Ag-single atoms modified S_(1.66)-N_(1.91)/TiO_(2-x)for photocatalytic activation of peroxymonosulfate for bisphenol A degradation

In this study,Ag_(0.23)/(S_(1.66)-N_(1.91)/TiO_(2-x))single-atom photocatalyst was synthesized by in-situ photoreducing of silver on S,N-TiO_(2-x) nanocomposite and used to degrade bisphenol A(BPA)through heterogeneous activation of potassium peroxymonosulfate(PMS)under visible-light illumination.The structure,physicochemical property,morphology,and electronic property were evalutated by X-ray diffraction(XRD),Raman spectrum,X-ray photoelectron spectra(XPS),high-resolution transmission electron microscopy(HR-TEM),UV-vis diffuse reflectance spectra(UV-vis DRS),electron paramagnetic resonance(EPR)spectrum.Ag_(0.23)/(S_(1.66)-N_(1.91)/TiO_(2-x))single-atom photocatalyst exhibited 2.4 times higher activity for the synergetic degradation of BPA than that of its counterpart,and 48.73%mineralization rate of BPA also achieved.It was ascribed to the uniformly-dispersed metallic Ag atoms as the active site for accelerating the migration rate of photo-generated carrier for generation of high reactive radicals.The EPR experiments indicated that SO_(4)^(-) and ^(·)OH was jointly involved in BPA degradation.