Ag/Fe 3 O 4 /WO 3 − x nanocomposite photocatalysts, which consist of surface plasmon nanoparticle Ag, magnetically recoverable Fe 3 O 4 , and coral-like WO 3 − x , are constructed via two-step hydrothermal and photodeposition processes. The significantly strengthened photothermal catalytic-Fenton degradation performance under light irradiation is attributed to the formation of a hierarchical structure, as follows: (i) the unique 3D coral-like defective WO 3 − x nanorods possess the inherent properties of charge separation and can provide adequate surface active sites, while incident light is reflected multiple times within the nanorods to enhance light utilization; (ii) efficient photo-Fenton characteristics of Fe 3 O 4 nanomaterials with easy magnetic recovery and fast electron transfer emerging at the intimate interface of Fe 3 O 4 and WO 3 − x ; and (iii) the surface plasmon resonance (SPR) of Ag nanoparticles and photothermal effects. Radical scavenger experiments and electron spin resonance analysis indicated that •OH and •O 2 − are the main active species for the removal of broad-spectrum pharmaceuticals and personal care products. Furthermore, a possible photothermal catalytic-Fenton synergistic mechanism is proposed. This study will present novel deep insights into the design of photothermal catalytic-Fenton degradation systems using magnetically Fe 3 O 4 coupled WO 3 − x semiconductors and the SPR effect.

No abstract

Rational design of composite nanostructured photocatalytic systems with good sunlight absorption capacity and efficient charge separation and transfer ability is an urgent problem to be solved in photocatalysis research. Here, a ZnMn2O4 decorated three-dimensional carbon nitride with O, C co-doping, and nitrogen defect composite photocatalytic system was prepared using a simple hydrothermal method and subsequent calcination method. For the photocatalytic reactions, the presence of heterostructures, C, O co-doping, and nitrogen defects greatly promotes the separation and transfer of charges at the semiconductor/semiconductor interface under the local electric field, thereby extending its service life. The photocatalytic degradation efficiency of sulfamethoxazole in water is as high as 94.3% under the synergistic effects, which is also suitable for the complex water environment. In addition, the synthesized photocatalyst has good chemical stability and recyclability. This study provides a new opportunity to solve the problem of environmental pollution.

No abstract