Degradation of Methylene Blue and Rhodamine B Using a New Visible Light-Responsive Photocatalyst, KSb2PO8-xNy

Potassium phosphatoantimonates, KSbPO(KSbPO) and KSbPON(KSbPON), are prepared by solidstate method. Urea is employed as a source of nitrogen for N-doping. Structural, morphological and optical properties of both KSbPO and KSb PON are characterized by powder X-ray diffraction(PXRD), scanning electron microscopy, energydispersive spectroscopy, Fourier transform infrared spectroscopy and UV–visible diffuse reflectance spectroscopy. Both samples are found to crystallize in a monoclinic lattice with Cc space group. The d-lines of KSb PO and KSbPON are refined by least square fitting the PXRD data, using POWD software to obtain their unit cell parameters. The bandgap energy(Eg) of both pristine and N-doped KSbPO is found from their Kubelka–Munk plot. The KSb PON/visible photocatalytic degradation of methylene blue and rhodamine B has been investigated in aqueous heterogeneous suspension. The generation of OH in the presence of KSb PON during the photoreaction is verified by a fluorescence technique using terephthalic acid(TA) as a probe.