave (MW) assisted hydrothermal process and further employed to degrade Amoxicillin (AMOX), by peroxymonosulfate (PMS) activation with visible light (Vis) irradiation. The reduction in electronic work functions of the primary components and strong PMS dissociation generate abundant electron/hole (e^-/h⁺) pairs and SO₄^*-,*OH,O₂^*-reactive species, inducing remarkable degeneration capacity. Optimized doping of Bi₂MoO₆ on doped gCN (upto 10 wt%) generates excellent heterojunction interface with facile charge delocalization and e^-/h⁺ separation, as a combined effect of induced polarization, layered hierarchical structure oriented visible light harvesting and formation of S-scheme configuration. The synergistic action of 0.25 g/L BMO(10)@CN and 1.75 g/L PMS dosage can degrade 99.9% of AMOX in less than 30 min of Vis irradiation, with a rate constant (k_obs) of 0.176 min^-1. The mechanism of charge transfer, heterojunction formation and the AMOX degradation pathway was thoroughly demonstrated. The catalyst/PMS pair showed a remarkable capacity to remediate AMOX-contaminated real-water matrix. The catalyst removed 90.1% of AMOX after five regeneration cycles. Overall, the focus of this study is on the synthesis, illustration and applicability of n-n type S-scheme heterojunction photocatalyst to the photodegradation and mineralization of typical emerging pollutants in the water matrix.