ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Visible light photoelectrocatalytic degradation of rhodamine B using a dye-sensitised TiO₂ electrode

Sayekti Wahyuningsih, Candra Purnawan, Puspa Ayu Kartikasari, and Novita Praistia

Inorganic Materials Research Group, Chemistry Department, Faculty of Mathematics and Natural Science, Sebelas Maret University, Ir. Sutami Street 36A, Kentingan Surakarta, 57126, Central Jawa, Indonesia

E-mail: sayektiw@gmail.com

Abstract: Titanium dioxide is a promising catalyst for application in the photodegradation of organic pollutants in water due to its powerful oxidising property and long-term photostability. This study presents the production of titanium dioxide using the sol-gel process, dye sensitisation of the TiO₂ electrode, and the performance of that cell. Sensitisation of titanium dioxide was performed using a dye, i.e., Fe(II)-polypyridyl complexes. The photoelectrocatalytic degradation of rhodamine B (RB) using ITO/TiO₂/dye as electrode was investigated via a series of potentials, from +1.0 V to −1.0 V, and at various pH and NaCl concentration values (ITO is indium tin oxide conductive glass). The photoelectrocatalytic degradation of RB was performed with a visible light lamp. The change in the absorbance of RB with various potentials indicated that the absorbance of RB in solution systems with the sensitised TiO₂ electrodes decreased with increasing anodic potential bias. The degradation cell exhibited better performance when the positive anodic bias was applied. The pH values of RB in solution systems also influence the photoelectrodegradation process because of the different RB species present. NaCl concentration also affects the activity of RB photoelectrocatalytic degradation due to changes in the ionic strength character of the electrolyte.

Keywords: sensitisation – photoelectrocatalytic degradation – excitation – rhodamine B

Full paper is available at www.springerlink.com.

DOI: 10.2478/s11696-013-0476-8

Chemical Papers 68 (9) 1248–1256 (2014)