Preparation, characterization and photocatalytic activity studies of transition metal ion doped K2Ta2O6

Cation doping is one of the simplest methods to improve the photocatalytic activity. Herein, we attempted to improve the photocatalytic activity of K2Ta2O6, by doping with M2+ (M = Mn, Co and Ni) ions. The M2+-doped K2Ta2O6 were synthesized by facile ion-exchange method and characterized by techniques like XRD, SEM-EDS, TEM-SAED, N-2 adsorption-desorption, FT-IR, XPS, UV-Vis DRS and PL. The photocatalytic activity of these catalysts was studied for the degradation of methylene blue (MB) dye under visible light irradiation. All the M2+-doped KTO exhibited improved photocatalytic activity towards the degradation of MB. Among these catalysts, Mn-K2Ta2O6 has shown 93% degradation efficiency in 180 min of irradiation. Scavenger experiments were performed to unravel the degradation mechanism. The stability of Mn-K2Ta2O6 and its photocatalysis mechanism were also presented.