Insight into the Photocatalytical Activity of TiO2 Nanoparticles Through the Electrochemical Characterization of Carbon Paste Electrodes

• Published in: Electrocatalysis Vol. 6; no. 1; pp. 92 - 101
• Main Authors: Soares, Gabriela Byzynski, Vaz, Carlos M. P., Ribeiro, Caue, Hermans, Ive
• Format: Journal Article
• Language: English
• Published: Boston Springer US 01.01.2015
• Subjects: Catalysis; Chemistry; Chemistry and Materials Science; Electrochemistry; Energy Systems; Physical Chemistry; Photoelectrocatalysis; nanoparticles; TiO; Carbon paste solid electrode
• ISSN: 1868-2529; 1868-5994
• DOI: 10.1007/s12678-014-0223-0

We propose a methodology to study the behavior of semiconductor nanoparticles—especially TiO 2 nanoparticles—in photoactivated processes via electrochemical studies, using solid electrodes instead of thin-film electrodes. This strategy allows the comparison of properties probed from freestanding nanoparticles with the results of electrochemical characterization, without grain growth or texturization effects, frequently observed in thin-film electrodes. In this study, solid electrodes prepared with homogenized carbon paste and TiO 2 were characterized. The TiO 2 /carbon paste electrode showed lower currents than the carbon paste electrode under UVC illumination. The electrode containing 15 % TiO 2 /carbon paste showed better results for electroanalytical characterization. However, for electrolysis, the carbon paste electrode with 60 % TiO 2 was used, as 15 to 45 % ( w / w ) TiO 2 content was deemed insufficient for this purpose. In order to compare the electrochemical characterization with photocatalytical properties, the degradation of rhodamine B (Rhod-B) dye was used. The reaction order for the Rhod-B degradation was between first and second order, which suggests that the products of the reaction may interfere with the decomposition itself. The results will enhance the establishment of a valuable characterization route to support future research regarding the influence of different materials in photodegradation processes.