Photo-decomposition of organic contaminants on TiO₂ nanotube surface observed by MIR-IRAS measurement

Abstract

Despite the exceptional photocatalytic effect of TiO₂ nanotubes, the photocatalytic reaction process on TiO₂ nanotube surface has seldom been studied. In this work, by directly fabricating ordered TiO₂ nanotube arrays on Si prism, we have investigated photocatalytic reaction on TiO₂ nanotube surface using infrared absorption spectroscopy in the multiple-reflection geometry (MIR-IRAS). The in-situ observation results revealed that the O₂ is more effective than H₂O in promoting the photocatalytic decomposition of organic materials using TiO₂ nanotubes. By comparing the reaction photodecomposition of organic materials on TiO₂ nanotubes with that on TiO₂ nanoparticles, we demonstrated that TiO₂ nanotubes are superior in photocatalytic reactivity to nanoparticles.