Synthesis and characterization of nanostructured Cr doped TiO2 materials for photocatalytic applications

• Main Author: Tan, Dunlin
• Other Authors: Tan Ooi Kiang
• Format: Theses and Dissertations
• Language: English
• Published: 2009
• Subjects: DRNTU::Engineering::Electrical and electronic engineering::Electronic apparatus and materials
• Online Access: https://hdl.handle.net/10356/14969
• Institution: Nanyang Technological University

Titanium Dioxide for applications as a photocatalyst has received much attention since its water splitting capability was discovered in 1972. However, the efficiency was a big drawback due to its large bandgap of 3.2 eV. Since 1990s, minded researchers have been focusing on shifting its bandgap into the visible light range so as to increase its efficiency. The various techniques utilized are not complex and cost effective. Visible light activity was not observed and efficiency remains low. Hence, its novelty through cheaper alternatives of synthesis suitable for commercialization proved to be very appealing. In this project, Chromium and Chromium Oxide doped titanium dioxide synthesized by high energy ball milling technique are studied. The high energy ball milling technique is cheap and is a solid state top-down method where breaking and making of new bonds can lead to the synthesis of novel materials suitable for photocatalysis applications. Their physical and optical characteristics were studies. A test of its photocatalytic reactivity was also investigated. The powders were then fabricated into composite films, using the modified sol-gel technique, for ease of application testing. In this method, the synthesized powders are distributed and incorporated into a film, whose conditions is symbolic to a coating on a wall. Similarly, their optical and physical properties were discussed.