The visible light-driven photocatalytic degradation of Alizarin red S using Bi-doped TiO2 nanoparticles

• Main Authors: Sood, Swati, Mehta, Surinder Kumar, Umar, Ahmad, Kansal, Sushil Kumar
• Format: Article
• Language: English
• ISSN: 1144-0546; 1369-9261
• DOI: 10.1039/c4nj00179f

In this paper we report the preparation of a series of Bi 3+ -doped TiO 2 nanoparticles with different Bi-concentrations, i.e. 0.25-5% by a facile sol-gel process and their application as an efficient photocatalyst. The detailed characterization revealed that the Bi-doped TiO 2 catalysts possess densely grown nanoparticles, a high specific surface area, crystalline anatase TiO 2 and good optical properties. The incorporation of Bi 3+ into the TiO 2 lattice led to the expansion of the TiO 2 spectral response into the visible light region and the efficient separation of charge carriers. The prepared samples were employed for the photocatalytic degradation of Alizarin red S dye (ARS) under visible light illumination. It was found that the incorporation of the Bi 3+ ions in the TiO 2 lattice causes a marked improvement in the photocatalytic degradation of the ARS dye; however, the degradation efficiency depended upon the Bi +3 ion doping concentration and the dose of the prepared catalyst. The detailed photocatalytic experiments confirmed that the 1% Bi +3 ion doping concentration and 0.1 g L −1 dose exhibited the best photocatalytic degradation efficiencies for the model dye. Moreover, more than 80% degradation of ARS was observed by the prepared Bi-doped catalysts within 90 minutes under visible light. The synthesized Bi-doped TiO 2 nanoparticles revealed a superior photocatalytic behavior towards the photocatalytic degradation of ARS under similar experimental conditions, as compared to the synthesized TiO 2 nanoparticles and other commercially available derivatives (TiO 2 PC-50 and TiO 2 P25). Ultrasonic assisted sol-gel synthesized Bi-doped TiO 2 mesoporous nanoparticles with a good crystallinity and high surface area were prepared. The 1% Bi-doped TiO 2 catalyst showed the highest photocatalytic activity under visible light.