A green approach for degradation of organic pollutants using rare earth metal doped bismuth oxide

Much effort has done for the development of novel semiconductor photocatalyst with enhanced visible light photocatalytic activity. Bismuth based oxide have attracted significant attention in the field of photocatalysis due to its narrow band gap hence, harvest more visible light. Therefore, a strategy for the design of efficient heterogeneous semiconductor photocatalyst is propose. In this connection, we have synthesized the modified bismuth trioxide using sol gel method with excellent photocatalytic activity for degradation of three different organic dyes. The fabricated samples were characterized by using standard analytical techniques, such as XRD, SEM, TEM, BET, PL and UV–vis/DRS spectroscopy. All doped-Bi2O3 photocatalysts exhibit higher photodegradation of dyes as compared to pure Bi2O3 under visible light illumination, while the highest efficiency was found at 3.0% La doped Bi2O3 and 1.2 g L−1 dose. The enhanced photocatalytic activity of modified Bi2O3 photocatalyst can be ascribed predominantly due to their improved visible light absorption property and efficient charge separation. The photodegradation of dyes follow pseudo first-order kinetic in the presence of synthesized materials. Furthermore, the fabricated rod can be reused with little loss in photocatalytic efficiency. The results of scavengers study suggest that holes, hydroxyl and superoxide radicals play a significant role for photodegradation of dyes. The modified bismuth based oxide approach will open new avenues for the development of efficient photocatalyst for environmental remediation and energy conversion.