Articles
  • Synthesis of Bi2W2O9 from an amorphous complex precursor: characterization and evaluation of its photocatalytical properties
  • A. Martínez-de la Cruza,*, S. Obregón Alfaroa, Leticia M. Torres-Martínezb, I. Juárez Ramírezb
  • a Facultad de Ingeniería Mecánica y Eléctrica, Universidad Autónoma de Nuevo León, Ciudad Universitaria, C.P. 66451, San Nicolás de los Garza, N.L., MEXICO b Departamento de Ecomateriales y Energía, Universidad Autónoma de Nuevo León, Ciudad Universitaria, C.P. 66451, San Nicolás de los Garza, N.L., MEXICO
Abstract
Bismuth tungstate Bi2W2O9 has been synthesized using diethylenetriaminepentaacetic acid (H5DTPA), an organic chelating agent of metals in an aqueous solution. The formation of the oxide was followed through characterization techniques such as XRD, TGA/DTA, and SEM. The optimum temperature to decompose the organic matrix and to form Bi2W2O9 was determined to be around 720 oC. Below this temperature, Bi2W2O9 was formed with a high content of Bi2WO6. At 720 oC particles of the Bi2W2O9 with a surface area four times higher than that obtained by a solid-state reaction were obtained. The oxide was tested as a photocatalyst on the degradation of aqueous solutions of rhodamine B under VIS radiation. The photodegradation of the dye followed a kinetic first order with an apparent constant, k = 2.8 × 10−3 minute−1and t1/2= 247 minutes for an aqueous solution of 5 mg l−1 of rhodamine B.

Keywords: Bismuth tungstate, Bi2W2O9, Photocatalysis, Rhodamine B.

This Article

  • 2008; 9(5): 490-494

    Published on Oct 31, 2008