Photo-induced degradation of norfloxacin by nanosilver modified two-dimensional black phosphorus

The construction of highly efficient photo-induced degradation methods is essential for water remediation. A novel nanocomposite was firstly synthesized, which was consisted of Ag nanoparticles immobilized on black phosphorus nanosheets (AgNPs@BP). The structure, surface area and morphological properties of AgNPs@BP composite were broadly investigated by atomic force microscopy (AFM), transmission electron microscopy (TEM), scanning electron microscopy (SEM) and X-ray diffraction (XRD). The factors which is crucial to the degradation efficiency of norfloxacin including light conditions, pH value, catalyst type, reaction temperature, catalyst dosage and initial norfloxacin concentration, were investigated. The photocatalytic performance of the designed samples was investigated based on the photo-induced degradation of norfloxacin under near infrared light irradiation. The results confirmed that under the optimal conditions, about 85.0% of norfloxacin was rapid degraded within 90 min. In addition, this AgNPs@BP can be easily reused for 5 cycles without significantly reducing catalytic activity. Generally, a photocatalytic mechanism is proposed based on monitoring of center dot O-2(-) in the reaction. The enhanced photocatalytic activity of AgNPs@BP nanocomposite was ascribed to the sensitization of BP nanosheets by fully harvest of near infrared light and high electron-hole separation efficiency. This work broadens the applications of BP and highlights its promise in the treatment of environmental pollution.