Mesoporous titania accommodated with In2O3 nanoparticles as a superior photocatalyst for degradation ciprofloxacin antibiotic

Abstract

• Sol-gel process was utilized for synthesizing a novel In 2 O 3 /TiO 2 photocatalyts. • Ciprofloxacin (CIP) was utilized to estimate the photocatalytic performance. • The optimum 1.5% In 2 O 3 /TiO 2 indicated the highest efficiency ∼100% within 60 min. • The mechanism of the In 2 O 3 /TiO 2 photocatalyst was proposed according to S-scheme. • In 2 O 3 /TiO 2 photocatalyst exhibited high stability for five consecutives cycles. Antibiotics are emanating pollutants due to their wide consumption and production, which causes hazards to human health and the ecological environment. Herein, the sol-gel process was utilized for synthesizing novel mesoporous In 2 O 3 /TiO 2 photocatalysts employing a soft template. The photocatalytic ability of the In 2 O 3 /TiO 2 nanocomposites was assessed through ciprofloxacin (CIP) degradation over visible light exposure. It could be found that 1.5% In 2 O 3 /TiO 2 nanocomposite exhibited the highest CIP degradation rate compared with bare TiO 2 nanoparticles (NPs). The 1.5% In 2 O 3 /TiO 2 nanocomposites indicated strengthening the photocatalytic performance ∼100% within 120 min to degrade CIP compared with the bare TiO 2 NPs (10%) because of the construction of heterojunctions, which could be reinforced the separation efficiency of photoinduced electrons-holes. The apparent rate constant of 1.5% In 2 O 3 /TiO 2 photocatalyst was determined to be about 0.013 min −1 , 13 folds larger than bare TiO 2 NPs (0.001 min −1 ). The photocatalytic ability was kept after recycling five times without depletion. The fostered photocatalytic ability was referred to as the transport of photoinduced electrons-holes between In 2 O 3 and TiO 2 , verified by photocurrent response and photoluminescence measurement. The photocatalytic reactions of the In 2 O 3 /TiO 2 photocatalyst were proposed according to the S-scheme mechanism. This work provides a favourable way to construct heterojunction photocatalysts for practical application in the destruction of organic contaminants.